tag:blogger.com,1999:blog-15443822383173980052024-02-19T02:15:25.306-06:00DX AdventuresThe life and times of a world traveler who seldom actually leaves home! DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.comBlogger82125tag:blogger.com,1999:blog-1544382238317398005.post-49860215165922923262021-03-17T21:06:00.001-05:002021-03-17T21:06:31.569-05:00What Is a Typical Weekend on the Radio for the DX Adventurer<p> What does the average DX-er do when he or she sits down at the radio? Some may have a plan, a specific program from a specific station they want to hear. There may be a plan to scan a particular band and look for new stations not heard before. There may be desire to log a new country or listen on a band of frequencies not normally tuned at that time of day to see if something unusual is going on. It might be to look for a station posted by a fellow member in a Facebook listening group to see if it makes it to your location or to help the other poster identify something he or she is hearing. There might be a radio contest on the ham bands that might be used to log new countries or just log as much DX as you can in the target rich environment.</p><p>Or it just might be no plan at all. It might just be that you sit down at the radio, turn it on, and just pick a spot at random and start tuning to see what happens. I must tell you, that for me, more than half the time, that is exactly what happens. There are currently seven working radios at my main operating position that can be powered up and switched to an antenna at a moment's notice. Sometimes the time of day will have me picking a radio that performs best for the bands that are open that time of the day or night. Sometimes it just might be that for one reason or another, one particular radio has been used almost exclusively for awhile and there is a desire to try something different. Or maybe one particular radio just hasn't been used in awhile and there is a desire to " blow the dust out."</p><p>That is pretty much what happened back last September 18. I realized I had been leaning on the Yaesu FT-950 almost exclusively with the Hallicrafters SX-71 sitting right next to it going virtually unnoticed. The Yaesu can be a spectacular radio for pulling out DX especially in the ham bands and on cw. I had picked up the SX-71 mostly for casual listening to shortwave broadcast stations and for medium wave DX. That one evening I was just thinking about seeing what I might be able to dig out on the ham bands on cw. So without much other thought, I switched it on and moved the antenna input lead from it to one of the positions on my antenna switch. ( I have coaxial pigtails running from the inputs of all my receivers up to the area of an antenna switch, which obeying the laws of nature, results in more inputs than positions on the switch. I also have the capabilities or running any antenna either directly to a radio or through either an antenna tuner or an active preselector) Some of the radios run off AC power via a heavy duty power strip behind the desk and the 12 volt radios and other 12 volt accessories all run from a single 30-amp Astron analog supply. No switching supplies to generate noise in this shack!!</p><p>Anyway, the evening of September 18, 2020 Texas time, or 0000 GMT, the lights behind the dual slide rule dials of the SX-71 lit up and the aircraft headphones used here plugged in, the S-meter swung up to the right, then down to about S-2 with the ambient noise on the W6LVP Loop that was the antenna selected at that moment and the noise came up in the headphones as they settled over my ears.</p><p>Now where to start? The past few nights I had been tuning through 40-meter cw using the FT-950, so the thought was, " let's see what the SX-71 will do in comparison."</p><p>There was no way to accurately set the bandspread band edges at the time...no crystal calibrator so the band entries were simply " 7 mHz" instead of the four-digit entries plus two decimal points usually written down for stations tuned in on the '950.</p><p>There was a few minutes for the receiver to settle down, before the pitch of the tuned in signals stopped sliding down as the radio drifted during warmup. I figured enough time would just about equal the time needed to grab a fresh cup of real ( no de-caf here!) coffee and sit back down. Starting at the big cluster of FT8 signals and tuning down frequency WA3CKA was heard...then just down frequency a super strong signal totally blew past the BFO reminding me that on these radios, one must ride the RF gain or sensitivity control back to prevent this from happening with strong signals. K4EJU was really barreling in. Turning off the BFO, the Smeter showed S-9 plus 20 db. ( on some of these radios the AGC goes off when the BFO goes on) Tuning down further with the selectivity in the narrowest position and the BFO pitch control set off to one side of the pass band, more stations came up from behind the strong ones " out front". A much weaker signal was heard and with careful tuning it became readable, though it was up and down in level more than the others. Turned out to be NN7CW/M . A mobile cw station! This brought back memories of my days on the road doing broadcast engineering work and running various rigs cw mobile---the best being an SBE-33 and Icom 701, but that whole thing is a story for another day.</p><p>OK, so this part of the band was mostly for folks rag chewing. To find some DX, lets go down to the bottom of the band. The bandspread was just turned down frequency until I totally ran out of stations. Since I did not have a good accurate band edge marker at the time, that was the best way I could think to get to the edge...just tune down until there weren't any stations and slowly creep back up until I ran into some. Tune slowly, carefully, turn the rf gain back up and listen carefully. Maybe one would show up. Yep, there one is, working North Americans with them giving their locations just as their states without naming cities ( always a clue they are working DX) After a few minutes of listening, the signal crept up enough to identify. It was ON5EJ from Belgium. There would be DX.</p><p>From there, lets tune up and see if we can find some more. Next station up was stronger, but also closer identifying as VE3DXG, not real DX but a good ways from Texas. Going up the band I found several stateside stations that were identified and put into the log ( I log EVERYTHING) WX8J, W6P ( special event station for something?) W0A, K2HYD, K5DX, KA1CDD, another Canadian VA3SZ, then a Cuban CO7JY very strong.</p><p>For the next hour it was like that, going up the band logging each station identified, sort of like some folks do when running a band sweep on medium wave. All pretty routine until I ran into a bit of a pile up. Whoa, might be something good at the bottom of the pile. After about ten minutes of listening including the usual frustration when guys trying to work him not getting the rhythm right and calling on top of him, the signal peeped out into the open enough to identify ( I was reminded of a cartoon seen in an old QST or maybe CQ magazine once many years ago that had a drawing of a receiver dial with a big pile of cats in a swirling pile of dust with a little mouse labeled " DX" tip toeing out of the edge of the teeming mass....why do I remember these things? Funny how a mind drifts when doing these things) Oh yes, you are wondering what the station was ( drum roll....) ZS1JX South Africa!!! A jewel found in the big hay pile. There he was, all by himself coming across the Atlantic with very few other DX stations being heard. So strange that it happens that way. Maybe the band was just really long. It was 0150 GMT so it was almost 8 in the morning there. How WAS this happening? Reminder to self for the zillionth time since starting this hobby: why its good to listen and tune and search when the band doesn't necessarily sound all that hot or DX stations are not just hopping out of the woodwork or maybe nothing at all is listed on DX Summit.</p><p>The funny thing really was I heard the same station ZS1JX at almost the same time and almost the same frequency the next night. Who knows?</p><p>That next night, September 19 beginning at 0100 GMT once again using the SX-71, things started with VE2CSI, again mostly US stations, but a few more Europeans: HB9CVQ from Switzrland ( a real regular on 40 meter cw) DD7CW from Germany, I1YRL from Italy, the aforementioned ZS1JX, CO8OH Cuba, OP5KD Belgium with lots of US stations interspersed. Two pages in the spiral notebook filled up and sleep creeping up by 0300 GMT, I did my usual OCD thing and filled out a page to the bottom, reached up and turned the radio off. </p><p>Some nights are better than others, with the big ones often being the ones written about. But this might give you a snapshot of just an ordinary day " walking around the world" in this shack. Hasn't changed much since the first tentative tuning around with a broadcast radio while looking at White's Radio Log back in 1957. What's a typical night at your place? Drop a note in " comments" If enough show up, perhaps a few of them could be gathered up together in a future blog entry.</p><p>Good DX!</p>DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-87370512996083778712021-03-14T20:00:00.001-05:002021-03-14T20:00:39.283-05:00Tuning the Ham Bands with Analog Dial Boat Anchors <p><br /></p><div style="clear: both; text-align: left;">For those relatively new to the hobby, the ability to read frequency out to three or four decimal places is a given. Digital readout is the norm and for many almost a necessity for normal day to day listening. Obtaining a boat anchor receiver or one with an analog dial might bring what might be a daunting task. For the relatively new ham used to digital readout, things might be particularly daunting. </div><div style="clear: both; text-align: left;"><br /></div><div style="clear: both; text-align: left;">For many of us old timers, the age of digital readout has been a real gift, making easy what used to be a difficult thing, knowing exactly where we are. There were methods of doing that, though they may be a little misty in memory. For today's SWL the ability to go to a specific frequency at a specific time might not be considered a luxury. Identifying a station now is a matter of going to a website and entering a frequency and being told what stations are on the air at that moment and what language, power, and beam heading they are using. For those tuning the ham bands, websites like DX-Summit can tell you what DX stations are on the air at that very moment and what frequency they are on, allowing the astute listener to go to that frequency and camp out, waiting for the prop to bring them home. ( of course for some for whom this has brought the closest thing to instant gratification the hobby can deliver, if the station is not heard right away, its on to something else or " the conditions are rotten I'll go watch television")</div><div style="clear: both; text-align: left;"><br /></div><div style="clear: both; text-align: left;">For those of us who grew up in the hobby without such luxuries, or who are rediscovering the old radios and the fun they can be, some of these techniques will need to be relearned or recalled.</div><div style="clear: both; text-align: left;"><br /></div><div style="clear: both; text-align: left;">For most boat anchors, there were two tuning dials which made at least tuning the ham bands a bit easier and provided a good way to know at least generally where we were. For some, even with an analog dial, one could get a pretty good approximation within 5 khz or so of the frequency in use...sometimes even better.</div><div style="clear: both; text-align: left;"><br /></div><div style="clear: both; text-align: left;">The ham band only receivers had dials directly calibrated with the frequencies of the five or six major amateur bands available at the time. The general coverage receivers had a main turning dial calibrated in general terms with a separate bandspread dial that gave a form of fine tuning with the dial face calibrated in the actual amateur bands. A small handful of radios --the National NC-190 for example--also offered calibrated band spread for the major shortwave broadcast bands as well.</div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMzIdJmGorFuuZYJGsPrM0xcnh3UQvPcsFxFyeH7sPKfERLBub3a8_cb_IHb7cmVKlwFCjq68MNilJR-yWCmMHDCoAX9JZJVHkD3oeLvx5gXpqr84JlODNLTdCk4tarhyphenhyphennMp_00-0z7ZvA/s2048/SX-71+BANDSPREAD.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="2048" data-original-width="1536" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMzIdJmGorFuuZYJGsPrM0xcnh3UQvPcsFxFyeH7sPKfERLBub3a8_cb_IHb7cmVKlwFCjq68MNilJR-yWCmMHDCoAX9JZJVHkD3oeLvx5gXpqr84JlODNLTdCk4tarhyphenhyphennMp_00-0z7ZvA/s320/SX-71+BANDSPREAD.jpg" /></a></div> Hallicrafters SX-71 bandspread dial<br /><div style="clear: both; text-align: left;"><br /></div><div style="clear: both; text-align: left;">In order for the calibration to be correct for the bandspread tuning, it is necessary for the main tuning dial to be set at a proper starting point. There would be marks on the main tuning dial that were meant to be the proper starting point. One tunes the main dial to that point, and then would tune the bandspread dial to explore the band. Of course all of this relied on the accuracy of the main tuning dial calibration and the proper alignment of the radio. Even on a new from the factory receiver this might not be 100 percent accurate. This brings into play the need to find some sort of beacon or marking spot to make sure the main tuning control is properly set. One way this can be done on some bands is to set the bandspread ahead of time to the frequency of a known station then carefully tune the main tuning until you hit that spot. In the sixties, this was really easy on forty meters at night because Radio Tirana Albania held down the 7300 khz spot with a gonzo signal.</div><div style="clear: both; text-align: left;"><br /></div><div style="clear: both; text-align: left;">A note here about forty meters. In North and South America, forty meters is allocated for amateur use from 7000-7300 kHz. In Europe and Asia, hams only get 7000-7200 with the last 100 khz being allocated for broadcast use. In the old days, European and Asian hams only had 7000-7100 meaning that the upper portion of the band was loaded with high power broadcast stations that at night made the forty meter phone band and what was then the novice cw band in North America difficult at best and almost unusable at worst. In those days Novice licensees were limited to 75 watts INPUT ( usually resulting in 50 watts or less to the antenna) and were crystal controlled. Crystals in the early sixties cost at least $1.50 apiece, an hour's pay for many at that time. If it happened that a Novice had only two or three crystals and they happened to be one of the many frequencies occupied by the flame thrower Radio Moscow transmitters of they day, it meant no operating at night.</div><div style="clear: both; text-align: left;"><br /></div><div style="clear: both; text-align: left;">The other way to set the main tuning properly as a starting place to insure proper bandspread calibration was to use what was known as a crystal calibrator. This device which was available as standard equipment in some receivers or as an option in others, put out a marker signal every 100 kHz. That meant that you could set the upper or lower band edge of the bandspread tuning on frequency, then tune the main tuning until you hit the marker signal. Then as you tuned up through the band, you could check the receiver tracking at every 100 khz point. Some receivers did not track 100 percent accurately and you would correct the main tuning setting at the closest 100 khz point. To make sure that the calibrator was properly set, you would tune the receiver to one of the WWV frequencies and turn on the calibrator, then adjusting a small trimmer adjustment to zero beat the calibrator against WWV.</div><div style="clear: both; text-align: left;"><br /></div><div style="clear: both; text-align: left;">For receivers that did not have a crystal calibrator or even the provision for one, there were kits available for external crystal calibrators. In fact, today there are still those available for purchase on the internet through Amazon or EBay that are much simpler to use than in the old days. The output of the crystal calibrator is just loosely coupled to the input of the receiver then turned on when you need a calibration point. Some calibrators also offer 25 khz markers, giving more frequent calibration points.</div><div style="clear: both; text-align: left;"><br /></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhoH0el6sm-GBMJK1mh4LLVRtURF4xarSWGJnfFdKB8yy83krSxqmY_z7QNPa2F06p_51truzzEqpHVwLlm0EyLzsVH9jZuBJlIaet_ywt_dNuhRo18MHCfk4l3fAvTiQ9clkYBD9HBeO2E/s2048/SX-96+BANDSPREAD.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="2048" data-original-width="1536" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhoH0el6sm-GBMJK1mh4LLVRtURF4xarSWGJnfFdKB8yy83krSxqmY_z7QNPa2F06p_51truzzEqpHVwLlm0EyLzsVH9jZuBJlIaet_ywt_dNuhRo18MHCfk4l3fAvTiQ9clkYBD9HBeO2E/s320/SX-96+BANDSPREAD.jpg" /></a></div> Hallicrafters SX-96 bandspread dial<div><br /></div><div>The amount of bandspread available on these older receivers varied a bit from radio to radio and from band to band, usually with wider bandspread and more frequent markings on the lower bands. In the two examples shown, the Hallicrafters SX-71 and SX-96 used in my shack, the forty meter band has markings every 20 khz. With the main tuning properly set, it is possible to easily determine and estimated frequency to within 5 khz or so. The halfway point between dial markings is 10 khz and if you can eyeball well enough, the quarter space determination can give you 5 and 15 khz readings. If you get good, you might be able to "eyeball interpolate" a little closer.</div><div><br /></div><div>Without a crystal calibrator or handy broadcast station to provide a marker, a very popular mode of operation on the bands gives a fairly good marker down in the cw portion of the bands. FT8 signals are very distinctive with the main FT8 frequency being around 75 khz up from the bottom of the band. If you are not looking for frequency meter determination, but just general logging estimations you can set the bandspread tuning to 7075 ( or 14075, 3575 etc) then tune the distinctive FT8 beehive of signals in with the main tuning dial. It won't be super precise, but will get you enough in the ballpark to know you are not looking outside the band for DX stations or not getting all the way to the bottom and miss some. ( I would NOT suggest using this method to determine if you are putting an analog dial transmitter on frequency!!!)</div><div><br /></div><div>What does one do for the shortwave broadcast bands for which these radios generally do not have calibrated bandspread? I will get to that at the same time I tell you about that category of radios that does not even have calibrated bandspread for the amateur bands. Some receivers only have bandspread calibrated 0-100 or in some cases, 50-0-50 or something similar. These are radios like the Hallicrafters S-38, S-120, and my S-118 or the National NC-60, NC-105, NC-121 or the Radio Shack DX-150 and 160.</div><div>Many of the radios that do have calibrated bandspread for the ham bands also have a 0-100 band spread for use on SWBC.</div><div><br /></div><div><br /></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1HpZdNyI9Yzg5eBvdmFDQ0g_jO1nwgOM1nR3brzfKvl-szCEaYGN_s0-peczNOcS7BVl9RUJGQXt4dZkXyQvzqdoVANh-zVno5lRUipHQpGjht-bcVP8H2rM1s3e5d23YKBOB-k5_Pdvg/s2048/s118+4.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="2048" data-original-width="1536" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1HpZdNyI9Yzg5eBvdmFDQ0g_jO1nwgOM1nR3brzfKvl-szCEaYGN_s0-peczNOcS7BVl9RUJGQXt4dZkXyQvzqdoVANh-zVno5lRUipHQpGjht-bcVP8H2rM1s3e5d23YKBOB-k5_Pdvg/s320/s118+4.jpg" /></a></div> Hallicrafters S-118 dial<br /><div><br /><div style="clear: both; text-align: left;"><br /></div><div class="separator" style="clear: both; text-align: left;">There can be no direct dial calibration with these radios, but there is a way to at least have a rough idea of where we are. Through the use of the crystal calibrator one can find the band edges at least. There is also the method of using the FT8 signals as a marker to find the cw band.</div><div class="separator" style="clear: both; text-align: left;"><br /></div><div class="separator" style="clear: both; text-align: left;">If a crystal calibrator is available, by tuning through two or three of the markers, one can note how many dial calibration marks there are between the markers, then determine that number of khz are denoted by those marks. For example, on forty meters, each mark on my S-118 dial amounts to 6 khz.</div><div class="separator" style="clear: both; text-align: left;">This may be done with the shortwave broadcast bands for the general coverage receivers that have calibrated bandspread for the hambands, but not for SWBC. It will not be as precise as digital readout but you can at least get a general idea where in the band you are. You might not be able to go directly to some online list and identify a station you are hearing, you might just have to use an old school method of identifying a station while using an old school radio...hear the ID or determine it from some other clue while listening. And you might not be able to pinpoint some ham DX station you see on DX Summit or some other spotting network, you might have to use the old school method...scanning the band and looking for it by listening through the crowd. At least the spotting networks can still tell you that it is there to be sought!</div><div class="separator" style="clear: both; text-align: left;"><br /></div><div class="separator" style="clear: both; text-align: left;">Using these old radios may not be as easy as some of the new ones, and certainly not like some of the SDR's, but some might call it more sporting...and for some of us, it brings back some of the thrill that a bit of uncertainty might bring.</div><div class="separator" style="clear: both; text-align: center;"><br /></div><div class="separator" style="clear: both; text-align: center;"><br /></div><p></p></div>DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-46824848316996338112021-03-11T21:01:00.001-06:002021-03-11T21:01:34.643-06:00Tuning a DX Contest With the Knight SpanMaster--a REAL adventure<p> After using first line receivers for DX Contests for years, it might seem strange for someone to use a very basic, simple receiver to hunt for DX in one. The idea came as I thought back to the days when I operated my first contests using a National NC-88, a single conversion radio with no filters and very broad selectivity. I remember the frustration at trying to pick signals out of the seemingly hip-deep pile of stations from one end of the dial to the other, and when some could be copied they were only the strongest stateside stations.</p><p>But those were the first couple years as a licensed ham before I knew much about the strategy of working contests and before I had developed " DX-er's Ears" or the ability to discern between different stations by pitch or developed tuning techniques that helped and the sense of rhythm that can be used to copy weak stations during the breaks in transmissions of the strong ones.</p><p>I had wanted a SpanMaster for some time. In fact it was one of the first receivers I had wanted when still just a listener. Allied Radio had three regenerative receivers that could be called " budget radios" then, the Ocean Hopper, Space Spanner and SpanMaster. As it turned out, I never got my wishes, but did end up with a National SW-54 for my first "factory built" short wave radio. I thought at the time that it was pretty good, but it was, in fact, little more than an AllAmerican Five AC/DC radio that happened to cover the short wave bands.</p><p>The idea was to see if my listening skills developed over the years would allow me to hear things I could not seem to hear then, and beyond that as a challenge. There was also the thought that hams back in the 20's and 30's used these simple receivers and were certainly hearing and working DX.</p><p>There are a few things to consider that are different in using a simple receiver and something like my R-75 or FT-950. Beyond the very obvious lesser apparent selectivity and sensitivity there is the absence of what used to be called " single signal reception." The term has not had to be used for a long time because virtually every receiver of any note made in the last fifty years ( except the consumer portables) already have it. It refers to a cw signal being heard on only one side of the zero beat as you tune across it. </p><p>In older or wider selectivity receivers, as you tune up to and past a cw signal, you hear it first at a high pitch, then as you get closer and closer to the actual frequency, the pitch goes lower and lower until it actually goes through zero, of"zero-beat". Then as you tune further onto the other side of the signal, it becomes audible again and goes to a higher and higher pitch until you get far enough away from it that its finally disappears. The tighter the selectivity, the less that distance is. What you are hearing is the beat of the signal against the Beat Frequency Oscillator, without which the unmodulated on-and-off keying of the cw carrier would not be heard, or at most would sound like a series of thumps. The pitch depends on the difference in frequency between the BFO and the desired signal as it sweeps through the IF of the radio. </p><p>In front line radios, the BFO is permanently set at one side of the passband and the narrow "doorway" for the desired signal is adjacent. The signal is audible on one side of the BFO, but as it is swept across it and out of the passband, by the time it would reach the point where you would hear it go up in pitch again, it is either attenuated to the point that it is inaudible altogether or at the very least way down in level from what it was when tuned for peak signal strength.</p><p>But in a regenerative receiver there is no IF stage. You are listening on the actual frequency. There is no filter and therefore no way to create single signal reception. The only selectivity you have is that which is created by the detector oscillating. True, in a well designed regenerative receiver this can be pretty tight, but there is no way to get the single signal effect. There are a couple of techniques in tuning that can sometimes help that situation out a bit in a crowded band, but more on that later.</p><p>The other condition that must be dealt with is the fact that a regenerative receiver must actually be in oscillation for the cw signals to be heard. There is no Beat Frequency Oscillator. The radio is actually oscillating on-frequency with that signal beating against the incoming signal. If a signal is weak, this is not a problem, but if a signal is strong, it might overpower the internal oscillation, requiring the amount of feedback or regeneration to be increased. In some designs, this might cause a shift in frequency. And the incoming signal itself might "pull" the detector off-frequency.</p><p>You can see that with all of this going on, tuning of one of these little jewels to copy a weak signal next to a much stronger one can become bit of an art, or perhaps better described as a juggling act.</p><p>Then there is plain old drift. These radios are not the most stable of things under the best of conditions. You might be listening to a signal, waiting for an ID or to copy other information, and notice the pitch slowly, slowly ( or sometimes not so slowly) shifting up or down. One does not take one's hand off the tuning knob of these things. And the other hand might need to be on the regeneration control. What does this leave you with to write callsigns on a scratch pad or even put them in the log? Its best to be able to copy in your head and just remember the information until you can let go and write it in the log. Sometimes one hand might be free for a few seconds to write the callsign and other info directly in the log. This might explain why log entries made using these things are not quite as pretty as they might otherwise be!!</p><p>So, again, why do this? Well, it is a challenge, it is a throwback to younger days during which one can be transported back to see " what might have been" in those days.</p><p>( As an aside, some of the stability problems and lack of single signal reception along with overload were some of the same problems I had to deal with in using the old National SW-54!)</p><p>All of these conditions might seem enough to deal with in trying to copy cw with this receiver on the best of days with good band conditions and not much crowding.But then add in the wall-to-wall signal situation you find with a DX contest and mix in the gonzo signals or the big gun DX contest stations running full legal power into huge beams, and this might seem like total insanity!</p><p>After playing with the radio for a few days, I decided that the best band to try would be forty meters. There would be a very good chance of good DX signals plus the radio was more stable there than on twenty meters. Also the antenna to be used was my 44 foot vertical which is pretty good on forty meters where a quarter wave is 33 feet, but not so good on 80 meters, where the stability of the radio might be better but the antenna is a bit short ( quarter wave on 80 meters is 66 feet and at least a quarter wave is needed to give the lower angle response needed for real DX) The vertical is made of pieced together scrap aluminum, but RF doesn't care about that. And the vertical does set on a field of 60 radials, so the little rig will be given a fighting chance.</p><p>So here it was, Friday afternoon, nearing 0000 GMT, contest starting time. The SpanMaster had been warming up for an hour, I had might light early supper and snacks and "Ham Radio Dad" coffee cup strategically placed around the desk. My usual preparations for tuning through a DX test were all in place, extra note pads, lots of extra pens, but of course a work-related phone call came just before start up time. But by 0020 that little crisis had been dealt with and my aviation headset was on my head and tuning began.</p><p>Whoa! There were a lot of signals on the band! It was not dark here in Central Texas yet so I was not sure how soon I might find some DX, so I logged a few domestic stations since I was receiving only.</p><p>KU8E and K3ZO were boiling in and fell into the category of those needing to have extra regeneration to copy. At 0030 I heard a weak station and could tell in his report to stations worked he was not giving a state, but something else. This told me that he was a DX station because US and Canadian stations give signal report and state in this contest and all others give signal report and their power.</p><p>It was going to be difficult to copy him through the heavy stateside qrm, but I used one of the tricks I had learned years ago. The strong interfering station was above him in frequency, so I tuned down through zero beat and onto the other side of him, accenting the difference in pitch. That helped some, but there were portions of this transmissions that were still being blocked. However, by listening through several contacts, his callsign and information became readable when they landed at a time when the interfering station was listening rather than transmitting. This became a bit of the norm during this whole adventure and resulted in sometimes two or three minutes needed to get all the information. So much for logging two a minute as was usual with the R-75 or FT-950!</p><p>Finally at 0030 GMT, I copied his callsign: EA3F Spain! There was hope this would not be a waste of time!</p><p>Even at that the DX did not flood into the log. It was four minutes later before I identified my next "target" and it was a Canadian, VA2UR at 0034. Five minutes later I copied NP2K in the Virgin Islands, it was six minutes later that I pulled out PJ2T Curacao, but then only two minutes later NP4DX followed by NP4Z, both Puerto Rico.</p><p>( Another aside here: Has anyone else noticed that sometimes two stations in the same country will be almost on top of each other? I have noticed this several times over the years. In this case, both Puerto Rican stations were audible at the same dial setting and simply separated by the difference in pitch method)</p><p>One more Caribbean station was logged before another European call made it. ZF1A in the Caymans was super strong, up there with the big gun stateside stations.</p><p>It was a tough several minutes after that, but at 0113 another station from Spain, EA4W, was logged.<br />Then three minutes later CR6X from Portugal ( don't get overwhelmed by this high logging rate now!!)</p><p>It was eight minutes after that when LZ9W from Bulgaria was pulled out.</p><p>And that was kind of how it went into the evening...sometimes three or four minutes between loggings, sometimes more.</p><p>A sample with times followed by callsigns and locations: 0137 OK4Z Czech Republic; 0143 IR2C Italy; 0154 KP4AA ; 0155 EA2W Spain; 0157 IR2Q Italy; 0200 II9P Italy.</p><p>Just when it seemed like things were going better there was a gap of fifteen minutes spent trying to identify a weak station that kept getting clobbered. I could hear the reports he was giving and he was listing his power as a kw, but everytime he gave his callsign, another station picked that time to call "CQ TEST": Finally he got a break and gave his call in the clear: 4O4T Montgenegro.</p><p>I could see this was going to be a pull. Almost as a gift, the next one pulled out was only two minutes later: S51YI Slovenia.</p><p>It went on like that, sometimes a minute or two, sometimes as much as 20 minutes before a station could be pulled out. There were a few that I felt noteworthy for some reason: 0244 LU7HY Argentina; 0257 YL7TX Latvia; 0312 IT9ESW Sicily; 0326 KL7RA Alaska; 0327 9A9A Croatia; 0338 EA8RM Canary Islands; 0352 CT1GFK Portgugal.</p><p>There were of course, others in between. Like I said, not setting the world on fire in the great scheme of things but satisfying in its own way to log them with a little two-tube radio.</p><p>I shut down at 0400 with the plan to get up the next morning to see if any Asians could be heard.</p><p>I started the next morning Texas time at 1130 GMT and the start was once again slow: 1149 NP4G Puerto Rico; 1147 P44W Aruba; 1150 CO6RD Cuba. What was this? Was I only going to hear Caribbean stations after getting up early?</p><p>Things changed drastically after that. I spent nine minutes trying to pull out the callsign of a station that was listing power as 200 watts. Over and over his call slipped by me...but it turned out to be a really good one: FK8IK New Caledonia! That would have been good on any radio!</p><p>Minutes later at 1201 GMY an old friend KH6LC from Hawaii showed up. Two minutes after that JE1NHD should up listing a kw; at 1212 GMT a very satisfying ( though also very familiar) ZM1A New Zealand. Then a ten minute gap before another old friend, JH8YOH Japan showed up. Then what I thought would be the prize of the morning at 1228 GMT, VK2IA Australia. </p><p>It was beginning to seem like it had been worth the effort. The sun was coming up, and I knew there might not be much time left, but there was time to get JK2GRX, JH4UYB, JA6JCE and JH4JNG in the log. </p><p>There was another good one to be had at 1306 GMT with the sun up as ZM4T came in. But to show you the rule about waiting one more bit before shutting down really paid off with the " oh wow" of the morning at 1312 GMT when YB8RW Indonesia came in.</p><p>I shouldn't have been too surprised, because Indonesia always comes in on forty meters a bit after sunrise, but I really did not expect it on the SpanMaster.</p><p>I shut it down after that, very pleased with the results. Of course nothing like the usual two to three a minute that can be pulled in with the R-75 with two back to back 250Hz filters or the FT-950 tightened down all the way. But very pleasing all the same.</p><p>It raised questions about my early days, however. How did I miss all this stuff with the NC-88 which even such that it was should still have stood shoulders above the SpanMaster? I guess the answer is in skills learning to copy through QRM through the years or something. My horizontal antennas back then were not very high, but I did have a vertical then too ( though it was a Mosley V-4-6 trap) Who knows?</p><p>But whatever it was, this was a great adventure of its own and won't be the last time I hunt for DX with the SpanMaster. </p><p>There have also been other nights that I have spent time listening with the Hallicrafters SX-71 and SX-96 which both do very well on cw DX...and also the somewhat simpler Hallicrafters S-118. For some reason using them has brought back some of the real electric excitement to the hobby....almost like back in the days when an 11-year-old boy went running through the house yelling, " Hey Daddy, hey Mom, come look what I heard!!!" </p><p>Its a great hobby. And I never know what might show up when I tell my wife as my old late friend Earl Sterling used to say, " I think I'm going for a short walk around the world."</p>DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-65120165675393337902021-03-09T17:48:00.000-06:002021-03-09T17:48:07.288-06:00DX-ing With the Knight SpanMaster<p> </p><p>Its pretty easy to get comfortable with the equipment one is using over time, and often just as easy to wonder if there is something better than what you have, something that will make it easier to find and hear the DX.</p><p>Then when you get the radio that seems to do it all, slice and dice signals only 200 Hz apart, dig signals out of hip deep noise, read out frequency to ten Hz, let you spot a desired station on a data base or spotting network and allow you to tune right to it and just wait for the prop to put it in your lap, why would you want to go back to something with almost none of those capabilities?</p><p>Over the past several years, I have been very fortunate to have a series of excellent receivers, some of which can do all of the above.</p><p>In years past I had one of the premier receivers of the 1960's, the Drake 2B. For a time I had a Collins 75S-3. In recent times up through today I have been using an Icom R-75 with dual 250 Hz Inrad filters and a Yaesu FT-950, with a Yaesu FT-757-GX in reserve. I have had some boat anchors that I used for casual listening but one day when looking back at logs from my very beginning time as a DX-er, I got to wondering if perhaps some of the DX I missed was due to the gear I had or just from my not knowing how to listen as well. </p><p>This triggered using a couple of the older receivers to listen during a couple ham contests and found I could hear some of the DX with them. It only made sense, I mean hams that had that gear when it was new certainly heard and worked DX without digital readout and DSP.</p><p>And that brought back thoughts of those early receivers and what I might have done with them today. That brought memories of pouring over the old Allied Radio catalogs that I started sending off for in 1957, and of staring at pictures of a trio of Knight Kit regenerative receivers: The Ocean Hopper, the Space Spanner and the SpanMaster. I wanted one of them very badly at the time, but it never came to be. As time went on, I began my listening with my grandfathers's old Watterson 5-tube broadcast radio, then a homebrew receiver and eventually with a National SW-54 and beginning my ham career with a National NC-88.</p><p>For some reason, my thoughts centered on the SpanMaster, perhaps because a school friend had one back in the early 1960's when I already had my National. I wondered just what I might have heard with it, if there could have been DX with it.</p><p>Thus began a search for one, looking on E-Bay and other places. Two friends assisted in the search and some months later my friend Drew found one. It arrived in fairly good shape, but had a terrible AC hum and no stations were audible through it. Thus came the next step of ordering capacitors and replacing all of them, not just the electrolytics, but all of the paper caps. My friend John, whose eyes are better and hands are steadier than mine in my old age, took care of the rehabbing and even replaced the old selenium rectifier with a solid state diode.</p><p>Soon it was ready to come to its new home.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEikHNPBtugjLjyCDyBdksN_1PTt5crKG8CVk_cguXTfoh85COku3i3250Dvgruk_6juuPQrZ_bPMAM_xhOXvrom0mEwmeTT823C0gNI4tD9V1Pp84W5mcK-hwSC12TkyO5Elohr4M-oQX31/s2048/SPANMASTER.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="2048" data-original-width="1536" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEikHNPBtugjLjyCDyBdksN_1PTt5crKG8CVk_cguXTfoh85COku3i3250Dvgruk_6juuPQrZ_bPMAM_xhOXvrom0mEwmeTT823C0gNI4tD9V1Pp84W5mcK-hwSC12TkyO5Elohr4M-oQX31/s320/SPANMASTER.jpg" /></a></div><br /><p>I had already been playing with the boat anchors a bit more, relearning some of the techniques for tuning for DX with broader selectivity, analog dials and listening for callsigns in a jumble. </p><p>February 1, 2021 at 0100 GMT I fired it up after making a place for it on the desk on a shelf above the FT-950. The antenna used was my home built 44 foot vertical over a radial field fed with RG8-X. I had no idea how the calibration of the main tuning dial might be, so I set the bandspread at full counterclockwise, with the bandspread capacitor fully unmeshed and planned to hunt for a WWV signal and try to figure out where I was. </p><p>Tuning a regenerative receiver truly is an art. As the noise came up in my headphones, I inched the regen control up and heard the "plop" of oscillation starting and began tuning on Band "C", looking for the 5 mHz WWV. I could not believe it! It popped right up, amazingly close to the 5 Mhz spot! Playing with the regen control and tuning carefully up the band, Radio Rebelde from Cuba on 5025 came in very well. Inching up the dial carefully, its band mates also showed up: Radio Havana on 5040 and the rock and roll of WTWW on 5085. This was going well so far. There was a bit of time playing with the regen, finding the " sweet spot" for AM and the best selectivity.</p><p>A trip down to Band "A" and a tune through the broadcast band gave more practice in adjusting the regeneration and tuning. XEG from Monterrey on 1050 was good and easily separated from WHO in DesMoines on 1040. Dial calibration was pretty close. A quick spin down the dial over the next hour resulted in the "usual suspects" easily being logged: Radio Encyclopedia 530 from Cuba, XEWA on 540 from San Luis Potosi, XEX on 730, KTRH on 740, WSB on 750, WBAP on 820, WWL on 870, XEW on 900, XEQ on 940, local KBBW on 1010 gave a little practice on dealing with a strong signal and a reminder of how they will "pull" a regen receiver and require more regen. The rest of the hour was spent playing with the dial and the knobs and relearning how to tune the regen. Then it was enough for the night.</p><p>The next night it was time to try some CW on the ham bands. Since it appeared that Band "C" was pretty close to on calibration, I decided to try forty meters first. With the bandspread set all the way over, I began tuning the main tuning down to the edge of the forty meter mark on the main dial and pretty close to it started running into ssb signals. It was pretty near on!</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjHmWeDU5_kiX3eqUmhsukr1Yii2KLEpxYbizIMyk0sI8D8iiPVW9mZ6rvWVV1_iw8UI45S2r20_4geK-vGO9qZpLaGo1Y4bCsCmh42amH3gjTG9tRX18xw1iQczonp7osRneEji4c6rZ-w/s2048/IMG_3830.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="2048" data-original-width="1536" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjHmWeDU5_kiX3eqUmhsukr1Yii2KLEpxYbizIMyk0sI8D8iiPVW9mZ6rvWVV1_iw8UI45S2r20_4geK-vGO9qZpLaGo1Y4bCsCmh42amH3gjTG9tRX18xw1iQczonp7osRneEji4c6rZ-w/s320/IMG_3830.jpg" /></a></div><br /><p>Tuning down past all the ssb signals with the bandspread, I kept going until I ran into the characteristic FT8 signal cluster getting me down into the cw band.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJ08oLdRS_SiR9UsGORGKGrPNmtZJ4MNuwzVYAZYLQHBmu0ryA3vHAx4hb7pQuy0AW6U7NFtzInF0I17ir6hasWU0pwdJXU5cxii7V7rBRncLCFG09tcK1RNHJ8JwQlkUTM4CUcZ9Qeb6a/s2048/Spanmaster+Bandsread.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="2048" data-original-width="1536" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJ08oLdRS_SiR9UsGORGKGrPNmtZJ4MNuwzVYAZYLQHBmu0ryA3vHAx4hb7pQuy0AW6U7NFtzInF0I17ir6hasWU0pwdJXU5cxii7V7rBRncLCFG09tcK1RNHJ8JwQlkUTM4CUcZ9Qeb6a/s320/Spanmaster+Bandsread.jpg" /></a></div><br /><p>Tuning carefully further down, I ran in to some CW signals and quickly identified my first two:N0ENV and W4AG. It took a little fiddling around with tuning and the regeneration controls to find the sweet spot for cw, copying K4NAX and K4ZNC. Signals were a little drifty and tended to be a bit chirpy when strong as the receiver was pulled, but copyable. But would there be any DX?</p><p>That question was answered just a few minutes later as I heard stations working a fellow and just giving signal report and state and clearing. It took a bit of fiddling with the fine regeneration control and very touchy tuning, but soon identified HK5NLJ/3 from Colombia. My first ham DX on the little two-tube regen. In a few minutes that callsign was joined by XE2I and VA3SZ in the log. Before sleep overtook me, I had a half page of callsigns written into the log.</p><p>The next few nights were spent polishing the tuning technique. Many stateside stations were logged. I was back in my childhood listening mode, logging and writing down every station identified, regardless of DX or not. </p><p>The next milestone came February 5 with listening starting at 0030 GMT, a good start with VE3KZ first in the log on forty meters. Almost a full page of callsigns came next, but the real break came at 0213 when the first cross-the-ocean DX was logged with I1MMR.</p><p>We were on the way. The radio worked, DX could be heard and I was advancing on the learning curve.We might just be ready for a real test in a couple of weekends when it would be time to try it out in a real DX contest. But that's a story for another day!</p><p><br /></p>DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-68574527879712596992021-03-08T18:32:00.000-06:002021-03-08T18:32:47.410-06:00The Annual Coastal DX Trip<p> For the last several years, my family has made a vacation trip to the Texas gulf coast. At first we stayed at motels on Galveston Island. Then one year we shared a rented beach house house on the Bolivar Peninsula with our daughter, son-in-law, and grandkids in the small community of Crystal Beach, a short ferry ride from Galveston.</p><p>On previous trips when we stayed in motels I would take my Radio Shack DX-440 or a Sony portable and do a little casual listening on a motel room balcony or occasionally sitting in a chair on the beach, Seldom were any antennas actually erected except one year when I stood up a twenty meter quarter wave vertical at the water's edge. (you can find that story along with pictures in the archives of this blog Scroll down and look for "Mini Beach DX Trip" in 2015)</p><p>However for real DX with a decent antenna, nothing beats a beach house with a direct, unobstructed view of the salt water of the Gulf of Mexico. From Bolivar Peninsula, there is access to an over-water path from almost due east through south and around to southwest. That first beach house vacation changed everything, leading to that being the location of choice. Of course it was not the same one every year. Some years the house would be on the front row, nearest the water. Others it might be on the second or even third row, depending on how much lead time we had before going, what was available and what our budget was for a given year.</p><p>This year the trip had to be rescheduled twice because of hurricanes.</p><p>This year our rented house was not on the front row, but there was not a house on the lot in front of it so there was actually the advantage of having more room to string an elevated wire sloper. Plans for a long beverage did not work out because of the presence of a road about 300 feet from the house between it and the beach.</p><p>After unloading all the family luggage, with the help of my grandson the installation of the antennas began. The W6LVP loop went up on a couple sections of fiberglass pipe on the upper deck balcony, placing it almost 30 feet above the ground. Another stack of poles held the upper end of the wire that was then strung out across the back yard and the vacant area between the house and the water. The upper end was up about 35 feet and it sloped down to the ground with a length of somewhat over 250 feet, sloping toward the east southeast. The length was not measured, it was just tied off at the upper end and stretched out until we ran out of room.</p><p>The R-75 was set up on a table in the top floor sitting room and there was immediate disaster. There was horrible noise across all bands, though interestingly enough, it was only S-6 on the MW band. It was the same on the loop as on the wire. It could not be nulled with the loop. We tried moving the loop ot into the yard away from the house and it was a little better. I had only brought 75 feet of coax so we could not get that much farther away.</p><p>So what does one do in such circumstances? One plows ahead as best one can, beginning in the area where the noise was least and the environment was target rich: MW,</p><p>The initial run on September 29, 2020 was just a short run before dinner at 0220 GMT checking for a few Cubans. This was just about sundown and the regular for Texas listeners on 530 khz was booming in: Radio Encyclopedia at well over S-9 with none of the R-75 preamps turned on. Transmitters for Radio Reloj were heard on 570 and 850.</p><p>The next afternoon about an hour and a half was spent on a MW groundwave band scan using the loop. Starting at the bottom of the band, a 1 kw station from a Dallas suburb made it on 540 khz. All of the Houston area stations were quite strong, topped by 50 kw KTRH on 740 that was full scale on the R75 Smeter, again with no preamps on. There were a few surprises, including a station from Reynosa, Mexico on 590 that pushed through 5 kw KLBJ from Austin, I am sure aided by a straight path over water.</p><p>The real demonstration of the signal assistance of a water path was the reception of Radio Rebelde from Cuba on 670 khz at three o'clock in the afternoon local time.</p><p>Since the noise was lower on the sloping wire than on any orientation of the loop, it was used, with a note to self to bring more coax next time in case this problem should come up again.</p><p>During the daylight groundwave sweep some of the highlights were Reynosa, Mexico on 810 at S-6; XECT 1190 Monterrey, Mexico S-7 (!); XEEW 1420 Matamoros S-6; KRZI 1660 Waco, Tx S-6; KRJO 1680 Monroe, La S-6; KZLS 1640 Enid, Oklahoma S-5 ; KWKH Shreveport, La S-5;KDLF 540 Ferris, Tx ( near Dallas 1 kw) S-6!</p><p>The water path to New Orleans was excellant with the mid afternoon signal from WWL on 870 booming in at well over S-9.</p><p>But overall, the results were disappointing because of the high noise level. The usual daylight signals I had heard in years past from the Yucatan were just not audible . </p><p>The trip was not exclusively a radio trip, as these never really are. There were grandchildren and daughters present and things to do besides radio. Time in the surf, birds to be watched, sea food to be eaten and other things that have little to do with electrons zipping through wires. These things must always be kept in perspective.</p><p>Every trip will not be a blazing success. In this case, the last night in the beach house gave a bit of an answer. The grandkids went home and we were to leave the next morning. For the first time since we were in the house, both televisions were off. And the noise was gone.</p><p>Unfortunately packing to leave the next morning had already begun and there was little time for last minute DX-ing.</p><p>There will be other trips and other times and perhaps more radio time on another trip. Something is always learned on any trip and this lesson was trips are not always successful.</p><p>There was one final listening adventure. A quick sweep was made through the 60-meter band before the R-75 was packed up. A mystery was noted that others would be musing over for months. There was a very strong signal on 4940. It was in Spanish and appeared to be religious and was not identifying. There was a Peruvian listed on the frequency in the WRTH but showed to only be 1 kw and I had never logged it before at home or on previous trips. Others were to report it in the weeks to come and eventually months later it would be determined to be a reincarnation of a station in Colombia. I heard it at home several times over the next months myself, often about S-5 or so, sometimes down in the grass. However that night at the beach just before the R-75 was turned off for the last time on the trip, it was a solid S-9 plus 10 db.</p><p>Oh well, there will be other trips and other times.</p><p>Such is the world of DX.</p><p><br /></p><p><br /></p><p><br /></p><p><br /></p>DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-91605142793946092892020-05-18T19:53:00.000-05:002020-05-18T20:11:43.176-05:00Can real DX Be Heard on a Regenerative Receiver<br />
<br />
In an earlier episode, I told about the somewhat unplanned project to build a regenerative receiver.<br />
It was done out of a desire to see how such a radio would have performed if I had had one when I was a young kid.<br />
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The project had a regenerative detector and two stages of audio and included bandspread tuning and was expected to tune about 6-18 mhz.<br />
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The first night it was finished, I tuned through the dial just to make sure it was working and to get some idea what frequency range it actually tuned.<br />
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It ended up being a couple of days before I was able to get back to the little radio, with things coming up at work and household projects that had to be taken care of.<br />
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The first test run had shown that the radio worked and a couple maritime cw stations along with a broadcast station or two and time signal station WWV were heard.<br />
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A couple days later, I sat down in front of the rig with it actually set up on the desk as it would be used, rather than turned on its side with test leads connected and tools and such scattered all over the place.<br />
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The first step taken was to get a better idea of what was where on the dial, which was only calibrated 0-100. I had already found where 10 MHz was because of WWV and where 9420 was from finding the very well known Greek broadcast station. It was decided to use my ham transceiver to get a few more calibration points.<br />
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I put my Icom 720 on a dummy load and had the drive turned all the way down to provide the test signals. Then calibration points were found for the bottom and top of the 40, 30 and 20 meter ham bands. Tuning up from the mark for the top of 20 meters had me running into the 15 MHz WWV which gave another calibration point.<br />
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Going down the other way, the radio did not tune down far enough to reach the 5 MHz WWV. In fact, the bottom of the 40 meter band just did make it within the tuning range of the radio, and the 49 meter shortwave broadcast band didn't quite make it at all at first. By turning the tuning slug all the way in on the input coil, only a portion of it could be reached.<br />
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I spent a little time getting the feel of the controls tuning through the 20 meter cw band. It seemed that the most stable point for copying cw without overloading the radio was with the regeneration control set just barely past the point of oscillation.<br />
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It being early summer, twenty meters was still open with lots of signals even at just before sundown.<br />
It was obvious that the selectivity was not going to be as good as the Icom or my FT-101 with its 200 Hz cw filter. It might prove difficult to pull out weak signals from DX stations in a crowd.<br />
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But then, it must be possible, because in the early days of hamming, regenerative receivers were all many ops had....and they did work DX. But were the bands as crowded as today? No way to know.<br />
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So it was down to tuning. Starting high in the cw portion of the band, I immediately ran across a strong station that could only be one thing from the content....it was an ARRL bulletin. It seemed somewhat appropriate that one of the first ham stations in the log from the little receiver would be the ARRL Club Station, W1AW !!!<br />
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Going on down the band netted a number of US stations, but there was still hope for some DX. The little rig did not disappoint. It took some very careful juggling of regeneration and bandspread controls, but soon I had confirmed an ID for OA4CWA from Peru!<br />
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I was pretty happy with that, but there would be a few more. Within the next half hour I had logged OM3KFF from the Slovak Republic, IK3HZK from Italy and F1MCC from France. Not rare DX by any stretch of the imagination in the eyes of big time DX-ers, but I felt it was pretty good for the little regen rig.<br />
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A quick run down to 40 meters did not yield quite as spectacular results. Stateside signals were much stronger and it was early in the evening. I did identify K4DMT, W0RFN and KA9KWR. I was anxious to try a run through the maritime cw band at 8 MHz, but did stop on one last station that could be considered DX I suppose, KP4/W8HNI from Puerto Rico.<br />
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The maritime cw band was a real bit of an adventure, but in some ways was a little easier, first from the standpoint that the stations generally ran more power than hams, and also because they were not piled on top of each other helter skelter and were easier to separate. In about 45 minutes I was able to put several of them in the log. Those pulled out included the following:<br />
PJC Netherlands Antilles<br />
FLBA ( being a four letter call apparently a ship as opposed to a shore station)<br />
NMC<br />
WNU Slidell, Louisiana<br />
FUF Guadalupe Island<br />
WNU-33 Slidell<br />
WCC Chatham, Mass. ( probably the best known of the shore stations of the day)<br />
ZSC Capetown, South Africa<br />
VCS Halifax<br />
FFL St Lys Radio, France<br />
DAN Norddeich Radio, Germany<br />
OST4 Ostend Radio, Belgium<br />
HPP Panama<br />
CLA Cuba<br />
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Not bad stuff for a junk box regen radio.<br />
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( And another good reason for keeping logs. Then and now I log virtually everything I hear each time I hear it and have kept logs going back to 1957)<br />
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Over the next few days, I played around with some things trying to overcome the overload and pulling that occurred with some stations. I ended up putting a 100 pF variable capacitor in series with the hot lead of the antenna to provide a little decoupling at times.<br />
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It may seem perhaps sacrilege but at one point I brought out a little MFJ tuned preselector and put in front of the input. It was not so much as to provide gain for weak signals, as there was really no need for that. It did seem to provide a little " cushion " between the antenna and the detector and let it see a more stable load on the grid circuit. Most of the time the gain control on the preamp was kept very low. The additional selectivity did seem to help.<br />
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It is unfortunate that other things got in the way of spending much more time on the little rig. Field Day was coming up and a local group was planning to operate at a nearby park and attention got diverted from it.<br />
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After Field Day, pieces for a 10-meter beam were picked up and the design and construction of the yagi got my attention, working out the details of maximum gain, optimum wide spacing of the elements, then getting it on top of the 40 feet of Rohn 45G that had grown outside the shack at my folks house ( my dad, who is now a silent key and I had a joint shack for a time when I lived in an apartment and before I moved to my current location across town with my own real yard and future antenna farm)<br />
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After that it was more projects, overtime at work, and other things and the little radio got put on the shelf. Now almost thirty years later, it sits dust covered in my back yard shop. Perhaps its time to dust it off, re cap the power supply and bring it into the indoor shack and give it a chance to pull in some more DX.<br />
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Thinking about it still brings back the says of yearning for a Knight Ocean Hopper or Span Master. It would be nice to find one and spend some time twirling the dials, but unfortunately they are not great in number any more and the collectors seem to snap them up and put them on a shelf, not leaving many to be found by us old geezers who would just like to spend some time with them finding adventure.DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-65780392330562255182020-05-16T13:59:00.002-05:002020-05-16T13:59:57.551-05:00A Trip Back in Time<br />
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I think we may have all done this at one time or another. We've sat in front of our quasi-modern rig and thought back to days before we had such nice gear, wondering if knowing what we know no we could have landed more DX with older, simpler gear than we have now.<br />
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There is also the desire perhaps to have a chance to get the receiver or transmitter that we wanted then. It might not be a matter of thinking the gear would be better than what we have now, as much as a curiosity of finding out if it was as good as we thought it might be.<br />
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From experience at picking up some of these rigs at hamfests, I have come to learn that sometimes this is true and sometimes not. The gear might be better than we had " back then" but sometimes we learn that perhaps it was more a matter of learning how to use radios better that has lead to more DX.<br />
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I have often longed for one of the old Knight regenerative receivers that I wanted so bad as a kid. I never got one and ended up with what was probably a better receiver for a first SWL rig anyway ( a kit from a radio-tv correspondence course my dad had taken) That radio was not without its own frustrations, including very broad selectivity, almost no image rejection, and a level of stability that almost required keeping a hand on the tuning knob while listening to a station for more than five minutes.<br />
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But the urge to find out just what might have been struck rather hard one day in the early nineties as I set in my quasi-modern ( i.e. less than twenty year old) rig during a stormy afternoon. The static was so bad that listening was like having a little man inside my headphones delivering blows from a little sledge hammer directly onto my eardrums.<br />
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Thoughts turned toward a construction project, perhaps a regenerative receiver knowing what I know now and seeing if any real DX could be heard with it.<br />
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At the time I had a pretty well equipped junk box ( ok, more like a junk closet) full of various parts, transformers, salvaged chassis and other goodies, along with a huge stock of tubes, I began the search. I already knew what I would start with. I had picked up a chassis and front panel that had been somebody's home brew project for something at a hamfest. It had a two-gang variable capacitor of the broadcast type along with a small transformer power supply. It looked like it might have been some kind of signal generator. The capacitor had a gear reduction drive on it and there were three octal tube sockets behind the panel and some other holes, along with a really nice panel light.<br />
The dial on the front was calibrated 0-100, not unlike what my first SWL receiver had had.<br />
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The first step was to strip out everything including the wiring for the power supply. I already had plans for that which included building a choke input filter that would give somewhat less than the 180 volts that came out of it as it stood, but would also give a little bit better voltage regulation.<br />
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The it was decided that I would use a 6SN7 for the detector. This tube is a dual triode and I figured that I could at least have an audio stage to give a bit more audio to the headphones.<br />
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The junk box yielded a collection of Miller factory made coils that I had bought in a closeout at a local electronics store that was closing up. There were coils for the broadcast band, 1.6 to 6 MHz and 6 to 18 MHz designed to be used as input coils tuned by a 365 picofarad variable capacitor. Since I had had a broadcast band regen set as a kid, I decided I wanted short wave, and a range that would give at least a chance at hearing some DX. So the 6-18 MHz coil was chosen.<br />
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The only thing was, the coil had just two windings: a coupling coil meant to go to the antenna and ground, and a slug tuned main winding meant to go to the input of the first stage. There needed to be a tickler coil for feedback for regeneration. I took care of that by winding a few turns of enamel covered magnet wire from the junk box.<br />
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I was beginning to get into the deal by this point, so rather than just scramble winding it over the other windings and taping it down, I actually used a little shellac to hold it permanently in place. There just happened to be a nice 3/8's inch hole right next to the octal socket nearest the variable on the chassis that would make a good home for the coil, with the active windings somewhat shielded from hand capacity effects under the chassis.<br />
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While the shellac was drying, I got to work on the power supply. It was pretty quick. I pulled a 5Y3 out of the tube stash figuring it would have plenty of current capability for what this little thing would pull. There were both 6.3 and 5 volt filament windings on the transformer along with the tapped high voltage secondary. Both filament winders were center tapped, so this was going to work out nicely. I had a filter choke salvaged from a scrapped out Silvertone radio that went in place and one of the extra holes in the chassis allowed a for-real can-type filter capacitor to be used, a dual section 30 microfarad job.<br />
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Noticing a nice hole the right size for another tube socket was right next to the filter cap hole, I got to thinking that while I was part-way to having a nice, stable power supply, why not go whole hog and regulate it....so a VR 150 went into the spot. The project was quickly taking on a life of its own. I figured I would send the regulated voltage to the half of the 6SN7 used for the detector and let the other half run off the unregulated part of the supply.<br />
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That left one other tube socket empty over near the right rear part of the chassis. By now the project had grown from an quick afternoon throw-together thing to a four day after work thing. How about another audio stage so this monster could drive a speaker instead of just headphones. A quick dig in the tube stock turned up a 6V6 and a plate-to-voice coil transformer that just barely fit on the chassis. ( ok so I cheated a bit, the mounting tab on one side of the transformer was too close to the edge and it would be held in place by just one screw...don't tell anybody)<br />
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All of this set me to wiring up the audio part first. A quick trip to the RCA Receiving Tube Manual front section led to information on resistance coupling audio stages to match up the second half of the 6SN7 to the grid of the 6V6. There would not be room for another audio transformer so this would be necessary. <br />
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An aside here, the RCA and Sylvania tube manuals are excellent sources of design information and info on theory of tube circuits. They are becoming rare so snagging one at a ham fest is a good idea if you do anything much in the line of building tube-based projects or repairing boat anchors. RCA printed two versions, one for receiving tubes and one for transmitting tubes. Even without building anything, they make fascinating reads and there is a ton of true geek material to look through regarding the characteristics of the tubes. I used these as study material for my ham licenses and for getting ready for the test for First Class Radiotelephone License ( no mere GROL--the real thing) back in the sixties.<br />
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There were four holes in the lower front of the chassis and panel that I was using, so a potentiometer for a volume control went into the right-most hole. I did not use the AC power switch on the back of the pot because I wanted to keep the AC voltage well away from the detector wiring, knowing from experience that regenerative circuits can sometimes be susceptible to hum anyway. This led to one rather unorthodox thing...the power switch was a toggle switch mounted on the left side of the chassis near the rear next to a fuse holder.<br />
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Those were the only holes I had to drill in the chassis and kind of went against the original idea of using things as they were. I really did not want to build an unfused power supply ( NEVER be tempted to do this!!) and did not want to use one of those in-the-power-cord things.<br />
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Wiring up the audio stages went pretty quickly. The volume control was put in the grid circuit of the second half of the 6SN7. That stage was then resistance coupled to the input of the 6V6 stage. <br />
Another trip to the tube manual helped determine the value of a cathode resister for the 6V6 for self bias with a bypass capacitor across it to ground.<br />
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Just like in the old magazine construction project articles, it was decided to test the audio stages before the detector was wired up, mainly so if things didn't work there would only be one place at a time to trouble shoot. The power supply was already tested and had about 170 volts unregulated and a nice 150 volts regulated. A six volt bulb was put in the little pilot light socket already in the panel and the smoke test begun.<br />
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No problems. The whole thing was almost too simple for anything to go wrong, but you never know... There was only a very faint hiss and no hum ( yay!) coming from the speaker with the volume control all the way up ( grid of the 6SN7 highest above ground) A little finger touch to the center lug of the volume control brought a satisfying growl from the speaker so it appeared all was well.<br />
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Time to get to the meat of the project. I had decided that even with the gear reduction drive on the main tuning capacitor, it might be nice to have a little bandspread tuning. A small variable with only three rotor plates taken from some old rig that had been junked for parts was used. It went in one of the lower front panel holes. <br />
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That left the question of regeneration control. I had decided against using resistance controlling so as not to give too much of a changing load to the plate of the detector while making adjustments to the feedback. The plan was to have the ticker feedback winding high side go to the plate of the detector through a 100 picofarad capacitor ( plate voltage on the cap through the winding not a good idea with<br />
fingers near it)with the " cold end of the winding going to the stator places of the small capacitor that would control the feedback. Since the rotor side of most variables is common to the frame, that side was going to ground. The shaft of the capacitor was cut short and an insulated coupling and extension used to go to the knob to try to reduce hand capacity effects.<br />
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From there, it was just running the mica capacitor paralleled with a resistor from the grid of the 6SN7 half used for the detector to the top end of the tuning coil, and the other side of the coil to ground. The coupling winding went through a short piece of shielded audio cable to a chassis mount SO-239 fitting on the back right side of the chassis.<br />
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Then there was a capacitor to couple the plate of the first side of the 6SN7 to the other, a plate resistor for the detector once again chosen with the help of the tube manual, an RF choke between the low end of that and the power supply to keep from having any RF getting in there and a bypass capacitor to ground for good measure.<br />
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Time now for " smoke test number 2." Power came up, volume came up and a little louder hiss came from the speaker as the volume was brought about a third way up. Then the regeneration control capacitor was rotated to more messed and there was soon the expected "plop" sound in the speaker with a somewhat louder rushing sound as the stage went into oscillation. That meant that the 50-50 chance of getting the polarity of the tickler coil connected right was successful.<br />
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Now was the time to see if something could be heard. I set the main and bandspread tuning capacitors to mid range and brought a jumper lead to my 80-meter windom antenna over and plugged it into the SO-239, met with a satisfying crackle and increase in noise. The raw lead from the antenna was fed into the radio, not through my antenna tuner as I usually did for the ham rig, the idea being one less thing to tune to get things to the point of hearing something.<br />
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Of course, I had no idea where I was frequency wise. As I swept the main tuning back and forth, I ran into some cw signals, easily identifyable as maritime shore stations ( this was back in the 90's when many were still on the air) The stability was not too bad and callsigns for WLO and KFS were heard. Perhaps the 8 MHz marine band? Tuning toward less capacity and thus higher frequency, I soon ran into several broadcast stations, marked by whistles as the rig was still in oscillation. Backing off the regeneration control took away the whistle and let the audio of the signals come through. I hit one with rather recognizable music style and rested there a minute and soon was able to confirm that I must have been on 9420 as it was indeed the Voice of Greece, or as it was known then Foni ti Helladis ( if I remember right ) Tuning up through several stations, then hitting a stretch of blank space, there was then the unmistakable WWV. So the point on the dial corresponding to "70" was obviously 10 mhz. I was well on my way of finding my way around the dial.<br />
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Tuning up a bit further, I hit as expected an SSB signal. Tuning these with a regenerative receiver is a real trick. You have to be in feedback but not too much, and you have to tune carefully. Using the bandspread control with a little touch and release as there was still some hand capacity frequency pulling affects, it was determined that the station was transmitting aviation weather. New York Aviation Weather! There was still significant drift, but I would never have expected full communication grade stability from this thing.<br />
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Tuning up higher, I ran into the ( still to this day for me) unidentified radio teletype signal just inside the 30 meter ham band and a few cw signals.<br />
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Obviously the thing was working and I had traveled back in time to my childhood...sort of. There would be more experimentation and some real DX tuning another time, but it was late and dinner had been missed, and there are priorities. I will share more of the DX adventures with the rig dubbed Little Howler II at another time.DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-8861664069637261222019-12-29T11:12:00.000-06:002020-01-04T06:38:59.314-06:00Is It Worth Digging into MW today?We all get used to the idea of band conditions changing while listening on HF. The different bands are different by time of day or position of the sun, conditions make long, slow changes with the sunspot cycle or with the effects of solar weather. Aurora can upset the applecart of the time-of-day changes. Changes on HF frequencies are accepted as the norm and can come swiftly and suddenly.<br />
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Why is it, then, that it is difficult to imagine that happening on the medium frequencies? Is it because we are used to listening to them with the expectation that our usual, local stations will always be there? Because most of the time we are looking for something that is not DX, but something that is within groundwave range and dependable?<br />
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Sometimes, even those of us who have been digging out DX there for years have not noticed the day-to-day changes, chalking up hearing different stations on the same frequency to other factors, perhaps even using a loop or other form of directional antenna.<br />
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Truth be told, there can be tremendous differences from one day to the next, particularly during the grey hours of dusk and dawn. For me, this realization came about fifteen years ago when I began doing quick band scans while commuting to work. Because of the relatively short commute time ( not saying this to yank the chains of those with long drives each morning) of only about fifteen minutes in my previous job and less than ten minutes in my current one, I slipped into the habit of punching up a series of " regulars ". I had a list of a dozen and a half or so of stations that I would check in sequence while driving to work. It, thus, became easy to notice any sudden changes from day to day.<br />
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There were also the seasonal changes among these same stations as sunrise time changes throughout the year. These changes are gradual and through the year allow different signals to be heard on the same frequency as day light and darkness trade places from being east of me to west of me, or vice versa, as the seasons change.<br />
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But these seasonal changes are not what I am talking about. They are the sometimes wild differences from one day to the next at the same sun-time. <br />
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Sometimes they are measurable against a ground wave, or semi-local station. An example of this for me is WTAW in College Station, Texas on 1620 kHz. Even though this station is 90 miles away, even on its night time power of 1 kw it is audible here in Waco on the radio in my 1999 Ford Ranger pickup. In the winter when I am driving to work maybe an hour before sunrise, Cuba is audible in the background. Some mornings it will be just audible in the background, but some mornings it will be blasting in almost enough to cover WTAW up completely. ( By the way for those wondering what a radio station in Texas is doing with a "W" prefix callsign, it was licensed in 1922 before the dividing line of the Mississippi split up "K's" to the west and "W's" to the east. The station has changed frequency several times since then)<br />
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The same can be said for watching what happens with KSKY, 660 in Dallas, 90 miles in the other direction. On their reduced nighttime power, they are marginally audible even at night, but some mornings or nights other stations cover them, others they don't. On this one, unlike WTAW where there is one dominant station that threatens to cover it, on 660, different stations may appear over them on different days, showing heightened prop in slightly different directions from one day to the next at the same sun time.<br />
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On other frequencies, skywave differences can be more dramatic. In the mornings, on 890 some mornings WLS from Chicago will dominate, while on others some station from Mexico will cover it. At night, it might even be a Cuban, depending on the band conditions.<br />
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In fact, the Chicago station "skyline" can offer some real comparisons. There are 50 kw stations that are capable of good signals into central Texas on 670, 720, 780, and 890. If prop is good from the north, they will all be audible. Other mornings, there may be stations either sharing the dial spot with them or completely covering them up. It is interesting to note that at sunrise, the lower frequency ones will disappear first, often with WLS on 890 being the only one " left standing" as the sun comes up.<br />
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The sunrise effect also shows up on the stations from Mexico as well, with the lower dial position stations such as 540, 730, 900, 940, 990 disappearing in that order while 1000, 1030, 1050 and 1060 and particularly 1570 still booming in even after the sun is fully up.<br />
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Sometimes the band just before sunrise will show what amounts to "directional" characteristics, with all of the Chicago stations coming in well and the western stations such as KHOW, KOA and KSL being below par. Some mornings it will be the opposite, even from one day to the next at the same sun time.<br />
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It must be cautioned that in all this comparison, signals of different stations on different frequencies not be compared directly to other stations on other frequencies because there can be notable differences in facilities, power, or directivity of transmitters. However, what can be noted is the relative difference between the signal strength of each station with what it appears to be on other days and noticing the different " amount of difference" between each when compared with itself.<br />
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For example, to show a difference in band conditions that is frequency dependent, one might note that the Chicago 780 station might be a tremendous difference ( say four of five s-units down in looking at a meter) while the 890 Chicago station might be only down three s-units from what it was the day before.<br />
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Or perhaps the 890 Chicago might be very low compared to the day before or even covered by Mexico while KSL Salt Lake on 1160 might be much stronger than it had been the day before at the same time.<br />
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Sometimes aurora can cause some really unusual effects, such as the more northern stations disappearing completely, leaving new or previously unheard stations from other directions in the clear.<br />
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On a drive-to-work day noticing is about all that can be done as there is really no time to tune around and check other frequencies. If one is home or otherwise has the time to tune around it might be different.<br />
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In any event, checking the "regulars" can be a clue whether its worth the effort to look around or spend the time doing something else, perhaps tuning around on HF.<br />
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For me here in Central Texas, there are several either/or frequencies to check. On 560, is it semi locaI in Beaumont or Denver? On 630 is it San Antonio or Denver. On 580 is it WIBW or XEMU?<br />
Is there anything showing up behind KLIF Dallas on 570 or behind KTRH Houston on 740? On 940 is it Midland or Mexico City? You get the idea. If things are out of the ordinary, it might be time to fill up the coffee cup and dig in.<br />
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There is one other "beacon" I use here to determine how I spend my predawn time on the weekends. I tune up to 2850 khz and check on the strength of the 50 kw station in Pyongyang, North Korea.<br />
Many might not even know such a station is even audible in the US. However,it can be counted on to at least be detectable almost every morning. Some mornings it will be very strong. If it is strong enough clearly hear speech and music, it is worth spending time to check for trans-Pacific stations on MWcoming through.<br />
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I am not sure how all DX-ers are fixed for time but I am sure most find other things that compete for their time. For me, it is a full time job, family, household chores, contract work and writing (do I write for this blog or play with the radios!!) For others, there are surely other things that vie for your attention. Sometimes a little scouting about may help you decide how the time available might be spent. Do you look for MW DX, tune up through the shortwave bands or if its really bad, give up and turn on the telly (nooooooooo!!!!)<br />
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Even on the bad days there are things the died-in-the-wool DX-er can do, but we can look at that another day. Until then, good listening!!! DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-37770911798235695332017-08-13T11:19:00.000-05:002017-08-13T11:27:02.403-05:00W6LVP Loop Trial<br />
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After reading many reports about some of the "new" broadband, amplified loops and having had considerable experience with large unshielded tuned loops, and also having a vacation coming up to a coastal area, I thought it might be a good time to spring for one of them and give it a try, especially given the increasing and intermittent high noise floor in my neighborhood.<br />
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For ease and quick shipping and a somewhat lower price, I chose to go with the W6LVP loop after seeing several good reports among the Facebook DX groups that I have been frequenting.<br />
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I will say that the customer service, method of secure payment and swift delivery was very good and the antenna arrived in short order, well packed and of apparent good construction. Assembly, such little of it that there was, was very simple and intuitive. The antenna is very light and is attractive.<br />
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I fired it up inside the shack only a couple feet off the floor and fed it into the R-75 only a few feet away. the power supply was very quiet and there appeared to be no noise coupling from it even with the close proximity that I found it to be to the loop in the initial test.<br />
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Noise inside my house is a bit high due to multiple cell phone chargers, wifi, televisions, cable boxes and computer power supplies, but with judicious rotating of the loop, noise was lower than the vertical out in the yard and considerably lower than the sloper. Comparing signal strength of WWV and CHU showed about three S-units down from the outside forty foot vertical over 60 buried radials, but due to the reduced noise, they were all at least as readable on the loop inside.<br />
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Noise on the MW broadcast band and Low Frequency band was comparable to the vertical. To be totally fair, rotating the loop inside the house showed noise coming from various locations, with two of the main sources just about 90 degrees apart, so nulling both would be just about impossible no matter how good the loop would be.<br />
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The next day, I mounted the loop on a temporary mast in the back yard about 20 feet from the house. It was up about fifteen feet above ground in the same general area of the yard as my vertical ( about ten feet away) and about 20 feet east of where the sloper traverses the yard.<br />
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Firing it up at that location gave it a much better chance of showing off its performance. In fact, it was a whole different world from when it was inside. Nulling the major noise source was much easier, though there seemed to still be a secondary noise source whose null would require a position mutually exclusive to the position for nulling the worst noise source.<br />
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The first test run was done in the MW broadcast band at 0000 GMT July 23. This is over an hour before dark at my location in Woodway, on the west side of Waco, Texas. To get an idea of just where I am, if you look at a map of Texas, look on the west side of Waco along Highway 84, a couple miles west of its intersection with Loop 340/State Highway 6. The following signals were logged as ground wave signals on the loop feeding the R-75:<br />
XEMU 580 kHz 5 kw Piedras Negras, Mexico S-5 and steady<br />
KLIF 570 kHz 5 kw Dallas, Tx S-9+10 db<br />
KLBJ 590 kHz 5 kw Austin, Tx S-9 + 20 db<br />
KTBB 600 KHz 5kw Tyler, Tx S-5<br />
KILT 610 kHz 5 kw Houston, Tx S-7<br />
KESB 620 kHz 5kw Dallas, Tx S-8<br />
KSLR 630 kHz 5 kw San Antonio, Tx S-7<br />
Unk 640 kHz 1 kw Norman, Oklahoma S-5<br />
KSKY 660 kHz 20 kw Dallas, Tx S-9+20 db<br />
KKYX 680 kHz 50 kw San Antonio, Tx S-8/S-9<br />
KSAH 720 kHz 10 kw San Antonio, Tx S-8<br />
WBAP 820 kHz 50 kw Fort Worth, Tx S-9 + 40 DB<br />
KONO 860 kHz 5 kw San Antonio, Tx S-7<br />
Unk 930 kHz 5 kw San Antonio, Tx S-7<br />
WOAI 1200 kHz 50 kw San Antonio, Tx S-9<br />
KRZI 1660 kHz 10 KW Waco ( local) full scale<br />
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These were logged in a quick sweep mostly of stations I could identify by presence to get a quick idea of what was going on via groundwave before too much night effect prop would begin.<br />
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At 0100, still a bit before sunset and still full sun at the WWV transmitter site, a quick sweep of time and frequency stations yielded the following:<br />
2500 WWV S-5<br />
3330 CHU S-4 ( their transmitter site in darkness)<br />
5000 WWV S-9<br />
7840 CHU S-7<br />
10000 WWV S-9+20 DB<br />
14670 CHU S-7<br />
15000 WWV S-9+10DB<br />
20000 WWV S-7<br />
25000 WWV Just audible carrier<br />
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The R-75 in all of these tests was being run with neither pre-amp on. Ambient noise on the loop was about S-1, while on the vertical was S-3. It should be noted that the vertical had been put up in the quietest spot in the yard by walking a portable receiver around tuned to 500 kHz.<br />
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A quick tune around showed the Voice of Greece, a strong evening regular on 9420 at S-9+20 DB. A check of Radio Encyclopedia from Cuba on 530 kHz showed it at S-7, well above the noise and listenable. On the vertical it usually runs S-9 but with some noise in the background.<br />
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A quick test of the low frequencies showed, as expected, it was well too early for the European and African Long Wave broadcasters to be heard. I quickly ID'ed a few non-directional aircraft beacons:<br />
ARM 245 kHz Wharton, Texas S-5 ( about 200 miles)<br />
PQF 248 kHz Mesquite, Texas S-7 ( about 100 miles...Mesquite is on the east side of Dallas)<br />
ROB 400 kHz Robinson, Texas S-9+20 db ( local NDB 10 miles away)<br />
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A quick ham band test in the 40 meter cw portion showed:<br />
0227 GMT OK2RRR 7007 kHz Czech Republic RST 579<br />
0238 GMT F5IN 7011 kHz France RST 579<br />
0247 GMT W0LI 7017 kHz USA RST 589<br />
0248 GMT K9OM 7017 kHz USA RST 599<br />
0249 GMT W7FW 7018 kHz USA RST 599<br />
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Again, these were on the R-75 with no extra preamps on and with 250 hz filters in.<br />
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This being at the end of a long day and with other evening chores still ahead, this was the end of the first days testing.<br />
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The next day ( July 23, 2017) allowed time for a little more testing under daylight conditions. Unfortunately my operating set up did not allow quick A-B testing between the loop and the vertical because I have no remote antenna switching and I was actually using the feedline that normally goes to the vertical to feed the loop. The transmission line is about 100 feet of RG-8 X that is routed in an indirect route along fence lines to allow the shortest run across open lawn to the antennas. The RG-8X is not buried.<br />
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In a run beginning at 1436 GMT or about two-and-a-half hours after local sunrise, a run of the time and frequency stations yielded the following:<br />
25000 kHz WWV S-5<br />
20000 kHz WWV S-7<br />
15000 kHz WWV S-9<br />
14670 kHz CHU S-4<br />
10000 kHz WWV S-9 ( No WWVH)<br />
7850 kHz CHU S-4<br />
5000 kHz WWV S-8<br />
3330 kHz CHU inaudible<br />
2500 kHz WWV Just audible carrier<br />
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A run through the 20 meter amateur band resulted in a logging of showed numerous USA stations at S-9 or better At 1444 I heard VE2WU calling CQ on 14017 about S-5 followed by XE2AAW in Mexico at S-7. No Europeans were heard in a quick sweep. WRMI on 9455 was S-9 at 1448 GMT. At about this time, rains were coming in and the loop was taken down from its temporary mast because the connections had not been waterproofed for this quick test. The next few days saw several periods of thunderstorm activity, so testing was pretty much halted. The rest of the week was also taken up by preparations being made for the vacation trip that would include testing the antenna at the Gulf Coast.<br />
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This would be a real test as we were going to the coast in a passenger car rather than our usual Chevy Suburban and would have no room for large mast sections usually carried on the luggage rack on the roof of the Suburban. The loop would be the only antenna taken.<br />
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We arrived at our coastal location about midday July 31. Radio activity would take place in the environment of family activity, so it would not be a full five days of all-out testing but it was hoped that a fair amount of " wringing out" of the antenna would take place. It was mounted on a camera tripod with a short piece of PVC pipe extending above it to keep the loop away from the metal of the tripod. The antenna was set up on a balcony about 15-18 feet above the ground and about a hundred yards from the water.<br />
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The location was at Crystal Beach, Texas on the Bolivar Peninsula about 12 miles east of Galveston, Texas.<br />
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The first listening came late in the afternoon of the first day and was a short one due to other activities including unpacking, running errands to a local grocery to stock up on supplies and the first steps into the salt water ( priorities!!!)<br />
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A quick check at 2300 GMT showed our old favorite, the Voice of Greece on 9420 at S-9+20 db.<br />
WWV on 10 MHz was S-9 with QSB and on 15 mHz was S-5 with QSB. A quick check of a few Medium Wave stations showed WTAW on 1620 KHz, 10 kw, from College Station, Texas ( about 160 miles) S-9 + 10db. KRZI on 1660 from Waco, also 10 kw was S-9, and while they were still on daytime power, there was some evidence of night effect as there was some QSB. KOGT 1600 from Orange, Texas with 1 kw about 75 miles away was S-9+10 db, but it should be noted that it is almost a water path from that location. Thus ended the first evening of testing with swimming and dinner taking over!<br />
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With testing the next morning some disappointments began to show up. It was obvious that there was difficulty in nulling noise and many signals were just not what they should be. particularly signals to the north were poor. It was then discovered that the reason for this is that the beach house had been built with metal studs in the walls and the wiring for lights on the balcony were running within a foot of where the loop was set up. Tilting the loop to get it away from the walls of the house...so let it " see around the house" as it were and to get it away from the house wiring helped considerably. Signals via groundwave from medium wave stations to the north and east of us jumped 20-25 db or more and the noise was nullable. This would appear to be a consideration for anyone planning to use one of these loops made by any manufacturer. Metal framing might be a bit of a problem, though other testing with the loop inside and near windows without metal screening outside showed fine results in the direction of the opening. Turning the lights off on the balcony where the wiring ran so very close to the loop took care of most of the noise problem. It would appear that the antenna will work very well inside if some care is taken with placement. No antenna can perform miracles if not given a chance!!<br />
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After the antenna rearrangement, reception on the low frequencies was quite good. The dial was full of low frequency non directional beacons, with dozens heard very well beginning the next morning about 1600 GMT ( 9 a.m. local time) with many heard from all over Texas, Louisiana and a few from Mexico. The noise floor after antenna rearranging and nulling was about S-2. The carrier for the WWV station on 60 kHz was even heard.<br />
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Daytime reception on medium wave was quite good. A sampling of more " interesting" MW loggings that mid morning ( starting about 9:30 a.m. local):<br />
KTSA 550 5 KW San Antonio S-7<br />
KLVI 560 5 kw Beaumont, Tx S-9 + 30 db<br />
KLIF 570 5 kw Dallas, Tx S-5 <br />
KJMJ 580 5 kw Alexandria, Louisiana S-4<br />
XEFD 590 5 kw Reynosa, Mexico S-9<br />
XEGH 620 1 kw Reynosa, Mexico S-7<br />
KSKY 660 20 kw Dallas, Tx S-6<br />
KKYX 680 50 KW San Antonio, Tx S-9 + 10 db<br />
WQNO 690 10 kw New Orleans, La S-5<br />
KEEL 710 50 KW Shreveport, La S-5 ( a loooong way for daytime groundwave!)<br />
KSAH 720 10 kw San Antonio, Tx S-9<br />
KTRH 740 50 kw Houston, Tx Full scale.<br />
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Rotating the loop seemed to indicate a pretty broad main lobe but a fairly deep and narrow null.<br />
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I ran through 31 meters about mid afternoon, at a time I thought would be before the night time enhancement of those frequencies with a later run through the same band near sunset. Here are a few samples with the sweep beginning at 2000 GMT, or 3 p.m. local time ( actually 2 p.m. local sun time given that we are on daylight savings time...something easy for me to forget!) This was with the loop attached to a eight foot long piece of PVC pipe and extended out from the balcony to get it away from the metal in the walls and the wiring in the ceiling.<br />
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V. of Greece 9420 S-5<br />
Voice of Turkey 9460 S-7<br />
R. Saudi 9555 S-8<br />
R. Marti 9565 S-7 plus jamming...could null the jamming!<br />
Voice of Turkey 9635 S-5<br />
R. Guinea 9650 S-4<br />
R. Saudi 9675 S-7<br />
R. Saudi 9870 S-5<br />
V. of Greece 9935 S-5<br />
WRMI 9955 S-9+10db<br />
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The noise floor was about S-2 with the loop extended about four feet away from the balcony.<br />
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Another run through 31 meters beginning at 0030 GMT or 7.p.m. local or a little over an hour before local sunset with the loop in the same position as above:<br />
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V. of Greece 9420 S-9+20 DB<br />
WRMI 9395 S-9<br />
WBCQ 9330 S-9+10 DB<br />
Strong rtty sig 9317 S-9<br />
WINB 9265 S-9+10 DB<br />
Nauen, Ger. 9450 S-7<br />
WRMI 9455 S-9<br />
CRI Kashi 9470 S-6<br />
Issoudon 9490 S-9+20 DB<br />
R. Transmundial 9530 S-4 (Brazil)<br />
R. Havana 9555 S-9<br />
R. Boa Ven. 9550 S-5 Brazil<br />
CRI/Rom. 9570 S-9+ 20DB<br />
CRI/Cuba 9580 S-9+ 10 DB<br />
CRI SP kasha 9590 S-4<br />
R.Cancoa N. 9675 S-5 Brazil<br />
RRI 9730 S-9+ 10 DB<br />
V. of Turkey 9830 S-9+ 10DB<br />
VOIRI 9880 S-5 ( Iran)<br />
V. of Greece 9935 S-9+10 DB<br />
These are all on the R-75 with no extra preamp turned on.<br />
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Later at 0200 R. Sonder Grense on 3220 from Meyerton, S. Africa was in very solid at S-9 and listenable without objectionable noise.<br />
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I hope this is not getting too boring with too much listing, but I figure that this is the best way to show the performance of the antenna, particularly for those in the Central US and hopefully for those elsewhere looking at a map and sort of imagining tuning and listening get some idea what one could get out of this antenna.<br />
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Below is a quick run through of the "usual" Mexican and Cuban MW stations heard nightly, previously on wire and vertical antennas beginning at 0250 GMT just getting into post dusk darkness:<br />
XEX 730 Mexico City S-9+20 DB<br />
CMBC 890 Cuba S-7<br />
XEW 900 Mexico City S-9+20 DB<br />
XEQ 940 Mexico City S-9+20 DB<br />
XEOY 1000 Mexico City S-9+10 DB<br />
XEG 1050 Monterrey, Mex S-9+20 db ( 150 kw)<br />
XEEP 1060 Mexico City S-9+ 20 DB<br />
XERF 1570 Ciudad Acuna, Mx S-9+30 db<br />
R Encyc. 530 Cuba S-9<br />
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All of these signals are more than comparable to how well they are received at home on both the vertical and the sloper, again with noise floor measured at 520 kHz of S-2.<br />
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The last " acid test" I gave the antenna was the look at the sunrise Pacific/Asian opening the next morning beginning at 1130 GMT or 6:30 a.m. local time, just as light is beginning to appear on the horizon. Noise floor measured at 2800 khz S-2<br />
2850 KCBS North Korea S-4 very readable<br />
2500 WWV S-8 with WWVH audible in background<br />
3320 Pyongyang BC S-4<br />
3325 Bougainville and Indonesia mixed S-5 "bouncing"<br />
3480 Voice of the People S Korea S-5<br />
3910 Voice of the People presumed S-5 and jamming<br />
3925 R Nikkei S-5<br />
3930 Voice of the People S-5<br />
3945 R Nikkei S-5<br />
3985 Echo of Hope S-5 and jamming<br />
4055 R Verdad S-7 QSB ( interesting notably with not as good a signal as at home!)<br />
4212 WLO CW/SITOR s-9+10 DB<br />
4735 R. Tarma Peru S-4.<br />
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There were some thunderstorms that developed in the area the next couple days and this led to disappointment in doing more low frequency work and I did not hear any of the European or African Long Wave Stations or MW stations.<br />
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Overall, for its size, the antenna performed admirably well. It was great to have an antenna to take on a trip that was not a huge chore to pack and set up. It might have been good to have some mast sections that could have allowed the antenna to be set up at a distance from the house and more in the clear.<br />
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I have noticed the same here at home. While it works well indoors, at least much better than an indoor random wire, it does much better outside and in the clear. Getting it up fifteen feet or so really seems to help. The next plan at home is to put it up on a telescoping mast up about thirty feet.<br />
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One observation is that other metal objects very near do seem to affect the ability of the loop to null noise. Dropping the wire sloper at home that had been running near it greatly reduced the noise that apparently was being coupled into it. If one is using one of these type loops it would proibably be worth the effort to keep it at least a moderate distance away from other antennas, particularly large wire antennas. If those other antennas pick up noise where they run, they could couple that right back into the loop or provide an additional place to be nulled, thus " nullifying" one of the advantages of the loop.<br />
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The loop does result in somewhat lower S-meter readings on some signals, but the lower noise floor more than makes up for that.<br />
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QSB does seem to be more pronounced than on the larger antennas but that is probably just a result of the smaller aperture and less of a "diversity" effect thereof.<br />
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During the test period, I noticed that the antenna did seem to perform better on the lower frequencies, but that might easily have been the result of band conditions, so consider that a caveat.<br />
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I was hoping to hear some DX on 160 meters, but during the week and during a non contest period there is not a huge amount of activity on that band, so that should not be misconstrued.<br />
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All in all, this antenna has proved worth the expense and for those with limited space or even living in an apartment, I can highly recommend it as a way of getting some reasonable DX. If you have a balcony, all the better...and if you can get it extended out beyond the balcony, even better yet. As with any antenna, giving it an even chance to work by putting it in the best possible location is a given. If you are in a home with metal framing ( aluminum studs in the walls, etc) do your best to get it at least near a window without metal screening.<br />
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I am already planning a way to get the radio and antenna out totally away from wires and walls. Running the R-75 and the loop both off a 12 volt battery is easily possible.<br />
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One note: Despite being in the " hot lobes" of directional antennas from three different 50 kw stations including one that effectively "pinned" the S-meter on the R-75 ( OK, drove all the lights on...) there were no overload issues. The Galveston station on 1540 khz runs 2500 watts but its directional had its main lobe right over our vacation location with only salt water between us and it was not a problem.<br />
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There is always a risk in evaluating an antenna over a short period of time given how band conditions can vary. That goes not only for this report or for any antenna you might try or put up. Poor bands can make the best antenna seem lousy on the first try and listening with extra care on a new one can sometimes give an impression in the other direction. Always give one time, and particularly with small antennas like loops, try different locations and give them an even break to give you what you want.<br />
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Again, I hope the station listings were not too boring, but figured it was the best way to show what the thing did. As always, comments welcome.<br />
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WWCR 9980 S-9<br />
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<br />DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-42474075595853592952017-08-12T11:23:00.000-05:002017-08-12T11:23:25.923-05:00By What Path Do They Get HereI was asked in one of my Facebook groups how signals travel to their destination, or by what path do they come. The simple answer is " by a Great Circle path."<br />
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What does this mean? Well if you think back to geometry class ( I know that is asking a lot!!) the definition of a great circle on a sphere is " a line on the surface of the sphere defined by the intersection of a plane passing through the two points in question and through the center of the sphere"<br />
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OK, so that is a little esoteric. Think of it this way. Take the equator line and tilt it so that it passes through the two points, or cities, that you are looking at.<br />
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If you look down on the line while holding a globe, this path looks like a straight line. but if you look at it on a flat map it will look much different, most likely as a curved line. If you are familiar with what is known as a polar projection, or a flat map made up as a circle with the center being the north or south pole you can get a better idea of what is going on. A really good way to look at it would be if you could find a polar projection based on your own location. There are computer programs that can do this for you and I would be willing to bet with a little judicious searching on the internet you could find a website that can do it. You would just need your latitude and longitude to enter.<br />
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Sometimes the direction from your place might be much different than you would intuitively think.<br />
Like who would think that the beam heading for Alaska and Japan would almost be the same from Central Texas. Of that the beam heading for Europe and East Africa would be almost the same.<br />
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You will notice if you do this mental exercise or even look at a globe with the two points actually on the equator that there are two paths between the points: the short one and the long one. Thus the definition of " long path" and " short path".<br />
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Logically the shortest one is the one by which the signal you are hearing arrived, and most of the time this is true. However, there are times and conditions under which the signal can arrive the other way round, or in some cases by both.<br />
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Which way it comes depends upon the time of day, frequency and general band conditions. If you are where I am, in Central Texas, the shortest distance to Australia is to the southwest over the Pacific Ocean. If I want to hear or work an amateur station in Australia on forty meters, the best time for short path is early in the morning my time. That insures that the signal will have a darkness path most of the route. Often the window is short depending on where in Australia the station is located, because the sun will be either just going down or has been down a little while the sun is almost about to come up here. Propagation on forty meters ( 7 MHz) the other way around in the morning my time is simply not going to happen because that path is in full sunlight most of the way.<br />
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But let's take a look at " the other end of the day." Just before sunset in Texas, in some parts of Australia the sun is just rising, or just about to rise. The path the long way round is in darkness most of the way. Prop on forty meters usually lasts a little beyond sunrise at most locations, sometimes by an hour or more. If on that particular day, conditions are such that the Maximum Useable Frequency happens to be fairly low. it just might be that prop can begin a little before sunset and continue until a little after sunrise, just enough to allow the signal to get through, and you get your signal via long path!<br />
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Now what direction is the signal going? Logic might try to tell you to the southeast from Texas, but that is not correct. The signal still follows the Great Circle path, which means it goes Northeast, up and over Europe, then down toward Australia.<br />
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Long path prop does not happen every day or on every frequency. There are a number of factors that might determine whether it will occur or not.<br />
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First, for the lower frequencies, there still must be darkness over much of the path. There might be some stretching at either end with some light if the first hop could still be in darkness. This can occur if the frequency involved is at the higher end of the range that can be propagated in darkness. For example, my most frequent success on the amateur bands for long path prop to Australia from Texas has been on the 30 meter band. There are times that rather long hauls can be made in the late daytime or near dusk that might make the first hop possible even a couple hours before sunset. The subsequent hops would then be in darkness.<br />
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For shortwave listeners, the closest approximation might be the 31 meter broadcast band. In the winter hemispheres, 25 meters might be too high for good prop after dark at the higher latitudes and would not make it, but 31 meters might. We all know that 31 meters does well until a good ways after sunrise as evidenced by NHK from Japan and Radio New Zealand being listenable after sunrise in North America ( and of course, the now gone Radio Australia on 9580 was often listenable well after sunrise while it was still on the air)<br />
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There are times that the 40 meter amateur band and the 41 meter shortwave broadcast band can provide the same kind of performance. The only difference is one must be much closer to darkness for it to work.<br />
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There may be exceptional times where prop can occur over both paths at the same time. I have noted this most often at higher levels of sunspot activity on the higher bands that can still sustain prop at night. This kind of prop is characterized by a pronounced echo on the signal brought about by the different transit times for the two paths. My earliest experience with this occurred listening to the VOA relay station in the Philippines back in the early sixties.<br />
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As a side note, echo does not always indicate both long and short path prop. There are also times that I have noted Pacific or Japanese stations with pronounced echo in the mornings that is the result of something else altogether. It is a phenomenon known as " Backscatter". This occurs most often when a station in the Philippines or Japan is beaming a signal away from North America. Some of the signal arrives direct path off the back of the antenna. ( One must note with care when looking at beam headings listed for broadcasts. Just because a certain beam heading is indicated does not mean that there is no signal sent in other directions. Even if the front to back ratio of an antenna array is 20 db or even more, if the station transmitter is using high power in the 100-250 kw or more range and the effective radiated power in the main lobe is nearly a megawatt, 20 db down in the opposite direction is still a power level high enough to provide a fair signal. Twenty db down from an ERP of a megawatt is still 10 kw!)<br />
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In backscatter, signal that arrives at a distant point from a transmitter often has some bounced back toward the transmitter, and if the prop is good, can hop again toward a listener off the back of the antenna, too. The difference in transit time can give the echo effect. Some times because the backscatter signal has originally come off the front of the antenna with much greater power and the "direct" signal was radiated with less power, sometimes the echoed signal can be noticeably stronger than the direct signal, giving a really strange effect of the echo being louder than the first part you hear. Sometimes this effect is so pronounced that it can be difficult or impossible to understand the words being spoken. On a cw amateur band signal, the delayed dits and dahs can fill in the spaces and make the signal absolutely impossible to copy.<br />
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This is a bit of a digression, but because backscatter is an interesting phenomenon perhaps it should be included here. And in a way it fits because it can provide an anomaly in the direction from which a signal appears to come. This happens most noticeably on the ham bands, but conceivably could happen with broadcast stations, too.<br />
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There are times when a relatively nearby station--that is, one too far away to be heard via groundwave but within the "skip zone" or area where the signal is usually not heard because it quite literally "skips over" the receiving site--can be heard, usually with a fairly weak and often very fluttery sound. What is happening in this case is that the signal is being heard totally via backscatter. That is, the signal is going from the originating signal through the first hop distance, then when it hits the ground or water, while a good bit of the signal goes forward for the next hop, some of the signal sort of "splatters" and usually most of it goes back in the general direction from which it came, making it audible in the general region where it originated.<br />
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A good example of this would be a Texas station being heard on 10,15, or 20 meters by other stations in Texas and Louisiana perhaps well beyond groundwave range but " too close" to be heard by skip. It has been my general observation, by no means meaning that this is the only time it happens, that this occurs usually right before the band goes out to the original target area.<br />
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When this happens, some of the backscattered signal might go off in a range of azimuths, allowing the station to be heard in other areas besides where it was originally targeted or where the "regular skip" path would have taken it. This would lead a receiver of the Texas signal in, say, Mexico or Central America, to say it appeared to have come from the west or southwest, making it appear that the signal came by the odd path if the receiving station were using a rotary beam of some kind. It would peak up as coming from the point of the back scatter rather than from whence it really came.<br />
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This is where I believe the fabled phenomenon some times called " one-way skip" comes from. If the station hearing the Texas station via backscatter were to try call or answer the station, the contact would never be made because the chances of the answering station making the trip back to the original station via backscatter from a different angle would be very small indeed.<br />
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Other echo effects can occur on signals whose paths take them through the auroral zone in the arctic.<br />
Signals get tumbled and jumbled and can take on a watery or echoey sound. This often happens in the amateur bands in the Central US when listening to signals from Sweden, Norway, Finland and north-central Russia. As in the case of backscatter, this can make a phone signal hard to understand or cw all but impossible to copy. On the amateur bands, when trying to work a station in Scandanavia or northern Russia on cw under these conditions, the old school guys know the thing to do is to SLOW DOWN and put more spaces between characters so the echo doesn't kill your intelligibility. This is why I always keep a straight key at the ready along with my Vibroplex bug and electronic keyer!<br />
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Gray line prop is another condition that can often make signals appear to come from a different direction than they " should" There are lots of theories about what brings about so-called gray line enhancement, in which signals seem particularly strong along the boundary between daylight and darkness. I make no claims to understand with any certainty what actually occurs, but have learned to take the " bonus " signals or signal strength and enjoy it. There are times when the signals seem to come from other directions than they should. Sometimes the best thing to do is just log 'em and don't worry about it. If using a directional beam antenna, just rotate for best signal strength and don't look at the azimuth indicator. The bottom line: get them in the log!<br />
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One other time in which signals can appear to come from a different direction than they should is during Sporadic E propogation on VHF frequencies. I have noted times when it almost appears a signal has taken a right or left 90-degree turn when arriving.<br />
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This happens when the signal arrives by multiple hops. Sporadic E occurs when highly ionized patches or clouds form in the mid level of the ionosphere with the ionization levels high enough to provide reflection of signals well into the VHF region. Sporadic E can also extend into lower frequencies, but usually only down to 25 MHz or so.<br />
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If there happens to be two different sets of E layer clouds and IF a signal bounces off one, strikes the round in such a way as to scatter and perchance strike a second E layer cloud somewhat off azimuth from the original path, the signal path could in effect, be bent.<br />
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Sometimes during a really wild sporadic E opening one can almost wear out a good antenna rotator trying to figure out where best to point the antenna. Again, its often best to just leave it where the signal is best readable and not worry about it. Truth be told, often Sporadic E signals come down at such a steep angle that they strike the antenna from high above and it probably matters not which direction its pointed.<br />
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How do we predict these things? Well, that could be a really tricky business. One could spend so much time trying to do it that there would be no time left for DX-ing. And perhaps this is where differing philosophies come in. Whether it be double hop Sporadic E, grey line prop, long path prop or whatever, there are some who would try to assign numbers, develop models, look at the physics of the thing and basically geek themselves almost into a coma trying to predict and figure them out or explain what's happening.<br />
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It is my personal feeling that while this is well and good and a great academic exercise, for me THIS IS A HOBBY! While there are some fishermen who do the same thing, others just go out and fish. I go out and listen. For me, what is more fun is to turn on the radio, tune around and get a feel for what's happening and then intuitively shop for the best DX.<br />
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I have often said that DX-ing is a lot like fishing. One learns to read the signs and then just know where to look and how to look. Experience has taught me that some indicators indicate certain conditions and to let that guide where I look. There are some tools that can help a bit, like the prop forecasts. Though if I had paid attention to prop forecasts that called for poor conditions or some kind of disturbance, I might never have turned on the radio and missed some great stuff. But I have learned that when there is supposed to be no prop, often folks do just that and there is little activity. But if there is a little atmospheric noise and one tunes around, someone might just find somebody rare and distant hopefully calling CQ. I well remember stumbling across my first Guam, Johnson Island, Banaba, Christmas Island and a few others just that way!!<br />
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Sometimes another "new school" barometer to look at is DX Summit or some of the other DX reporting sites that post real time signal spots. Take a look and just see where the stuff is coming into various areas and on what frequencies. This is even useful to the non ham or listener who is not interested in ham stuff. But what is happening on the ham bands can be a really good barometer on what is happening on the nearby shortwave broadcast bands. Forty meter spots being a good barometer for 41 meters and to a lesser degree for 49 meters. Twenty meter and seventeen meter spots are good indicators for 19 and 16 meter shortwave stations. Thirty meter spots are good for 31 meter shortwave conditions and to a lesser degree 25 meter shortwave broadcast spots. Sixty meter spots are good for, well, the 60 meter shortwave band. And so on.....<br />
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But I am wandering a bit off track here. Hopefully this will help some get a feeling about how things appear to me to work. This is based not on textbook theory, but over fifty years of observing what really happens out there. Sometimes it seems better not to worry so much about the why's of something and to just jump in and take advantage of it.<br />
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Good DX-ing to all, and as always, I am happy to hear from anyone with their own observations and ideas through the comments section of this blog or through the Facebook groups you can find me on.<br />
Don't forget, if the bands sound dead or the signals sound weak, don't turn the radio off-get in there and dig around. You never know what might be lurking in the radio shadows.<br />
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DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-16941365199116350102016-01-06T10:31:00.000-06:002016-01-06T10:31:01.118-06:00Dahlak Island Adventure-9F3USA/P1 In 1972-73 while assigned to Kagnew Station in Asmara, Ethiopia ( now Eritrea) I had some great opportunities for SWL and Ham DX. As part of the radio club there, I had the opportunity to operate the club station ET3USA. The club had a block of callsigns assigned to it that allowed a limited number of hams to operate under the license off post, using the callsigns ET3USB-ET3USF. This was in the early 1970's. Some of that activity will be the subject of future columns.<br />
Early in the Spring of 1973 I was approached by Mike Durbin, WA5TKC, with an invitation to join him and KP4CKX who also worked at facilities in Asmara in what he termed a " mini-field day" operation he had planned. Turned out, it was what amounted to a short DX-pedition to an island in the Red Sea.<br />
The plan was to go in late May to one of the islands in the Dahlak Archipeligo off the Ethiopian Coast near the port of Massawa. Mike worked the details out with the local government authorities, which was no mean feat given the political situation at the time. There was rebel activity in Eritrea at the time and any use of radios out in the field might have been suspect.<br />
All the hurdles appeared to have been cleared and early on a Friday morning, a group of us caravanned down the 72-hundred foot mountain to Massawa to catch our ride to the island. That drive was always an adventure in itself, being on a two lane paved road that would not exactly be considered a highway. It was a 110 kilometer drive containing 27 switchback turns.<br />
In addition to the three of us who would operate the radios, a group of a half dozen others were going along to go fishing. That helped spread out the cost of chartering the boat and also would cut down on the provisions we would have to take. The operation was going to basically be a long weekend, and would be nothing like the heavily financed trips taken by groups these days. I think we figured the total cost of the trip, including gas to drive up and down the mountain was about $300 US!<br />
All of the equipment taken fit inside one small footlocker. The radios were two Heathkit HW-101's, tube type rigs that ran about 100 watts out. There were two rolls of wire, some nylon rope, mikes and keys and paper for logging. ( No computers!!!). There was a 1 kw gasoline powered generator. Outside the footlocker, we carried three Jerry cans for fuels, a couple cans of oil and the antenna, which was a 14AVQ trap vertical that covered 40-10 meters. There were also a half dozen or so short poles that would make up a short mast.<br />
The plans were to operate one station at a time on 40-10 and to string an 80 meter wire for communication back to Asmara. Our ride out to the island would be on a 40 foot Arab fishing dhow powered by sail and small inboard engine. It would be about a four hour trip from the harbor to our destination. This would not be a luxury trip. Seating was flat on the open deck. Any cooking on board would be in a small sand pit on the forward deck!<br />
The first problem came after all the gear was loaded on the boat in the harbor. Government officials came by and wanted to inspect everything again. They wanted to do so out of our sight, so we went to a nearby restaurant and had an unscheduled early lunch break, followed by ice cream ( which for me turned out to not be a good thing later!!)<br />
About two hours later, we were finally able to leave the harbor. Water was smooth in the harbor, but not so much when we got out in the open water. Seas were a little rough, and for awhile it was great fun to stand in the bow of the boat and have the spray hit me in the face. About an hour later, the trouble came when I went back amidships to sit down on the deck. Then the effects of the spicy meal and ice cream hit along with the first signs of queasiness. Someone told me not to look at the horizon, but to look only at the deck to stall off the seasickness. I tried that, but the movement of shadows from the rigging moving back and forth on the deck finally did me in! I had no sea legs!<br />
It was a miserable couple more hours until we reached the smoother waters near the coast of the island. I was still a bit queasy as we made our approach, but all that ended when a minor disaster struck. The small boat ran aground! The boat's operator did not seem too concerned, saying we should just unload there. <br />
We all went over the side and found the water to be about neck deep. It was time to lower the equipment over the side and carefully carry it over our heads to shore. Somehow we got everything ashore with nothing getting wet, not even the logging paper!<br />
It was then that we got our first look at our operating situation. There was a small shelter made of driftwood already in place that provided a little shade. There were higher dunes about 100 feet back from the water line.<br />
The first order of business was to get the generator started and checked out. It was set up a hundred feet from the shelter to keep the noise down a little. The whole expedition almost became just a fishing trip at that point as the generator simply refused to start. Murphy's Law was in full force. The generator that had started many times on the first pull back up on the mountain was being cantankerous at sea level. <br />
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Mike and one of the fishermen did some kind of magic that also appeared to be some kicking, then playing with the carburetor that finally got it going. I am guessing that perhaps some adjustment on the engine to make it operate in the thin air on the mountain top might have been the problem.<br />
The next step was to get the antenna put up. That ended up being about a fifteen minute operation...just stacking the tubing for the vertical together, driving some stakes into the sand, standing it up and guying it off. Unfortunately, I have no pictures of the antenna, but there are some pictures of the antenna and the boat in either the July or August 1973 QST magazine DX column. <br />
The vertical was set up right at the water's edge with radials running off into the water. We did not have enough coax by just a few feet to have the antenna out in the water itself at low tide.<br />
It was now time to set up the gear. The operating tables were two portable tables that we set up under small shelter, running the coax out to the vertical and firing up. An end fed wire was strung from the shelter up to the small mast that we put on top of the nearest sand dune. It would be for our 80 meter link back to Asmara about 120 miles away. We tuned up one of the HW-101's into the wire first. There was no antenna tuner, one of the advantages of old school tube type radios. The Heath radios had a pretty wide range pi-network output circuit and we did not even worry about the match. The plate current dipped and loaded and that was that! Communications was established with ET3USF and our safety line was secured.<br />
The other HW-101 was loaded up into the vertical. It appeared to load up easily, without too many dips and loading adjustments. We were set to go, almost on our planned schedule. We had put out the word via the ARRL that we would be on the air by 1600 GMT. The delay at the harbor and the increased time to unload along with the problem with the generator had pushed us right up to that time with nothing to spare. Our local time was GMT plus three, so it was 1900 our time. <br />
<em> </em>I really don't remember if we had announced a frequency on which to look for us or not, but we found a clear spot below 14300 as I recall and put out a CQ, signing the callsign for the expedition, <br />
9F3USA/P1 (" Nine Fox Three Uniform Sierra Alpha Stroke Papa One" a real mouthful!) I don't know what we expected from that one short three-by-three call. Maybe we thought the world would fall in on us right away, so it was a disappointment when there was silence. It was the same after three such calls. Then Mike made a rather lengthy CQ call and unkeyed. After a short silence, a tentative call came back: I8HH. I remember that call well being the first that we worked. The exchange was a little longer than the usual expedition contact being the first and the fact that there was no crowd. I remember he repeated our call a few times, perhaps thinking it would attract attention to us. It did.<br />
When Mike cleared the contact, there were three stations calling. He worked those quickly, and then the roof fell in. The pileup was on. We worked a string of Europeans, then one JA who said he was going to announce our presence on a two meter repeater there in Tokyo. Things got really heavy after that with several pages of JA's worked in quick succession!<br />
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The pictures are a little faded with age, but here you see WA5TKC ( on the right) and myself (WA5IEX) on the left. The covers were off the '101's ( and us!). There was no concern about RFI or TVI out there and the temperature on the beach was about 130 degrees F. <br />
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There were no computers on this trip! All logging was by hand, with one operating, and the other logging most of the time. When one person alone was operating, it was quite a juggling act. Note the "small paperweight" used to hold down the log sheets in the sea breeze!<br />
Most of the operating was on twenty meters during the day. Forty meter operation at night was tough because we had no way to operate split and had to stay below 7100 because that was the top of the band for us. Than meant no US contacts on 40 meters, which left a lot of folks unhappy. A few did call us on CW on our operating frequency which was fine with us, but that apparently did not occur to many. While we had taken a key with us to operate CW, the QSO rate was so great on phone that we never got around to that. There was some fifteen meter operation Saturday afternoon.<br />
Twenty meters was open well into the night with hundreds of US stations worked. At one point the crowd got a bit boisterous and as we tried to work by call areas, folks were calling out of turn and it was getting impossible to pick out callsigns. At one point we got some great help from Bill, W2ONV who could hear us very well at his Saddlebrook, New Jersey QTH to try to calm the pile down a bit. The fact that we were running only 100 watts to a vertical made things a bit more difficult because the roaring hoard could not hear us under the thunder of the pileup when we tried to answer someone. It was incredible!<br />
The next day, about mid afternoon, something happened that I will never forget. We were working mostly African and Asian stations on 20 meters and in quick succession worked HS4, XW8 and A2C stations, then a few YU's. Callsigns were in the log that most of us would have lusted after at our home QTH's. A few minutes later the XW8 called again to say we were still very strong there and that " it must be nice to have an exotic callsign like that"! Whoa!!!<br />
That Saturday and Sunday morning were a blur. Again, compared to the big DX-peditions of today it was really small potatoes but it was a real trip for us. Sunday was packout day for the return trip. Because of security concerns and our military curfews for being on the road, we had to be back on the mountaintop before dark Sunday. Travel on roads outside the city after dark was prohibited.<br />
The trip back up the mountain was something. It was hard to believe that it had come and gone. The biggest thought was how we would ever top this later in our ham careers. This fear was pretty much allayed the very next time we were on the air from the club station and the pileup on the ET3 callsign was still heavy by anyone's standards.<br />
The one disappointing thing was that the trip did not count as a separate country. The IOTA or Islands on the Air program was either in its infancy or not begun at the time. But still, it was quite something to hear and HS4 and XW8 calling us at the same time! <br />
There had been no major problems after the early problem with getting the generator started. Oil consumption was a little high and we went through our spare cans, but the boat captain leant us enough to keep the generator going through Sunday morning. We ran out of beer Saturday about midday. But the fresh fish cooked on the beach over driftwood was fabulous. And if it got too hot behind the radios it was just a quick run across " hot sand, hot sand " for a dip in the Red Sea to cool off. What more could you ask for??<br />
But if there were fears that this little experience would leave us jaded to any "ordinary"activity in the future have proven groundless. There is still the same thrill of working a new one today, the adrenalin still pumps during the CQWW DX Test and there is still the same thrill at hearing a JA on 80 or 160 meters as the first time. <br />
If nothing else, the experience gives some appreciation for those who go on the truly difficult trips, spending thousands of dollars to put some rare spot on the air. The thought that what they are doing is many multiples of what we went through that time brings that about. It also brings some appreciation for what folks on the other end of the pileups go through. DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-61703443581868500452016-01-03T15:33:00.000-06:002016-01-03T15:33:05.489-06:00The Loop Project I have mentioned the use of loops in the past under the heading " Loop the Loop". This past week in one of my Facebook Groups there was a question about Low Frequency Reception and the use of loops. I posted a picture of a loop my father and I built and since there was considerable interest in the group I thought I would put the information here.<br />
This loop was build back in 1990 and has seen considerable use. It is a box loop or some would call a solenoid loop that is three feet across and tuned with a three gang variable capacitor. It tunes form roughly 180 to 1500 kHz. By tapping the coil and selecting one, two or three gangs of the capacitor, the tuning range can be varied.<br />
A tuned loop is actually a very simple device, with the difficulties being not in the electrical design but in the mechanics. This loop was made of wood and designed to be rotated in azimuth and tilted in elevation.<br />
To keep the loop from tilting over, my father who worked with me on the project, made the base from a salvaged solid core door. Now it must be mentioned that this loop is not small and is not light. The base must be heavy to make sure the loop is stable and will not fall over or try to move when its turned or tilted.<br />
The basic idea of any tuned loop is that it consists of a parallel tuned circuit. The loop is actually the coil part of an L-C circuit. It resonates at the frequency for which it is being used. A variable capacitor connected across the winding takes care of that chore. The one thing that is important if deep and clean nulls are to be obtained is that all connections should be very short. For that reason, we chose to mount the variable capacitor right in the center of the loop itself. This is not a remotely tuned device ( one must often chose between convenience and performance!!) It should be noted that no other connection is made to this parallel tuned circuit. It stands completely alone.<br />
The connection to the receiver is made through a two turn link wound a couple inches away from the main winding and connected to a short piece of coaxial cable that then runs to the receiver. A simple loop could be made simply by winding wire around a cardboard box or a plastic trash can and connecting the capacitor across the main winding and the link winding to the receiver. I have used similar arrangements many times, but this project came about with a desire to have something permanent and nice looking.<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="height: 859px; margin-left: auto; margin-right: auto; text-align: center; width: 653px;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjJ5MfWa0tK2iENaMxOlbynMhz0rxsc6HsH38Z9QdODPTBgZaXzrcbpE59ynR0rvWTG6AXrlPZVtH335P2DLMGpYrvmVAy4MQN3D6Ud3BtEgJqsBG3RgNZgQ75h19l0S-g2CfGHfkBMSpjk/s1600/loop+general.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjJ5MfWa0tK2iENaMxOlbynMhz0rxsc6HsH38Z9QdODPTBgZaXzrcbpE59ynR0rvWTG6AXrlPZVtH335P2DLMGpYrvmVAy4MQN3D6Ud3BtEgJqsBG3RgNZgQ75h19l0S-g2CfGHfkBMSpjk/s1600/loop+general.png" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">This is the loop sitting on a table in the back yard of my home. The cross arms are three feet in length, with wooden plates on the ends that support the windings. Additional wood pieces around the edges prevent the tension of the wire windings from puling the loop out of shape. This was a feature that was added after that problem showed up and resulted in an almost complete redesign of the antenna!<br />
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This view shows the mounting of the variable capacitor in the center of the loop. An alligator clip allows connection to one, two or three gangs of the capacitor as needed to change the tuning range.<br />
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This view shows the windings...In this case there are thirteen turns on the loop. They are spaced about a quarter inch apart. The two turn link is to the right.</div>
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Another view of the loop in my back yard looking toward the house and showing the tuning capacitor.</div>
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Another view of the loop with my forty foot vertical in the background. This loop is a little large for permanent use in the house at my location, so I generally use it when operating out in the yard at this table or portable at other locations. I have used it with a Radio Shack DX-440, My Icom R-75, Hallicrafters SX-96 and my MacKay low frequency radio. I do not seem to need a preamp with it. I have used it portable at Galveston and at various locations in the Texas Hill Country, usually just trying to find an electrically quiet spot. It has brought in NDB's from all over the United States and Canada, several from Cuba, ZBB from Bimini, many from Mexico and Central America and even some from South America, best NDB DX being from Ecuador. I have also received broadcast stations from Europe and Morocco while visiting at Galveston. I have found that the ability to null interfering stations to allow many stations otherwise unloggable being captured. It also helps in nulling noise. The lobes are much broader than the nulls, which are very sharp and deep, I can totally eliminate local broadcast stations with it. Tilting the loop in the elevation plane can also allow reception of stations at different distances in the same azimuth direction. Tuning of the loop is very sharp, especially on the lower frequencies.</div>
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DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-50028863027287345182015-12-16T20:54:00.000-06:002015-12-16T20:54:20.320-06:00My First Shortwave Receiver Everyone will always remember the first receiver that took them into the shortwave bands. I found mine in storage at my folk's house this week, retrieved it and brought it home. I thought it would be interesting to share what got me started.<br />
It was a homebrew receiver built from parts that had been part of lab experiments that came with a radio-tv repair correspondence course that my father had taken in the early 1950's. It was, in fact, watching him solder and work on assignments that first stirred my interest in radio.<br />
After he completed the course, the materials, including parts and printed lessons were stored away in a closet and when he figured I was old enough to know what to do with them, I was given the boxes of goodies. I was eleven years old at the time and already DX-ing with table radios and had begun poking around in them, trying to improve performance and hoping to get something going that would tune the short wave bands.<br />
Among the boxes of parts and papers there were chassis with holes punched and chapters on designs for various circuits used in superhet receivers. It was a matter of putting the pieces together to get the receiver transferred from sections of lessons to being an operating radio. There was one experiment that detailed making an H.F Converter to tune from about 6-18 MHz that would convert those signals to be tuned in by a regular broadcast receiver tuned to just above the high end of the broadcast band. That design became the front end of my first receiver to tune higher than the 160 meter amateur band ( I had previously gotten a standard broadcast receiver to go that high by pulling out the tuning slugs and loosening the trimmer capacitors as far as they would go).<br />
With the help of the head tech and owner of Lawson's Radio and TV repair shop I managed to get the thing assembled and working. I am not sure how many times I had the chassis in the basket of my bicycle for the two mile ride from our house to his shop, but with his help and parts from his parts stash and junk box, the radio became a working reality.<br />
The basic radio was a six tube superhet that tuned the broadcast band with one RF stage and one IF stage. It had an AC/DC power supply with a double section capacitor and choke filter. The RF stage was modified with a double tuned input aligned to 1650 kHz with another fixed tuned circuit on its output. The HF converter consisted of a 12K8 pentagrid converter circuit with its own filament transformer supply that lifted B+ voltage from the basic radio. The converter had its own two gang variable capacitor with the original radio set up fix-tuned to 1650 kHz.<br />
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<tr><td class="tr-caption" style="text-align: center;">Front and top view of the chassis of the receiver. The main broadcast band tuning capacitor is behind the large drum to the left with the HF converter variable capacitor that provided tuning for the short wave range is on the right. other controls volume, tone and power on-off switch.<br />
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Top view of receiver chassis At top left is the edgewise S-meter. This was actually a milliammeter reading plate current of the 455 kHz IF amplifier stage. The stronger the signal, the greater AGC voltage applied to the stage and resulting in lower plate current for the 12SK7 IF amplifier tube. Thus the S-meter actually read backwards. The stronger the signal, the lower the plate current indication. To make the meter read correctly, it was simply mounted upside down! The glass tube to the upper right is the 35L6 audio output tube. The metal tube to the upper left is the 12SQ7 triode-dual diode tube that served as detector, agc and first AF amplifier. The glass tube at mid rear of the chassis is the 12SK7 455 kHz amplifier. The metal tube behind the upper variable capacitor is the 12SA7 Second converter stage. The metal tube below the upper variable capacitor is the 12SK7 RF amplifier for the original BCB set redesigned with fixed coil tuning that became the 1650 khz IF amplifier stage. The glass tube at the rear of the main chassis is the 35Z4 rectifier tube. The metal tube with the grid cap connection above the lower variable capacitor is the 12K8 first converter. The lower variable capacitor tuned the HF converter and was the one used for selecting the shortwave frequency desired.<br />
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<tr><td class="tr-caption" style="text-align: center;">Under chassis wiring of the receiver. The HF converter chassis is to the left.<br />
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Close detail of the upper part of the HF converter stage showing the 12K8 Pentagrid Converter tube, the variable capacitor and the input tuning coil.<br />
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Closer top view showing the chassis top near the tuning capacitor for the base BCB portion of the receiver. The coil to the left of the larger variable capacitor is part of the fix-tuned 1650 khz IF circuit. The two silver cans are the electrolytic power supply filters. The clips on the rear of the chassis are the connections for antenna and ground. The small transformer on the rear of the HF converter chassis is for filament voltage for the 12K8 converter stage. The other six filaments are in series and operate like a conventional AC/DC receiver.</div>
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<tr><td class="tr-caption" style="text-align: center;">Under chassis detail of the HF Converter stage. The large coil is the oscillator coil for the 12K8 pentagrid converter. The small coil to the upper left is one of three tuned circuits between the converter and the rest of the receiver tuned to 1650 khz.</td></tr>
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<tr><td class="tr-caption" style="text-align: center;">Detail of IF amplifier stage showing the home made IF transformers. Windings were taken from discarded IF transformer cans, slipped over wood dowels and mounted horizontally to allow them to be placed farther apart than originally made to provide looser coupling in an attempt to get better selectivity. Fixed regeneration was also introduced into the stage to improve selectivity of the stage. Tuning was accomplished with mica trimmer capacitors below the coil and reachable by screwdriver through holes in the chassis from below.<br />
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The receiver was not the highest performing beast on the planet, but it did provide me with a method of listening in on the hitherto un available shortwave frequencies. It served for about three years as a way to explore my new world. I learned a lot about receivers from the project. In later years, I learned a lot that could have been done to improve it, including such things as converting the AC/DC supply to a transformer supply, which would have required another small chassis to handled the transformer. Voltage regulation could have improved stability. A manually tuned preselector could have eliminated the aggravating images that appeared on some places on the dial. The addition of a 1650 khz crystal between the two tuned circuits between the converter and the rest of the receiver could have greatly improved selectivity. The addition of a beat frequency oscillator could have improved cw reception that was obtained in the original by simply increasing the IF regeneration until the 455 khz stage went into oscillation. And a Q-multiplier added to the 455 khz IF could have finished the job of making the tuning really sharp. But that is probably just day dreaming " what-if's"...though to this day I wonder how it would have turned out had I known that at the time and actually made it happen. In any event, this receiver which probably looks a little crude to most was the source of many great hours of listening and adventures in the wilds of the short waves.<br />
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DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-56557019121292265702015-12-16T08:07:00.000-06:002015-12-16T08:07:27.847-06:00Is the Band really Dead? Ten Meter Test and More I hope this edition will not be two disjointed because it will cover multiple points, but at least as I begin to write, they are all connected.<br />
This past weekend was the ARRL Ten Meter DX Contest. This is not one of the " Biggies" but is one that is usually lots of fun and almost always provides some surprises. it is also a good one for SWL's because it is both phone and CW on the same weekend, meaning all can tune in and experience some of the same prop( any many of the same stations) whether they copy CW or not.<br />
For hams, having both modes on the same weekend gives activity even when the band appears to be " worked out", because when one starts running into the same stations with no new ones, one can just go to the other mode. Its also fun to run into the same station or ops on both modes because all of the other guys are doing the same thing.<br />
Which leads me to the question in this edition's title: " Is band really dead?" I never cease to be amazed by ten, and to a lesser extent, six meters. I so often hear or read on internet posts that the bands are dead and that there is nothing to hear, but upon tuning slowly and carefully, often find there is something there. There are times on ten meters particularly that when I hear no activity from operators, I can tune up into the " beacon band" ( roughly 28180-28300) I can hear the QRP beacons identifying their little heads off. The band is open, just nobody's home.<br />
Sometimes I think for hams, the band being dead becomes a self fulfilling prophecy as a result of folks expecting the band to be dead and not even checking it. Also, even if the band is inactive but open for the beacons, nobody finds anybody because all are just listening. This is one time that the idea of " listen, listen, listen and THEN call" should be abandoned, When the beacons are in and the background noise is up a bit, then is the time to call CQ, not just once, but several times. It might also be a time to self post one's self on DX Summit to try to attract attention ( though some might discourage self posting this might be an exception) If not wanting to post yourself, at least pot beacons being heard. Either might attract other folks, maybe even DX, to the band.<br />
In either event, it was with a little trepidation that I tuned up on the band Saturday morning. But I should have known that there is nothing better to open a "dead" band than a good contest. At 1352 GMT ( 0752 local CST) I immediately ran into HT7C coming into Central Texas at 28019.3 from Nicaragua with a pretty good signal. Only minutes later, a Special Event station from Chile was in at 28005.5 XR90IARU. The morning was filled with logging Central and South American stations. Interestingly, North American stations were absent. I could hear the South Americans working them, but they were for the most part inaudible here in Waco. I did hear K5NA, but that signal was obviously coming in via backscatter. One European, YT9X from Serbia, propped in at 1444 GMT.<br />
About midday, things got a bit more interesting. Stations from Eastern Canada began to come in, but the band also opened to the Pacific. Beginning shortly before noon, several Hawaiians were heard along with the catch of the day, 5W1SA from Somoa who was audible most of the afternoon with signals ranging from S-5 to S-9. No Australians were heard but did hear ZM1A from New Zealand on 28040 at 2227 with a signal just above the noise. About 2315 ( 1715 Local CST) the band snapped shut like the slamming of a door.<br />
Sunday was almost a repeat, with the exception that by mid morning many US stations were heard. By noon, a few African stations were coming in, including 6W1SR from Senegal at 1846. A couple South Africans were heard. I am not sure if the band was not open or this particular contest just did not attract that much attention from the continent. I heard US stations working Europeans but heard few myself. Once again, there were numerous Hawaiians coming in. By noon, the Northeast US stations were booming in with amazing signals, quite unlike the day before. Many pushed the S-meter will above S-9.<br />
All in all, a band that was supposed to be dead was simply unoccupied until the contesters showed up. I think many times hams, who as a group should know better, don't check the higher bands because they might take a look at some of the Facebook pages and see postings of "bands terrible" and don't turn on the radio. Some may even fall into the trap of thinking that we are on the down side of the sunspot cycle and the bands are expected to be bad. Sometimes even DX Summit can give one the feeling that nobody's home. But if we all do that, nobody will really know that the ionosphere is there waiting to be used! Besides, someone has the be the first to post something to SX Summit!!<br />
The same goes for SWL-ing. I have really enjoyed the Facebook groups I have discovered in recent days. They members are fun, they are sharing the love of the hobby with several diverse interests showing up. With members in different parts of the globe, it is particularly interesting to read about prop from " the other end of the path."<br />
But often, I will notice posts of " band dead, hearing nothing," or that one of the usual strong band occupants of 31 meters or some other band is not there. You can almost hear the disappointment and the feeling is that the poster will go off and do something else, perhaps missing a real nugget!<br />
There are times when some of the semi-local stations like Radio Havana, WRMI, WBCQ and others may be weak, fluttery, or almost non-existent. But then is not the time to turn off the radio and turn on the TV! Before doing that, it is a good thing to check around and see what else is going on down " in the weeds". <br />
When I see that posted on the groups, the first thing I do is go check the WWV frequencies. If on 10 and 15 MHz WWV is weak but WWVH is strong or even covering it, the band is far from dead...just open really, really long! Then is the time to turn on the BFO and start trolling 31 meters for carriers, then when one is spotted, go back to the AM mode and try to pull something out. Chances are, down in the grass will be a fluttery signal that will have the S-meter dancing a bouncy dance or maybe not even moving. There those of us in North America will find regional Chinese stations, All India Radio long path, Vietnamese stations, maybe even some of the big boys broadcasting to somewhere other than North America. If a semi local station is weak and fluttery or marked with echo, chances are you are hearing it back scatter or multi path. That is not the time to turn the radio off, but instead time to fill the coffee cup ( or other drink glass!) and pull on the headphones and pull out some new ones!<br />
If the upper bands are not showing much, keep dropping down to lower and lower bands until you find something. I usually start the evening with a sweep of the WWV and CHU frequencies and end up with a de-facto prop chart in the log. A look at the signal strengths for WWV, WWVH and CHU on 2.5, 5, 10, 15, 20 and 25 MHz and 3.33, 7.68 and 14.67 MHz respectively gives a pretty good picture of what is happening on the bands. Then I start with the higher bands and work my way down until I start finding the goodies. Sometimes a weak signal from WWV does not indicate a dead band, but one that has its legs stretched out long. ( at least for here in Texas...at your location, things might be different but you can learn over time what it all means)<br />
One of the other things I have noticed in the Facebook groups, particularly among relative newcomers to the hobby, its the notion that a simple short piece of wire thrown up along a fence or around a room is adequate for listening. In a way that is true, at least for casual listening to the power house stations targeting your listening area. Others in the groups will post suggestions that such is all they need, and that is true up to a point. <br />
However, I think this leads to some of the disappointed postings about the bands being in poor shape. If signals are just a few DB above the local noise level, if the bands take a shift, those signals might drop below the threshold of what that indoor or low horizontal wire might be able to deliver above the local noise. Or, a low horizontal antenna might not respond to DX signals arriving at a low vertical angle. For the new guys, I would suggest that that for beginning, those kinds of antennas are good for getting your feet wet, but nothing beats a good outdoor antenna at a decent height. Old CB antennas can deliver pretty good signals from stations pushing over a million watts of effective radiated power toward you, but won't do much for hearing a 10 kw station from Africa or Asia if you are in the US. The problem is not sensitivity of the radios, with many of the new ones having really good sensitivity. Its the ratio of the desired signal to the noise. Getting your antenna away from the noise and having enough up there to have a decent amount of voltage induced in it by a passing signal is the true answer. <br />
And the oft forgotten part is the all critical angle of radiation. A low, horizontal antenna will respond most to signals arriving at a high angle. Some low angle signals will be heard, but there will be a much weaker voltage induced by that passing signal. Horizontal antennas higher off the ground will respond to lower and lower angle arriving signals. A wire in the clear and not running though tree limbs or foliage will do much better. Wires running through trees also suffer the danger of having noise picked up by the trees that may be near power lines with other parts of their canopies. <br />
Vertical antennas or inverted L's will also do much better with the low angle arriving signals. The ionosphere acts according to the same laws of physics as does a mirror. The angle of reflection equals the angle of incidence. Signals from a greater distance arrive at a much lower angle than nearby signals. <br />
Often when a given band is just about to close, the effective height of the ionosphere is the greatest, meaning that signals from a greater distance will be coming in. This means that being there for the opening and the closing of a band might be the best time for getting the real DX!<br />
Speaking of the web, Facebook groups and other things, a big thank you goes out to Bob Padula in Australia for accepting my article on receivers used through the years and posting it on his excellent site The Mount Evelyn DX Report at medxr.BlogSpot.com.au I think I have links he posted there for many of you finding this site. The increasing number of DX groups brings a new aspect to the hobby, including the sharing of what is going on in real time. <br />
As always, I welcome comments and other ideas for articles and even DX tips. <br />
73 and good DX!<br />
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DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com2tag:blogger.com,1999:blog-1544382238317398005.post-35268910021462677802015-11-30T07:51:00.000-06:002015-11-30T07:55:52.516-06:00CQ Worldwide DX Contest 2015 Well this year's CW Worldwide DX CW Contest has come and gone. Thousands probably slept the sleep of the dead after being deprived of rest over the 48-hour contest period, eyes bloodshot from staring at receiver dials, stomachs aching from the acid of too much coffee and loads of snacks eaten in lieu of taking time for full meals and the ionosphere healing itself after being assaulted and heated by many times its usual portion of RF launched from backyards around the world. Ears are sore from headphones being pushed tightly over ears as if that would help a weak signal to be heard and foreheads may be raw from being held down on operating desks as if the operators could somehow concentrate more deeply on pulling callsigns out of the noise in an attempt to use sheer willpower to pull a signal up just one more db. Muscles are sore from tightening as keyboards were tapped or keying paddles swung as if that extra effort would add to the strength of the RF to push signals through massive pileups. Fingers are raw from keying with writing fingers on those of us who still use pen and scratch paper to write down tentative callsign identifications now having a callous not seen since high school days of writing term papers before computers.<br />
The CQWW is a massive collective effort to heat the ionosphere and get as many callsigns, zones and DX entities in a log in one weekend as possible. For many, it also involved the usual preparation of checking antennas, maybe putting up "temporary" antennas with wives assured they would come down and return the yard to its previous uncluttered state " after the contest" with the operator hoping he could stretch that long enough so the temporary structure would be considered part of the " new normal". For still others, it had meant months of planning trips to isolated areas to become the sought one in the bottom of those massive pileups.<br />
For some of us who would spend the weekend listening in the SWL mode without being able or desiring to transmit it would mean many of these same things, with the concentration just on listening. For all, there is the hope of logging all 40 zones, hundreds of countries and running up a score in the millions, with the secret hope that in addition to the glory of the weekend, perhaps a few missing entities would be added to the total overall country list, or at the very least, to the list of countries for a given band.<br />
The weekend was marked with particularly good prop with low noise on the lower bands, at least here in Texas. Friday night saw the high bands hot for the first hour, with DX being logged here from the Pacific on both ten and fifteen meters. The promise was short lived, however, as both bands folded up like a cheap tent the first hour, with 20 meters starting to fail shortly thereafter.<br />
Any frowns of disappointment were wiped out, however, by phenomenal conditions on forty meters. Listening in the search mode starting at the bottom of the band turned up great signals from Europe and the Middle East early, many pushing through the big gun US East Coast stations at the bottom of the band, leading to it taking well over an hour to get above the bottom 25 kHz of the band logging many great catches. Signals extended above 7100. After that, 80 meters was just as good, as any left over absorption in the D layer of the ionosphere faded away allowing even Mid East signals to come through with the energy often reserved for 10 or 15 meters. I ended up spending so much time on 40 and 80 that by the time I got down to 160 meters, the sun was already rising in Europe and I perhaps missed some opportunities.<br />
After a two and a half hour nap, I got back in front of the dials Saturday morning Texas Time checking the low bands for Pacific and Asia signals and they were there in force. Interestingly, some Asian stations were logged only on 80 or 40 for the weekend. The one disappointment was no Australian signals on 80 meters. Signals from both East and West Malaysia were logged on 40, with some Asian signals coming in as late as 9 AM local time with the sun well up.<br />
When the last of the JA's had dropped to the noise level on 40, a check of the upper bands showed ten meters already hot to Europe. Like the low bands the night before, the signals just kept pouring in, with the band being refused to be " worked out" until well after noon. Signals of unbelievable signal strength from Europe, Western Asia and Africa pushed the S meters of the FT-757GX, Icom R-75 and the venerable Drake 2B I used for the weekend well above S-9. In fact, by the time ten began to yield few new callsigns, 15 and 20 had shifted away from Europe and to South America and the Pacific. It would mean a shift in strategy for the next morning to start with 15 and 20 after the low bands folded to get the needed Europeans on those two bands.<br />
Saturday night turned out not to be a repeat of Friday night on the low bands, with 40 and 80 not being nearly as hot and 160 disappointing without a lot of good copyable European signals.<br />
All in all, from an SWL standpoint it was a highly successful weekend., with two new overall countries being added to the master " heard " list and several new band-countries added on 40 and 80. The big thrill of the weekend came with the logging of A52R from Bhutan on 15 meters about 2100 GMT Sunday. There is always something special about hearing signals from that part of the world that gives one a sense of wonder and mental pictures of the exotic.<br />
This was a weekend not for the faint of heart or those turning on the radio for listening to programs. It is a weekend for digging in the dirt of noise and pushing through the crowds to pull out a new one, or to log DX from JA and other entities until the log is gorged. It is a weekend for those who know how to copy CW to put things into the log that those who listen to broadcasts can but hope and dream about. It is about a shameless wallowing in a veritable sea of DX, picking them off in a target rich environment. It is a weekend with so much over indulgence in RF that one will almost not want to turn on the radio for days.Well, almost.<br />
For me, it means being very pleased with a special new vertical antenna put up " just for the weekend" that got an extra good ground from a weekend of rain that provided the grounding without lightning and static. The vertical provided the great loggings on 40 and 20 meters, being 5/8's wave high on 20 and just a little too long for 40, but nothing the Dentron Super Super tuner could not handled matching. The slopers and ground planes provided the RF for the receivers on 160,80, 15 and 10 meters.<br />
Stats are still being worked out, but initially it looks like over 1500 stations logged in 127 countries ( or "DX entities" for the purists) and 37 zones. Well, I did my best to create an RF "low pressure zone" in the neighborhood by pulling in as much RF as possible to protect the neighbors from the excess RF being launched into the air by all those amateur stations transmitting over the weekend.<br />
Was the indulgence in one of the primo DX contests of the year enough to assuage the appetite for DX and playing with the radios for at least awhile? I guess so. But then there are a few DXpeditions planned for the holidays coming up, there is the new schedule of broadcast stations to check out. And there is the 160 meter contest next month and the ARRL DX contest early next year...<br />
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73 and good DX!!<br />
<br />
<div style="margin-bottom: 0in;">
DX entities logged with notations on which bands they were heard.</div>
<br />
<div style="margin-bottom: 0in;">
Japan 160, 80, 40,20, 15,10</div>
New Zealand 40, 15<br />
Madeira Island 10,20<br />
Canada 160,80.40,20,15,10<br />
Senegal 80,20,40<br />
Brazil 10,15,20,40<br />
Peru 10,20<br />
Uruguay 10, 15,20<br />
South Africa 10,15,20
<br />
Hungary 40,20,15,10<br />
Slovenia 80,40,20,15,10<br />
Canary Islands 80,40,20,15,10<br />
Aruba 160,80,40,20,15,10<br />
Spain 80,40,20,15,10<br />
Germany 80,40,20,15,10<br />
Slovak Republic 80,40,20,15,10<br />
Russia ( European) 40,20,15,10<br />
Azores Islands 40,15<br />
Moldova 40<br />
France 80,40,20,15,10<br />
Cyprus 40,20<br />
Czech Republic 80,40,20,15,10<br />
Belgium 40,20<br />
Scotland 40,20<br />
Ireland 20<br />
Poland 80,40,20<br />
Serbia 80,40,20<br />
Bulgaria 40, 20<br />
Switzerland 80,40,20
<br />
Cuba 80,40,20,15,10<br />
Albania 15, 40<br />
Italy 80,40,20,15,10
<br />
Wales 40<br />
Iceland 15, 20<br />
Croatia 80,40,20,15<br />
Morocco 10, 40<br />
Gibralter 40<br />
England 80,40,20,15,10
<br />
Corsica 80, 10<br />
Montenegro 20, 40<br />
Greece 40<br />
Venezuela 20, 15<br />
Hawaii 160, 80,40, 20, 15, 10<br />
Puerto Rico 40,20,15,10<br />
Curacao 160, 80,40,20,15,10<br />
Sweden 15, 20, 80<br />
Netherlands 80, 40, 20<br />
Dominican Republic 80,15,10<br />
Shetland Islands 40<br />
Portugal 10,20,80<br />
Bonaire 160,80,40,20,15,10<br />
Mexico 160,80,40,20,15,10<br />
Marianas Islands 80, 15
<br />
Philippines 80<br />
Asiatic Russia 80,40,20,15,10<br />
China 80,40,20
<br />
Hong Kong 40,20<br />
Kazakhstan 40<br />
Vietnam 40<br />
Thailand 40,20<br />
Georgia 40<br />
East Malaysia 40<br />
West Malaysia 40<br />
Colombia 10<br />
Mozambique 15<br />
Cayman Islands 15, 20<br />
Martinique 10,15,20<br />
Cape Verde 20,15,10<br />
Madagascar 15,10<br />
Barbados 10<br />
Finland 10,15,20<br />
Argentina 10,15,20
<br />
Belize 20,15,10<br />
Suriname 10,15<br />
Zambia 10<br />
Costa Rica 10, 15<br />
Chile 10<br />
Ascension Island 10, 15, 20<br />
Rodriguez Island 15<br />
Virgin Islands 15<br />
Australia 15, 20, 40<br />
Guadalupe Island 15, 20<br />
Anguilla 15<br />
French Polynesia 15<br />
Trinidad 15<br />
Honduras 15<br />
Aland Island 20<br />
Alaska 20,15<br />
Fiji 15<br />
Guam 15,20<br />
French Guiana 20<br />
Maldives 20<br />
Norway 20<br />
Bahamas 20, 80<br />
Bermuda 160, 20<br />
Turks and Caicos 15<br />
Svalbard 20<br />
San Andres 20<br />
Antarctica 20<br />
Oman 20<br />
Qatar 20<br />
Micronesia 80<br />
South Korea 80<br />
Romania 20<br />
Ukraine 20<br />
Denmark 20<br />
Lithuania 20<br />
Jordan 20<br />
Israel 20<br />
Latvia 20<br />
Bosnia 20<br />
Kuwait 20<br />
Belarus 15<br />
Grenada 15<br />
Northern Ireland 15<br />
Estonia 15<br />
Luxembourg 15<br />
Paraguay 15<br />
Rwanda 15
<br />
Nicaragua 10<br />
Saba & St Eustatius 10<br />
Easter Island 15<br />
St Lucia 15<br />
St Kitts 10
<br />
Saudi Arabia 20<br />
Greenland 15
<br />
Bhutan 15<br />
<br />
<div style="margin-bottom: 0in;">
<br /></div>
DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-85511589139797630032015-11-26T10:22:00.003-06:002015-11-26T10:22:47.614-06:00A First Big Antenna Project Adventure
<br />
<div style="margin-bottom: 0in;">
Everyone has had their
first “ big antenna project.” Some are carefully planned out,
some are haphazard and some turn into great adventures. My first
“B.A P” came when I was thirteen years old. I had been a
shortwave listener for a few years, had obtained my Novice Amateur
Radio License and had taken my General Class exam and passed.</div>
<br />
<div style="margin-bottom: 0in;">
While waiting for the General
Class License to appear, I began thinking about new antenna
possibilities. The antennnas up in our yard consisted of two
longwires suspended between twenty-foot-high masts made of 2X4's. The
wires were seventy feet long and supported by three foot long
hardwood spreaders, running parallel between the masts, one for
transmit and one for receive.
</div>
<br />
<div style="margin-bottom: 0in;">
I knew that the twin longwires I
had would work at least passibly. I had used them for shortwave
listening and had made numerous contacts in the Novice Bands,
including a fair amount of DX. But I had also been reading that
antennas needed to be up higher to get a lower angle of radiation.
At the same time I knew that my dad had mandated “ no guy wires in
the yard” and the yard had to be uncluttered.</div>
<br />
<div style="margin-bottom: 0in;">
A tower was out of the question
cost-wise. Masts would require guy wires. So what was I to do?</div>
<br />
<div style="margin-bottom: 0in;">
The answer came a few days later after
an accident down the street resulted in a utility pole being broken.
The Texas Power and Light Company crew came and replaced the pole,
but left the old one that had been broken off at ground level lying
in the ditch.</div>
<br />
<div style="margin-bottom: 0in;">
My dad and I got the idea about the
same time. If that pole were left lying there for very long, it
might just get a new home! After a week, he called a friend of his
with TP&L and asked if the pole was going to be picked up and he
was told they would when they could, but that if it were to
“disappear” it would save them the trouble of disposing of it.</div>
<br />
<div style="margin-bottom: 0in;">
The problem was getting it home. It
was about three or four blocks away down Harrison Street where we
lived at the time in a suburb on the east side of Waco in Central
Texas. My dad was not one to be deterred once he got an idea. It was
fairly late on a Monday night when he told me to get in the station
wagon and take a ride with him.</div>
<br />
<div style="margin-bottom: 0in;">
At that time he was driving a '57
Chevy station wagon for a work car. He loaded a long, heavy chain in
the back and off we went. He turned around in the street and backed
up to where the pole was in the ditch. The two of us managed to lift
one end of the pole off the ground and propped it up on a concrete
block he also had brought. He looped the chain around the pole a few
times and hooked the free end into a link. He then ran the other end
of the chain under the back of the station wagon and hooked it to the
frame of the car.
</div>
<br />
<div style="margin-bottom: 0in;">
My eyes were getting a little big
about this time. We were actually going to drag the thing home? At
10:30 at night, there was virtually no traffic on our semi-rural
street. He told me to ride in the back and watch to make sure nothing
was coming lose and he cranked up the Chevy and eased forward.
</div>
<br />
<div style="margin-bottom: 0in;">
The chain tightened and the loop
snugged up around the pole. There was much groaning and vibrating of
the chain as the load came on it. With great care and a little
slipping of the clutch he then slowly got the Chevy rolling with the
pole dragging behind us. He managed to get into second gear and we
were soon going up the street at about ten miles per hour with the
pole dragging behind us. Once or twice he had to slow down or stop
when the lower end of th4e pole started swaying back and forth across
the road a bit. The heavy end of the pole dragging on the street made
quite a noise and I could just imagine they residents of the street
coming out to see what was going on and maybe calling the police!
After what seemed like an eternity and much gnashing of teeth it
appeared we would make it to our house without incident. Luckily we
did not meet any cars coming toward us as my dad was driving in the
middle of the road, trying to keep the end of the pole from swinging
into a ditch or hanging on a culvert or mailbox. Somehow, things
went ok and we got home without a crash..
</div>
<br />
<div style="margin-bottom: 0in;">
Instead of pulling into the drive, he
parked alongside the yard on the street and got a dolly and a
</div>
<br />
<div style="margin-bottom: 0in;">
small wagon. We unhooked the chain
and lifted the small end of the pole onto the wagon and tied it
firmly in place with a short piece of rope. He then got the dolly
under the large end and we began the slow process of getting the pole
off the street and into the back yard.</div>
<br />
<div style="margin-bottom: 0in;">
He already had in mind where he wanted
to put it in the back, right corner of the yard. It took a bit of
maneuvering to get the bottom or larger end of the pole into the
right spot. The pole did not want to stay in place on the wagon and
at one point during the turning and backing process we gave that up
and just lifted it by hand and moved it a foot or two at a time. ( it
was HEAVY!!) Sometimes it was more lift and roll than carry. There
was a lot of sliding and rolling of this thing because it was not
only heavy but over 40 feet long. We got it into the back yard
before we realized we had to reverse ends with it to get the large
end in the corner. That meant making a sharp bend to miss clothesline
poles and a fence. It was about an hour long job to get it in place.</div>
<br />
<div style="margin-bottom: 0in;">
We got it in place parallel to the
side fence with the bottom about ten feet from the back fence when it
occurred to me that I didn't know how we were going to get something
back there to dig the hole. My dad said we were going to have to dig
the hole by hand. He wanted about eight feet of the forty-five foot
long pole in the ground and it would be my job to do most of the
digging! If I wanted a DX Pole, I would have to do the work!</div>
<br />
<div style="margin-bottom: 0in;">
After all the work it took to get it
in place, I found myself full of doubts and questions. How would we
ever be able to lift the heavy pole into a vertical position when we
could barely move it into the back yard? How would we get a hole dug
for it when there was not a way to get a tractor with an auger into
the back yard? We certainly could not afford to pay anyone to do it!
Most importantly, how would I ever get any antennas on it after it
was up because there were no climbing steps on the pole. They had
apparently been removed by the power company after they cut it down.</div>
<br />
<div style="margin-bottom: 0in;">
As usual, my dad already had a plan.
He probably had it all worked out before we even drove down the
street to drag the thing home. He was a carpenter and had come from a
farm background and was expert at working out ways to do things in a
way that would substitute manual labor and ingenuity for expense in
getting a job done.
</div>
<br />
<div style="margin-bottom: 0in;">
The “manual labor” would be mine.
The ingenuity would be his.</div>
<br />
<div style="margin-bottom: 0in;">
I would dig the hole. We would start
with our regular manual post hole digger. This was basically a small
auger with a four foot stem and wooden handle. You made it work by
putting the auger end down and turning the handle round and round.
It would eventually “bite” into the ground but it required not
only turning, but downward pressure.</div>
<br />
<div style="margin-bottom: 0in;">
It would not dig a hole
nearly big enough around to accommodate the pole. It would cut a hole
only about ten inches in diameter and the bottom of the pole was was
almost two feet across. But my dad said that “would not be a
problem.” I would use a heavy chiseling pole and a sharpshooter
shovel to cave the sides in once the hole was started, then use the
post hole digger to haul out the lose dirt. I could see a lot of work
in my young future!</div>
<br />
<div style="margin-bottom: 0in;">
It was not long before I would learn
just how big a job this would be.. The first afternoon, I got the
hole down about three and a half feet. His plan worked well. Dig
down with the auger, pull out the loose dirt. Cave in the sides, dig
out the loose dirt. Then cave the sides in some more and lift out
the loose dirt. Repeat, repeat, repeat.</div>
<br />
<div style="margin-bottom: 0in;">
When he got home from work that next
day, my dad told me I needed to round out the hole even more to make
sure the pole would not only fit in it, but slide down without
problems. He also noted that the hole was not nearly deep enough,
even though at the depth it now was, the handles of the post hole
digger were just about scraping the ground. It turns out he already
had a plan for that.
</div>
<br />
<div style="margin-bottom: 0in;">
With a pipe wrench, he unscrewed the
handle off the pipe stem of the post hole digger and with a heavy
coupling, put a five foot extension of heavy duty water pipe on the
shaft and then screwed the handle back on the top of that. It would
mean I would have to stand on top of a small platform to be able to
turn it until the hole was deeper, but “ that should not be a
problem for you”.</div>
<br />
<div style="margin-bottom: 0in;">
The next morning I got up early and
started digging. It took all day of climbing on top of the platform,
dropping the post hole digger down into the hole, turning it until it
filled up, then lifting it out hand-over-hand to dump it out. Then
there was the caving off of the hole and removing the loose dirt. I
don't know how many times I actually dug and redug that hole before
it appeared to be ready!</div>
<br />
<div style="margin-bottom: 0in;">
But there was till the question of how
we were going to lift the pole and how I was going to get the
antennas on it. That question was partially answered when my dad got
home from work that day to inspect and pass on the hole.</div>
<br />
<div style="margin-bottom: 0in;">
He had brought with him a couple of
lengths of used water pipe salvaged off a remodel job he was working
on. He had somewhere obtained a couple dozen large, 18-inch long lag
bolts and rummaged through his massive collection of used hardware
and dug out a couple dozen large washers.</div>
<br />
<div style="margin-bottom: 0in;">
He figured that about nine inches of
lag bolt going into the side of the pole would be enough to support
our weight. My job for the next day would be to cut the water pipe
into six-inch-long pieces. The large washers would be put under the
heads of the lag bolts, the pipe slipped over the bolts to provide
foot rests and the lag bolts screwed into the side of the pole.
Instant climbers! Actual climbing steps such as appeared on regular
utility poles would have cost a small fortune. I am sure that even
the lag bolts were probably not cheap, but I am betting he bought
them at a used and salvaged materials store in town where he often
bought lumber for projects and I am sure he got a good deal on them!</div>
<br />
<div style="margin-bottom: 0in;">
He set me up with a pipe vise and a
couple of saw horses to use in cutting the pipe and left me with a
hack saw and some spare blades. The next day was spent cutting,
assembling and screwing the lag bolts into the pole at intervals of
about 18 inches.
</div>
<br />
<div style="margin-bottom: 0in;">
The attaching was not as easy as one
might imagine. I had to drill a small pilot hole to get started,
then get the large lag bolts screwed in. The wood in the pole was
creosote treated, aged and tough. Of course this was a good thing,
because it meant that the bolts would be well anchored and not be
liable to slip out or loosen when one's weight was applied. This
would be a good thing when one is over thirty feet in the air! There
was more than a little bruising of knuckles using a large crescent
wrench for the final tightening. The washers on the ends were to
provide a stop to prevent the climber's foot from slipping off the
ends of the climbers.</div>
<br />
<div style="margin-bottom: 0in;">
The question of raising the pole was
still open. That day after work my dad came home and we moved the
bottom of the pole away from the pole a couple of feet. This
confused me a moment until the shovels once again came out and we
began digging a small ditch just a bit bigger than the width of the
pole along its length. The ditch went from a depth of about 18
inches at the edge of the hole and sloped up to ground level over
about five feet. This resulted in a little loose dirt once again
falling into the hole and more digging of it out.</div>
<br />
<div style="margin-bottom: 0in;">
While I was doing this, my dad was
cutting up some two by fours and two by sixes of different lengths
and nailing them into “x” shapes of varying lengths. We got the
pole moved back over with the bottom extending over the top of the
hole and lying in the freshly dug ditch.</div>
<br />
<div style="margin-bottom: 0in;">
Part of the plan became evident in a
few minutes when one of my uncles and a neighbor showed up. We began
by lifting the small end of the pole up and slipping the smallest of
the “x's” under the end. The pole would be lifted a little and
the “x” scooted up a little more, raising the end of the pole
about a foot off the ground. Then a slightly larger “x” was
placed under the end and both scooted up. This continued until there
were four or five braces under the pole. Two ropes were tied to the
pole about two-thirds of the way up and a long heavy chain attached a
little higher.</div>
<br />
<div style="margin-bottom: 0in;">
My dad then cranked up his station
wagon and drove down to the neighbor's place whose field backed up to
our house. The houses on our street lay in a single line with a
large open field behind them all where the one neighbor ran cattle
and horses.
</div>
<br />
<div style="margin-bottom: 0in;">
My dad drove out into the field and
backed up to the fence. The plan soon became clear. The chain was
hooked to the frame of the car, my uncle and the neighbor got on the
ends of the two other ropes, stretching them out in opposite
directions at right angles to the pole. I was told to “ stay out of
the way”.</div>
<br />
<div style="margin-bottom: 0in;">
As he slowly began to drive forward,
the chain tightened. The pole began to lift. The bottom hit the back
of the hole and could not slide forward any more. The chain tightened
more and began to vibrate, the pole lifted and the x-braces fell
away. There was no turning back now. The two men on the ropes pulled
against one another keeping the pole straight while the lift-chain
stretched and creaked. The pole lifted to about 45 degrees, then
seemed not to want to go farther. My dad gunned the engine in the
station wagon, the rear wheels began to spin and for a moment I
thought it wasn't going to make it.</div>
<br />
<div style="margin-bottom: 0in;">
The pole moved up and as it came to
near vertical, the two men on the ropes both moved back toward the
house to pull against the rise a bit, I am assuming to keep it from
going over and falling onto the station wagon. The pole reached
vertical and stood there. It wiggled . It did not drop into the hole.
The neighbor and my uncle yanked on the ropes and my dad worked the
clutch in the station wagon, working the pole back and forth and
finally with a loud “thunk” it sank into the hole.</div>
<br />
<div style="margin-bottom: 0in;">
Never to leave anything to less than
perfection, my dad came back to supervise the filling in of the dirt,
holding a level to the pole in several places to make sure it was
plumb. Slight adjustments were made by filling in dirt more on one
side or the other and jamming the heavy chisel pole as a tamping tool
along the sides. Then as more dirt was filled in, the garden hose
was brought in and the hole was soaked while more tamping and filling
went on.</div>
<br />
<div style="margin-bottom: 0in;">
The tools were picked up, everything
cleaned up and the men took a Pearl Beer break. I even got a small
glass.</div>
<br />
<div style="margin-bottom: 0in;">
The directions for the next day were
to continue to soak the hole and as the dirt settled to tamp more on
top. No climbing was to be attempted for a week until everything
settled. The job was done in a way that I am sure some government
safety organization would have had a hissy fit over. ( OSHA did not
exist in those days!!)</div>
<br />
<div style="margin-bottom: 0in;">
The DX pole was up. The planning of
the first project for my expanding “antenna farm” was underway.</div>
<br />
<div style="margin-bottom: 0in;">
</div>
<br />
<div style="margin-bottom: 0in;">
</div>
<br />
<div style="margin-bottom: 0in;">
</div>
<br />
<div style="margin-bottom: 0in;">
<br />
</div>
DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-56434473146212138032015-11-19T06:22:00.001-06:002015-11-19T06:23:05.638-06:00DX-ing as a Magical Adventure Someone on one of the SWL Facebook groups of which I am a member said something in a post about one of his "adventures " being magical. It seems he had heard a station on his main rig, then listened to the same station on a portable while he worked doing something else. It seemed like magic to him. There followed several posts echoing that idea.<br />
That struck a strong chord with me because I have felt the same thing many times over the past fifty plus years of spinning the dials. Even before I began listening to weak signals through my own first crystal set going back to the times I, as a child, listened to kid's stories broadcast by one of our local stations back in the early fifties, adventure seemed to pour out of that small wood box with lights inside.<br />
There were radio dramas that let the story play out on the stage inside the mind. It was limitless. Whether it be The Lone Ranger, Rocky Jones, Space Cadet or even Little Orphan Annie. I still remember the children's stories broadcast by long defunct KMLW and the wonderful performance of Peter and the Wolf that first introduced me to classical music as a child. ( I still laugh when I see a bassoon!)<br />
The adventure changed somewhat when my dad was taking a radio-tv repair correspondence course. He built radios that brought in stations from all over. These were only AM broadcast stations at the time, but the idea of listening to The Grand Ol' Oprey via WSM in Nashville or The Louisiana Hayride from ( I believe) KWKH in Shreveport in our living room just outside Waco, Texas was amazing to the then seven year old.<br />
As I learned ( and was allowed) to turn the dials of our old standup Silvertone radio I was able to find music and programs that kept me busy on hot afternoons on our small farm. The radio transported me beyond the confines of that room. And I must admit, the sounds of that radio along with the drone of the big evaporative cooler that fought the Texas heat long before we could even dream of air conditioning often lulled me into sleep and real dreams, sometimes guided by what was on the radio.<br />
But most of all it was the sound of the distant stations brought in at night that really fired my imagination. Maybe it was the exotic sound of the selective fading. Sometimes there was a bit of angst as the station would fade and my dad would say,<br />
" Don't worry, it will fade back up. It will be back in a minute."<br />
A little later as I sat with my Bell headphones clamped tightly over my ears listening to the faint sounds coming from the Remco crystal set kit the hook was really and truly set. Those faint signals, particularly those I strained to hear after our local stations signed off at midnight, fired the imagination. Somehow, some way what was going on in that distant studio was leaping into the air, traveling miles and miles through the air and being snagged by the wire strung between the peak of the roof of our house to the tall water pipe mast my dad had erected at the back of our garden.<br />
When I would ask if we could get stronger signals or more distant stations, he would say we might if we added more wire. So we added more wire along the side of the house and further out beyond the garden to the chicken houses. We must have had over 250 feet of wire ranging from about 20 feet to maybe 35 feet high.<br />
While adding the wire seemed to aggravate the situation of making the local stations spread out on the dial of the crystal set, it did help the signals coming into the six tube radio he had built as a kit that came with his training course. And after the local stations signed off, when I would sneak the headphones onto my head in the midst of the night, there were more stations to be heard on my little Remco. The ones I remember were WOAI from San Antonio, KRLD and WFAA from Dallas and WBAP from Fort Worth. There were others I just don't remember and at seven or eight years old I had no concept of logging.<br />
Every time I would put on those headphones, the idea that sound was coming from them that was sent from some distant place was being transmitted to my ears was truly magic. Even if the stations were the same as the ones heard before, it was still the same.<br />
The level of magic increased over the years. First it was listening to my Watterson table radio that had belonged to my grandfather, hearing stations from Dallas, Houston or San Antonio. Then listening at night to signals from Chicago, St Louis, Cincinnati and various points in Mexico. Then came the shortwave days with the sounds of England, Spain, Switzerland, Ecuador, Australia.<br />
On a Facebook post in one of the groups made up of short wave listeners I have recently joined, someone noted that same thing. A distant station was heard on a receiver that was on an outdoor antenna that was later heard on a small portable while he was doing something around the house. He noted that it seemed magical that he could be hearing something from a distant land with no intervening wires. Others soon posted on the same entry of their similar feelings.<br />
What is it about radio that brings these feelings? Perhaps it is not just the radio itself, but something that still lives within some of us. A sense of wonder at something special, the ability to recognize and enjoy something for its own value, and somehow not become jaded to its reappearance over time.<br />
There are some in the amateur radio community who work DX and contests and such. I am among them. But some have approached the ham radio hobby, and perhaps the SWL hobby in a big rush and work or log countries in a hurry, win contests, collect QSL cards, trade equipment it seems every other week and burn out on it quickly, losing interest. <br />
Others seem to savor the experiences, listening for programs, studying the prop, finding things to tune for even when the bands are poor. I think perhaps there is a difference within people in how they react to experiences in general, not just the radio hobby, that has something to do with it. It is not a "competition" except perhaps with one's own skill level. It is an enjoyment of what is!<br />
There is nothing to match the thrill of being a kid and hearing Tokyo for the first time on 25 meters on a morning before school. The difference for some is that it is noted, then tossed aside with no interest in doing it again. But for some of us, every time that signal comes out of a speaker or headphones, some of that thrill comes rushing back.<br />
The same goes with working DX or hearing it on the ham bands. There are literally thousands and thousands of hams in Japan, but somehow hearing a JA or JH or JO station come back when my hand pulls back from the key never diminishes. Even just the idea of pulling a signal that someone launched into the air from their backyard with a small box in their home has never lost that shine.<br />
From the other side, I had a moment while working at my first radio station back in the 1960's. I had been playing records on the radio on a Saturday afternoon, answering the request line, "playing the hits" when I happened to turn and look out the back window of the control room and saw two of the four towers of the station's antenna array in a new light. What I was doing in that control room where the meters were dancing, the phone lights were flashing and Rock and Roll was coming out of the monitor speaker at a level that was probably near the pain threshold was being sent from that room into the transmitter room through the window to my left, the glowing tubes were generating the signal that was going to the towers outside, where it was leaping into space and reaching out to touch those very people who had been calling on the phone asking for their song. It was also reaching out and touching hundreds, perhaps thousands as far as 150 miles away. It was both a sobering and wonderful moment.<br />
Its something to think about when we spin the dials. There is indeed a magic in what we experience. Somewhere, in a distant place, what we are hearing is being created by someone in a studio or spoken into a microphone or keyed into a transmitter in a home somewhere. It is leaping into the air, flying through space, bouncing around and sweeping by our antenna leaving a little mark of its passage as it continues to fly yet farther. What could be more magical than that? <br />
No matter what the content of the program from a broadcast station or transmission from the radio amateur, the effect is the same. Something created in a distant land has come to us. Those who recognize it are blessed with a true experience. Those who note it and let it go miss part of it. <br />
There are other wonders that come along with our hobby. Someone else noted when commenting on a kit receiver someone had purchased and was enjoying that looking inside it was sort of like looking at the person who wired it. Listening to a song is like looking inside of the person who wrote it or sang it. Looking at a painting like looking into the soul of the artist. Reading a story or a poem is like hearing the thoughts of a writer.<br />
Perhaps all of this is not so much just about radio or cold, technical facts. The enjoyment of the hobby is just like the enjoyment folks get from actually " seeing" or "hearing" anything that goes on around us in the form of art or just life. Perhaps we should be thankful we were given the ability to see what others might just pass over.<br />
Perhaps a little philosophy has crept into what some would see as a cold, technical geeky hobby!<br />
Good DX and Happy Listening.DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-36715331067913855872015-11-15T11:36:00.001-06:002015-11-15T11:36:39.691-06:00Tuning Tricks, Antenna Trimmers and Observations This weekend ( November 14 and 15, 2015) has indeed been an adventuresome weekend on the radio. Three new band-countries jumped into the log. I call it a "band-country" when its a new country on a given band. In this case it was Willis Island as the current DX-pedition got underway and I managed to snag them on 12 and 10 meters for the first time, having logged them on 15 meters from an earlier trip to the small island. This is an example of how the only way to put a country into the log is via the amateur bands, because there is just nothing else there to generate a receivable RF signal! That takes my 12 meter total to 173 and my 10 meter total to 216.<br />
The other was Ascension Island heard for the first time on 80 meters, taking my 80 meter country total up to 118. I realize my total on that band is not that impressive compared to the " big guys" but given the size of my antennas and my relatively noisy location, I am happy with any new one I can get! Of course this did not add to the overall countries total because Ascension has been there for a long time thanks to much more powerful transmitters pushing out the BBC's signal!<br />
Overall it was a pretty good weekend to be listening. It was rainy most of Saturday and outdoor chores had to wait. The bands were fairly good. Friday night 40 meters was very good. While it was not a new country, it was a thrill to hear Kenya , Western Sahara and the Canary Islands on the ham bands between what was actually 0200 and 0300 Saturday the 14th.<br />
Earlier time in the evening was unfortunately spent in front of the television watching coverage of the tragedy in Paris. It also appeared that the BBC was quite strong in several spots, leading me to wonder if they did not lay on some additional transmitters and beam headings that favored the US for their coverage. Perhaps some of you who keep track of them more closely might add comments. I could post them later if you should notice such. International events often generate transmissions that are outside the norm.<br />
Saturday morning Texas time listening began about 1300 GMT. ( OK, so I slept in a bit!!) The initial WWV sweep showed it would be a good day. Beginning at 1348 GMT, the 2.5 MHz WWV was S-9 + 20 DB with WWVH from Hawaii just barely detectable in the background. The 5 MHz WWV was S-9+ 20DB with WWVH clearly audible behind. On 10 MHz WWV and WWVH were about equal strength with the S-meter at 20-over. On 15 Mhz surprisingly WWV was S-8 to S-9 but bouncing around a lot with no signs of WWVH. The best was yet to come!. Even this early with sun probably just rising at their transmitter site, WWV on 20 MHz was already up to S-5 and S-6 and was clearly audible on 25 MHz!<br />
I noticed when checking the amateur contest listings for the weekend that the OK/OM DX contest ( Czech Republic and Slovak Republic respectively) was going to be on CW and the JIDX ( Japanese) DX contest was going to be on phone. That would mean some possible DX targets two ways. One, it would be fun to see how many Czech and Slovak stations could be logged on CW and how many Japanese stations could be logged on phone on difficult bands. But also, these smaller contests are also ways to log other countries listening for stations calling those hosting the contests. The trick is often to listen at times when prop is NOT good to the host country and to listen for other DX stations calling THEM. The " trick" is to look for pileups or to look on one of the spotting websites like DX Summit and look for stations host country hams are posting that might have prop to you and go park on those frequencies.<br />
Of course for listeners within the host countries its an easier deal. Find a station in your country that is working a good run and park on that frequency and let them bring the DX to you!<br />
Or, if there is a relatively rare station working the contest in your continental area that those working the contest in the host country would probably like for a points multiplier, park on HIS frequency and let him attract the DX to you. This works particularly well on the " hard " bands for hearing the host country. For example, here in Texas listening on 160 or 80 meters if there is a Caribbean station working the contest parking on his frequency will increase your chances of hearing the host country's stations on a tough band.<br />
The same works for DX-peditions. For example, this weekend was VK9WA on Willis Island was working stations and telling them to call " up" or above their working frequency. By tuning off the expedition and into the " pileup zone" you will find lots of goodies to put into the log. It may take careful tuning and highly concentrated listening to pick callsigns out of the pile, but it can often be worth it. QSL's sought from these stations will be easy to get as well, because you can believe those operators will remember the time and place where they were trying to bag a good one!<br />
For those whose CW is just developing, listening like this is great practice. It always help in building speed to listen in deep concentration in tough conditions. Also, anyone can copy for short bursts at a much higher speed than their average copying speed. As in physical exercise, "stretching" always leads to improvement!<br />
This also applies to listening in pileups on phone, just in a different way. It will help develop your " DX-er's ears" by helping to develop the mental technique of pulling what you want out of apparent chaos through concentration. <br />
In both cases, phone and cw, it may take callsigns going by several times to allow you to pick them out. You will find yourself getting one letter at a time, until the entire callsign is filled in. I usually write them down on scratch paper and while digging in a pile, either add each new letter to those already written down, or drop down a line for each "listen", finding sometimes it may be required that a letter be changed because it was not heard properly the first time. For those familiar with mathematical terms, I guess you could say this is a form of " mental integration"!<br />
I have found that the same "mental integration" technique works in trying to identify a station down in the noise. Listening over and over and over will sometimes have the signal fade up and down or noise bursts be present or absent in different places to let the ID finally pulled out and another one in the log! <br />
Of course the old hands reading this will be saying " I knew that all along" but maybe trying some of these things will help the " newbies" learn a little faster, develop mental acuity and perhaps avoid frustration that might lead to ( "gasp!") dropping the hobby!<br />
These techniques can also be used for DX-ing other things than just the ham bands. Broadcast stations ID's or clues to identity can slip by quickly. For those who run audio recordings, often running them several times will allow some form of mental integration. For those with SDR's, the same might be the case, perhaps with different passband or selectivity settings. For those who take the hobby beyond just listening to programs this could lead to bagging a good one rather than letting it go by because copy is tough. ( not that just listening for programs is not a good thing, there are some great cultural things to be experienced listening to SWBC not to mention the exotic feel of listening with the fading and knowing you are doing it yourself without intervening wires...I am sorry but listening on the internet is just NOT the same!!!)<br />
OK, so back to Saturday morning. A quick check of twenty meters showed European signals coming in already at 1400 GMT. They were not strong but were readable. Many had a marked echo on the signals, indicating either multiple arrival paths or multiple backscatter effects. <br />
Sometimes when signals sound like that here in Texas it is when they are passing through the auroral zone and are generally from Northern Europe ( particularly Scandanavia) or parts of Russia. In this case, however, the echo was pronounced on many Southern European stations. Regardless of the mechanism, such makes copy of CW signals difficult because the delayed or echoed sounds tend to fill in the gaps or spaces between the " dits" and " dahs". <br />
On voice signals, it makes understanding the words very difficult. The effect can be quite interesting sometimes. I have heard instances where prop has brought signals from Asia to my radio by both long and short path at the same time. There have been times when the long path was actually stronger than the short path and the "echoed" syllables were actually stronger than the "original". I still remember the very first time I heard this effect and was amazed. It was in 1959 or 1960 while using my first, home built shortwave receiver and heard the Voice of America relay station from the Philippines early in the morning on 31 meters for the first time.<br />
In any event, there are a few things that might be tried to make either the phone or CW signals more readable. The first thing to remember is that the Automatic Volume Control ( AVC) or Automatic Gain Control (AGC) is doing its best to "level out" the signal. On CW particularly this means bringing up the gain when signals drop in level or are absent. This means the AVC ( or AGC) is actually aggravating the situation by making the echo and original signals the same strength.<br />
The first thing to try depends on whether you have a selectable AGC speed. If so, select the slowest speed. If not, it will be necessary to find some way to reduce the AGC effect. The only way to do this is to reduce the strength of the signal to the point that the AGC has no room to "recover gain". If you have an RF gain control, back it off. If you have switchable attenuators, switch them in. As long as the signal is audible, it matters not if the S-meter is swinging above S-9! If there is enough difference in strength between the original and echo signal you might find a point where it becomes more readable.<br />
The same can be said of phone or AM signals. The effect may not be as pronounced and in some cases will not help much, but it doesn't help to try. In some cases where the signal is " just ALMOST readable" every little bit can help! The technique works better on SSB phone signals than AM signals.<br />
One other thing you might try if you have more than one antenna is to select a different one. A different antenna might have enough of a different pattern that one or the other of multi-path signals might be reduced or enhanced.<br />
For hams working CW and trying to make a contact with a station marked by heavy echo, if its on a path going through the auroral zone, be aware that your signal is being affected in exactly the same way on the distant end. If signals are strong and the other station is not answering your calls even though you know he must be hearing you, its possible that the echo is making it impossible for you to copy you regardless of strength. The answer is to slow down. Not just with more space between letters with your keyer or bug sending letters at the same rate, but actually slowing down the letters to allow more space between "dits" and "dahs". <br />
I keep a straight key in the circuit wired in parallel with the output of my electronic keyer to allow quick and easy switching to a slower speed. Often this is the difference between being just heard and actually copied. This technique can also be used in other times than just multi-path or echo situations. Sometimes it can work in pileups and other heavy QRM or QRN situations. When its tough, whatever works !!<br />
During part of the weekend's listening, I switched away from the R-75 I had been using and fired up my old Hallicrafters SX-111. I still think this is one of the prettiest of the old boat anchors. When I was in junior high school, an older fellow who was in high school at the time and an active ham lived across the street from one of my aunts. I would visit him frequently and he was a great help with learning the code and generally learning radio in general. He had an SX-111 and I remember thinking it was really something. It was so much more stable and selective than the little National SW-54 I was using for SWL at the time. I guess when the opportunity to do some trading to get one years laer presented itself, it just would not do that I would pass it up. <br />
By the way, it is unfortunate but I have lost track of that ham over the years. His name was Lou and his call was K5HFR. That call is not active in any data base now and of course many people have changed callsigns or obtained vanity calls since then and I have not been able to trace him. Of course it could be he is no longer active.<br />
In any event, as I fired up the Hallicrafters it came to mind when I switched to forty meters and calibrated the dial that for some reason I was struck by the need to adjust the antenna trimmer. It occurred to me that many who use these radios today as collectors or who did not use them in " the day" may not know the purpose of this control.<br />
On these radios, tuning is accomplished by multi-gang variable capacitors. One section or "gang" tunes the mixer input, one tunes the local oscillator that generates the signal to convert the incoming signal to the Intermediate Frequency and if there are third and fourth gangs they tune the RF amplifier (s). They must all track together to maintain even gain across the band.<br />
The rub comes in when an external antenna is connected to the receiver Even if link turns on the coils are used to couple the input signal into the first tuned circuit, capacitance of the antenna system can "load " the circuit somewhat and cause some detuning, meaning the first tuned circuit will be pulled down in resonant frequency somewhat and might not track properly. The antenna trimmer control is used to counteract this effect.<br />
There are multiple ways it may be done. In some receivers, the antenna trimmer is simply in series with the incoming "hot" lead of the antenna, with the idea being series capacitance will minimize the capacitive loading effect ( see any electronics book on what happens when capacitors are connected in series).<br />
In some receivers the antenna trimmer is a small capacitor connected in parallel with the input tuning variable. In alignment, the first stage is tuned with the capacitor partially or nearly fully meshed. Then when the effect of additional capacitance from the antenna is added, by turning the antenna trimmer to a more un-meshed position, the effect of the added antenna capacitance is effectively nullified.<br />
It is not necessary for the receiver operator to know which method is used or in fact how it all works. All one must do is when one stops in any general part of the band is to rotate the antenna trimmer control for maximum signal. Any time you move an appreciable amount in frequency, just peak it up.<br />
This is not to be confused with the preselector tuning in some receivers. That is a whole 'nother deal!<br />
Hope all of this has been of some help and not just the rantings of an old guy! To many of you, this might be old hat, but to new guys or folks dealing with boat anchors for the first time, some of it might be useful. For those DX-ing the ham bands, it might be of some real use. As I have said before, none of these techniques should be taken as " the only way" but ways that I have found that work for me and hopefully will be of some assistance to others.<br />
Happy hunting and good DX!DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-35967468538273455982015-11-13T05:56:00.002-06:002015-11-13T05:56:31.357-06:00Was it Really a Poor DX Weekend? This past weekend ( November 7-8, 2015) was supposed to have been a poor DX weekend. And perhaps in some aspects, it was. There was some solar activity and there was to have been a solar mass ejection that was to reach Earth and cause radio blackouts and such.<br />
There were complaints on Facebook of dead bands and poor signals from stations that are normally heard well. There were also not the usual high strength DX signals obvious on the amateur bands. However, as is often the case in fishing, when the fish aren't biting in the usual holes, they might just be found somewhere else. It also might be that the openings were there, just shorter and during limited times of the day. And the third possibility, the DX signals were there, just from different places than usual and at lower signal strengths.<br />
In the case of this past weekend, it was a combination of all of the above. I am not certain what the mechanism of the appeared malaise might have been. It could have been a result of a hiccough on the sun, the CME or maybe just the overall low solar activity coupled with the change of seasons. In some cases it might have even been folks looking for broadcasters on frequencies they had abandoned with the seasonal frequency shifts and they were just in different holes.<br />
My own tuning actually started a little late in the weekend. It was Saturday morning a bit before 6 AM Texas time or about 1200 GMT that I woke without the usual alarm that during the week goes off about two hours earlier. <br />
After the morning ritual of feeding animals, walking dogs, making coffee, etc, I managed to get in front of the radios about 1220 GMT. The sun was already starting to lighten the sky. I used the R-75 and 80 meter quarter wave sloper ( which is actually a little long for the band, being about 80 feet long) top fed with the feedpoint up about 45 feet.<br />
I like to start with a sweep of the WWV and CHU frequencies first to get some idea of what the bands are doing. They are always there, with predictable schedules and signals and known antennas and give a good day to day picture of what generally is going on.<br />
It appeared things would be a little abnormal when there was no signal at all to be heard on 15 MHz. I didn't really expect to find anything but quickly checked the 20 and 25 MHz spots. Absolutely nothing.<br />
The 2.5 MHz signal for WWV was a blistering S-9 + 20 DB! WWVH was also audible very strong behind it. The surprise came with a check of the 3.33 MHz spot for CHU and it was already gone. The sun had come up at the transmit site and prop to the east was already gone. Well!<br />
Let's check 5 MHz. WWV was S-9+20 DB and WWVH from Hawaii was almost as strong! Then 10 MHz told the rest of the story. In the mild static crashes present locally that morning, I at first thought there was nothing there. But then came the top-of-the-minute beep and I knew something was there, but I had not heard the WWV voice. Waiting another minute for the time station cycle told the tale. WWVH was coming it about S-5, but WWV was not to be heard. Interesting!<br />
The 15, 20 and 25 MHz positions showed no sign of signals. A quick scan of the 10, 15 and 17 meter amateur bands showed nothing. Not too much of a surprise there. The only band that has been showing any signs of life even occasionally this time of the morning the past month or so has been 17 meters.<br />
So that's how we started Saturday morning. I knew it was probably too late, but I checked the 120 meter band, hoping perhaps to hear the Northern Australian stations, but they were gone. No signs of the Koreans or the Papua New Guinea stations on the 90 meter band. the closest thing to Asian DX I found was way up on 4940, one of the Chinese stations was coming in, actually rather well. Up the band a little bit radio Rebelde on 5025 was still S-9+20 DB but its band mate radio Havana on 5040 was missing.<br />
Up to 49 meters we go. On 5830, WTWW was blasting through, then 5875 BBC World Service from Thailand was about S-5, doing the usual Southeast Asia morning bounce on the S-meter. Another Chinese station on 5915 was not so strong, struggling to S-4 with the same bouncing level. <br />
I knew that stations up in the higher bands had probably changed their seasonal schedules and the usual spots I checked might not be updated yet on them, so I switched to the amateur bands. By now it was 1330 and I knew it was getting late for the Pacific on 40. Even at that, usually the Japanese stations roll in well past sunrise. However, it was not a major contest weekend that would draw large number of them out and even the small contest of the weekend, the Ukraine Contest, would not likely turn a lot of them out on 40 meters at this time. Forty would already be closed to DX for Ukraine with the sun well up there. And such was the case: only one lonely Japanese, JS1SUT was found on 7025. I should have gotten up earlier!<br />
The next fifteen minutes tuning around the band proved it all out. The short skip was in. Northeast US stations were already weak with their sunrise complete. The West Coast stations were ok and either in "local" QSO's or hopefully calling CQ DX. Only the Midwest stations were stoutly over S-9 and involved in local chats.<br />
Thirty meters showed the same thing. Mostly US stations either calling CQ DX without much luck or involved in US to US QSO's. What was the deal? The band was obviously open. Some of the stations calling CQ DX actually were showing signs of backscatter and echo from return skip from very distant locations. Had everyone just believed the dire predictions of bad prop because of solar activity and CME's? Were the Asian stations all on the higher bands working the Ukraine contest? Where was everybody? WWVH was if anything even stronger on 10 MHz now.<br />
A quick tune down just a bit from WWVH showed that there were broadcast stations coming through. At 9975 was KTWR from Guam at well over S-9 at 1358 GMT. The band was not dead, just open to a little different place than usual. Still not knowing for sure if the usual places where broadcast schedules were posted had been updated, I decided to default to the ham bands.<br />
A little aside here: It seems I have become a little spoiled by the readily available freshly updated station lists and schedules. I guess we all have gotten used to the almost " instant gratification" of easier station identifications. Its easy to forget how things were back when I started SWL-ing in the fifties and sixties where there were few updated lists. Even the WRTH was months behind some schedule changes the day it came out! And other lists such as White's Radio Log did not even have schedules, just long lists of frequencies used by the various stations. In those days it took long, sometimes tedious periods of listening to pull out an ID and then try to figure if what you heard in those fleeting seconds was accurate. Of course the stations in those days used Interval Signals or pieces of music around ID time that helped out. Those DX-ers who had the money and luck to have reel to reel audio tape recorders had at least a leg up in being able to record the ID breaks and play them back over and over in hopes of picking out the ID.<br />
So anyway, it was up to the 20 meter ham band I went without a lot of confidence, with all indications being that the Maximum Useable Frequency ( MUF ) was probably just over 10 MHz. Wrong!<br />
There were stations there! The Ukraine contest was underway and tuning up from the bottom of the band I immediately ran into K3WW at 1410 GMT on 14007 calling "CQ Test". He was fairly strong, RST 579, leading me to believe that this band, too, would be a fairly short skip affair.<br />
Wrong again! The next signal I ran into was at 14019.5 and was also calling " CQ Test" and working stations. He was not as strong, only about S-4, but readable. LZ5W from Bulgaria was having a fair time of it ( a signal heard often here during contests!) This was at 1413. <br />
The band at first glance did not appear to have a lot on it and for the uninitiated it may have appeared in poor shape. But after a few minutes of tuning around I discovered there WERE DX signals there, just not as strong as usual. <br />
There appeared not to be much coming through via high latitude paths. Even Canadian VE1DT at 1437 GMT spotted on 14012.6 was only S-5. I had run across him just dropping his call, apparently trying to attract a European that had been working other stations. Maybe the signal strength was just down because he had a yagi pointed away from me, because I eventually heard the station he was working. It was the first Ukraine station of the morning in the contest, UT0U, who as I listened came up from being almost in the noise to S-5.<br />
From there things proved to be a little easier. The DX WAS in fact there, just at a lower level. The band being open was confirmed when I heard N5WX on 14002.5 at 1442 on backscatter. The station he was working was another Bulgarian, LZ5R who was also about S-5.<br />
That proved to be the average signal strength of several Europeans heard over the next couple hours. I logged several Ukraine stations over that period and many Southern European stations. Some like HG7A from Hungary were marked by flutter. It would have been easy to give up on the band after a quick initial glance, but sticking with it proved that signals were, in fact, there.<br />
I would think that tuning SWBC bands would be similar. For those interested only in their regularly heard programs, there might be disappointment and a temptation to just turn the radio off. But for the DX-er wanting to put neat stuff in the log, it might prove to be more an opportunity. If the band is just open differently than usual, either longer or shorter or in a different direction for some reason, it would be an opportunity to log something else that might usually be buried under the "usual suspects" one would normally find there. Don't give up so easily!<br />
After our usual family brunch we enjoy on the weekends, it was back to the radio about 1700 GMT. The WWV sweep showed 2.5 inaudible, 5 with a barely detectable carrier ( not unexpected for nearly midday!) 10 MHz at S-9+ 20 DB but with some fading, 15 MHz at S-9+10 DB with slow fading and with WWVH audible behind it. Then came the big surprise. The 20 MHz WWV was booming in at S-9 + 30 DB!!!! Stronger than I had heard it in a long time. I posted such in one of my Facebook groups and right away a couple postings appeared of others in the Northeast US hearing it well, too! The 25 MHz WWV however, had a just audible carrier.<br />
The first thought was to check the 15 meter ham band. There were lots of signals there, but mostly single hop stuff. They were very, very strong, however. I am thinking the MUF must have been right around 21 MHz for those paths. Many like KD2RC and K6LL were S-9+20 DB. This was on the R-75 on the 80 meter sloper at 45 feet. <br />
One good catch during this time was a PJ6N on Saba Island. he was heard at 1820 GMT on 21005.2.<br />
Being curious, I took a look up on ten meters. I am not sure why, given the fact that the 25 MHz WWV signal was so weak. But it paid off. Perhaps the skip on 25 was just a little long for the path to Central Texas because ten was alive! Unfortunately, not with stations working stations, but the beacons were pouring in. For those who do not know, beacons are very low power stations put up by amateurs generally in the area between 28.2 and 28.3 MHz Most operate with between one and five watts with Omni-directional antennas designed to be indicators of whether the band is open. And it was. First heard at 1830 GMT was N7UTP on 28200.1.<br />
After that, over a dozen were logged in quick succession, including 4U1UN at the United Nations club station in New York heard with an S-9 signal on 28200.5 at 1832.<br />
Interestingly, even though the band appeared open, there was little activity. Once again, it appeared the "news" about poor prop or predictions of same might have deterred folks from even looking or making more than a cursory tune across the band. There was one island of high activity, however, around 28017.2 where TG9ADM in Guatemala had set up shop. He soon was working a very busy pileup.<br />
A quick drop back to fifteen meters around 1900 showed some activity prior to the beginning of the ARRL Sweepstakes contest. One really good one was found when a good sized pileup of rather weak stations was found around 21009. After considerable listening and pulling out one letter at a time, it was determined that at the bottom of the pile was 9Q6AL from the Democratic Republic of the Congo! Careful listening and diligence pays off!!<br />
From then on through the afternoon it was hopscotching between bands and the TV for college football. At 1933, a new one for me on 17 meters was VP2MVI from Montserrat on 18072. Don't know how I had missed that one in the past, but sometimes that's the way it works. One that would seem to be a "given" somehow either gets missed or just isn't heard. That filled the line across the tally sheet for Montserrat for all bands 160-10.<br />
The afternoon on ten meters turned up many South American and Caribbean stations. The catch of the afternoon for fifteen meters was V51YJ in Namibia at 2010 on 21012 working a spirited pileup. Just in time, too because as the Sweepstakes Contest began a little later, the US stations would have pretty well covered any possibility of deep DX, at least on CW. The rest of the weekend would have to be either on phone or tuning the WARC bands ( 30,17 and 12 meters) which are contest free by convention. <br />
Even though the ten meter beacons were still coming in and a beehive of Sweepstakes Contest stations were audible on ten meters, twelve did not yield much. Obviously the band was open, because PY3NA was coming through calling CQ on USB at 2314 GMT on 24945 with a pretty good signal. The background noise indicated the band was open. <br />
I don't know how many of you have noticed the actual " sound" of an open band. There is a sound other than that which is locally generated noise that is often heard that can give you the feeling that the lights are on but nobody is home. I do not know if it is the aggregate noise from other places that props in like other skywave signals or just what it is, but sometimes you can actually hear it, sometimes even with a little selective fading in it. In the old days when cars generated spark plug noise you could sometimes hear the total sum of that adding up to provide a background floor in an open band.<br />
I had a friend who is now a silent key who spent time in Panama and on Swan Island on work assignments who told of many times hearing Stateside or other ignition noise propping into Swan Island when there were no engines running on the island at all.( Swan Island is very small and off the coast of Honduras. In the 1960's it was the center of some controversy as a supposed location of a station known as Radio Americas that broadcast on 1160 and 6000 KHz carrying anti communist programming aimed at Cuba. That story could almost make a novel by itself!!!!) But I wander afield again...<br />
While there were few signals present, it was a matter of just finding where the band is open and drop the hook there. In this case, it was back to 17 meters. As it was getting close to sunset local Central Texas time, the hope was to find some Asian or Pacific stations. They were indeed there.<br />
It was a classic late-in-the-day, upper-band condition. South American and Japanese stations were showing up in large numbers. At 2318, I first found PX5Z in Brazil and JO1WXO from Japan just a kHz apart on 18076 and 18077 respectively. The dual 250 Hz filters in the R-75 easily separated the two The pattern remained the same as the band was scanned.. South American stations were running about S-7, the Japanese stations were running S-5 or lower. They were not jumping out of the radio by any means, and if you spun the dial quickly just doing a "quick cruise" you might miss them. But slow and careful tuning would turn them up. In conditions like this, I often open the selectivity up to " CW wide" or even a narrow SSB position while looking for stations in the grass, then if I find a group of stations, THEN tighten things up and gingerly turn the dial to pick out the goodies. Over the next half hour I filled almost a complete page with callsigns on an afternoon when " the bands are crummy"! <br />
The one that would have been missed if I had just given up and said " oh there's nothing here" was found at 2334 on 17 meter sideband, one that would be good in anyone's logbook: VP8LP in the Falkland Islands on 18155 working a fair sized pile. Interestingly many of the stations he was hearing and working were inaudible here..<br />
After dinner, one more check of the bands were made before a little family time. As is often the case, the upper bands sounding bad were an indication that the lower bands would be fine. Eighty meters handed up EA8ZS with a fair signal even through the evening static crashes and Sweepstakes Contesers on 3515 at 0203 GMT on the " next day" GMT though it was of course, evening in Texas.<br />
Sunday was going to have short time for listening because of an impending visit by grandbabies<br />
and playing of a different sort!. I got on for a few minutes at 1200 GMT or 6 AM local time and fired up the R-75. The WWV sweep showed 2.5 MHz WWV at S-9+30 DB, CHU on 3330 at S-7, WWV on 5.0 at S-9+40 DB(!!) with WWVH well audible behind it. On 10 MHz, WWVH was again on top about S-5 with lots of QSB and WWV inaudible. There was nothing audible, not even detectable carriers on 15, 20, or 25 MHz. <br />
Someone had mentioned on Facebook FEBA from their Philippines Manila site coming in to England, so I made a quick check there. They were S-7 on 9400 and S-5 on 9430, the opposite being stronger I Texas than in England where the poster had shown 9430 to be the stronger of the two. Thirty-one meters is always interesting and surprising around sunrise and sunset. This was an interesting logging in particular because he was most probably hearing the signals coming to his location from the East while I was most probably hearing them coming from my West! This is one of the little observations that makes this hobby fun. <br />
With the little time I had left, I dropped to the "basement " of the HF range and checked for the Northern Australian signals. VL8T on 2325 from Tennant Creek was S-4 but actually readable on a morning where the noise was very low here. Its band mate VL8K on 2485 was stronger at S-7. I remember wondering if there was that much difference in prop over 160 kHz or if there was some difference in the characteristics of their transmitting antennas.<br />
Up the band a bit at 2850 Pyongyang, North Korea was rolling in at S-9, better than its transmitters on 3220 and 3320 which were about S-5. <br />
One thing I miss from these morning sweeps is the old HCJB signal that held down 3220 for so many years with its local language programs. I guess times change, but the loss of their facilities in Ecuador marks a change I could have done without!<br />
The Voice of the People from the other side of the Korean DMZ was coming in well on 3480 and 3912, along with its jamming counterparts.<br />
The last loggings of the morning and of the weekend was Radio Nikkei on 3925 which was an amazing S-9+10db and sounding good. The last logging was actually a " no log" as it appeared, and was noted in the log, that Radio Nikkei on 3945 appeared to be missing!<br />
It was not too bad for a weekend that so many folks had moaned about as being poor! I had chosen to spend most of the time in the ham bands because of uncertainty about schedule info being updated for the broadcast stations, but it might have been a good time to confirm what I believe about band conditions. Often when the "regulars" are not heard, it is not because the band is dead, but because it is open to somewhere else. The band may be longer or shorter than usual. There may be other things to hear in the absence of the regulars. Or there might be other targets to be sought out on other bands. Often the WWV sweeps can tell you things about that. For those on other continents where WWV and WWVH might not be useful as "prop" beacons, there might be other stations you can use as barometers...maybe even other time and frequency standards or stations that you regularly hear at certain times. Checking the barometers can often save you time and tell you where to drop the hook to find the fish!<br />
For those listening mostly for programming, it might be a time to find other programs that you do not usually hear. For the DX-er, its often a golden opportunity to hunt for new things on new bands. It is not a time to give up and default to the TV. There are enough differences in conditions on the different bands stretching from LF to 30 MHz that there is always something to be found to put into a log!<br />
Good hunting!<br />
<br />
DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-27061602052326158312015-11-06T05:38:00.001-06:002015-11-06T05:38:57.345-06:00Crystal Filters and Phasing While looking at older receivers for SWL DX purposes, there are a few features that are particularly helpful. After the usual " default " requirements of at least one tuned RF amplifier stage and at least two IF amplifier stages comes some means of tightening selectivity.<br />
When it gets down to it, almost all boat anchor receivers that have two IF stages with a 455 kHz Intermediate Frequency ( which covers about 95% of those built in the 50's, 60's and 70's) the selectivity of all of them are pretty much equal. About all you can count on is about 10 kHz selectivity without some kind of additional selectivity enhancement. This is not to say that two broadcast stations 5 kHz apart could not be identified, but that if one was particularly stronger than the other, there would be considerable "slop" between the two of them and listening would not be comfortable. CW reception on the amateur bands would be possible but digging out the real DX would be difficult because of interference from neighboring stronger signals.<br />
We have covered the Q multiplier in a previous post. The next selectivity enhancing feature is the crystal filter. This was considered a significant expense to add to receivers in that time period and would boost the price considerably. Now because of collectors looking for even the lower level, or entry level receivers, things have kind of evened out.<br />
The simplest form of crystal filter consists of one crystal cut for the Intermediate Frequency and at some point in the IF chain in series with the signal path. The crystal will pass frequencies on its frequency fairly well, with response falling off rapidly on either side of its resonant frequency.<br />
The peak on a single, simple crystal filter is fairly sharp. The center frequency is the resonant frequency with response falling off in a curve. The selectivity figures for receivers are usually referred to in how many DB down the signal is from the resonant frequency. The points usually used are 6 DB down and 60 DB down. The difference between the two gives some idea of the sharpness of the filter or tuned circuits in the radio. The 6 DB down figure indicates the frequency separation at which the signal strength is half what it is on the peak. The 60 DB down figure indicates the frequency separation at which all but the strongest signal would be practically gone.<br />
A graph of the response can be either very "pointed' or sharp, or slope down gently. The lower parts of the curve are referred to as the "skirts". The closer in the skirts as the response goes down, the sharper the selectivity. <br />
More complex filters can be built to shape that response. These filters make use of more than one crystal and are sometimes referred to as " crystal lattice" filters or " multi pole" filters. The purpose of the filter determines how the lattice is set up. A filter designed predominantly for cw operation might be made up of crystals very close in frequency to give a very sharp, narrow filter with steep skirts. There might be a design that leaves the top a little flat to avoid ringing in the filter.<br />
A multi pole filter designed for Single Side Band or AM might be made quite differently. It would be made of several crystals spaced in frequency to give a fairly flat topped response over a 2.5 to perhaps 6 or 8 kHz bandwidth to allow the sidebands of the SSB signal or AM signal to be passed without muffling the sound. At the same time, the multiplicity of crystals will also insure very steep skirts outside the desired passband. These kinds of filters are often optional filters and are usually found in more complex, communications grade receivers. They are also very expensive!!<br />
If you are lucky enough to have a receiver with positions or sockets for optional filters, such as the Icom R-75 or others, you may have a choice of purchasing filters made by the receiver manufacturer or other after market filters made by other companies. When looking at the information for these filters, you will often find charts and graphs that illustrate the responses of the various models of filter. Careful study should be given to these graphs with thought toward what kind of listening you plan to do. Casual listening to AM signals on shortwave broadcast bands or Medium Wave might call for a slightly wider bandwidth while serious DX-in and digging for weaker signals might call for something sharper. But once again, I am wandering a bit from the central subject!<br />
Most common boat anchor receivers have the more simple, single crystal filters. The question sometimes is, which ones have them and which ones don't. With Hallicrafters, this is easy. The receivers without filters have a model number with just the "S" and a number, such as S-118, S-120, S-85, S-38, S-40B etc. The receivers with the filters have an "X" in the model number, such as <br />
SX-62, SX-71, SX-96, SX-99, SX-100, etc. With the others, its a matter of looking them up.<br />
When looking at a receiver, it is often easy to tell by reading labels on controls. If there is a selectivity switch with multiple positions, its a pretty good clue. If there is a control labeled crystal phasing" or just " phasing" it is a certainty! <br />
Using a crystal filter is a little easier than using a Q multiplier, but there are some things to know beyond just turning it on or setting to a tighter selectivity position. The phasing control affects its operation by in some ways bypassing it partially and in some ways shifting its peak and null frequency a little. Some folks get the idea its like a passband tuning control, and while it may act a little like that, it is not exactly what is going on.\<br />
While the crystal filter has a passband narrower than the bare IF amplifier, it also has some nulls and secondary peaks off the main frequency. The phasing control affects them somewhat. If you are tuning casually on AM, I find it useful to have it set off to one side a bit. Then when a station is encountered that you are interested in, rotate the phasing control back and forth to get the best response. You might find that one of the off peak nulls might just take out a pesky heterodyne, though it may affect the desired signal a bit.<br />
A good thing to do when first obtaining a receiver with a crystal filter is to conduct a little "experiment and training" session. If you get a manual with the receiver, there will probably be a general discussion of the operation of the various controls including the crystal filter. There may even be a graphic representation of the crystal's response. This can be helpful if you can picture what is happening as you are tuning and trying to get the filter to help you.<br />
As part of the "experiment and training" session, the best thing to do is find a good, steady signal, preferably a not-too-local broadcast band station. If the receiver has an S-meter, you can get a really good picture of what is going on. <br />
First tune the station in with the crystal filter "out" or selectivity control in the broadest position. Peak the signal carefully with the receiver tuning control. Then switch the filter in or go to the next tighter position. You might actually see the signal strength drop a bit. Depending on the alignment condition of the receiver and the insertion loss of the filter, it might drop a little or it could drop a lot. All crystal filters have some insertion loss and its not unusual to see a drop of an S-unit or two even on those in the best condition.<br />
Turn the phasing control back and forth and see if the signal peaks up or drops down. If it peaks, set the phasing control for maximum signal. Then carefully rock the tuning dial back and forth and see if you can get any more out of it. Go back and forth a few times to make sure you have it at its highest. Note the position of the phasing control for future reference. This will be the position you will want it in while you are in the general "hunt" mode for AM or broadcast stations.<br />
Next watch the S-meter and tune the dial off the station, then slowly go across it to center and beyond. Note the actions of the S-meter. There should be the one main peak, some dips and maybe a minor peak again, probably just on one side. These filters are not usually perfectly symmetrical, with the symmetry somewhat affected by the position of the phasing control.<br />
This exercise will give you some idea of the basic shape of the passband of the filter.it will also give you the best starting point while tuning.<br />
After noting the best " center" position for the phasing control, center the station up well and move the phasing control back and forth, noting the actions of the s-meter. This will give you some feel for the shape or impact the control can have when you may need it.<br />
Some users of these radios will come away with the idea that the crystal filter is of no use or help or has no effect. Going through this little exercise should cure that notion. Often those who get that impression are just turning knobs aimlessly and don't get much of an effect simply because the randomness does not take them into an area where the effect can be seen! <br />
The crystal filter can really help out on CW and SSB. To set up for CW tune to a quiet place or disconnect the antenna. Put the selective switch in the narrowest position. Turn the phasing control off to one side or extreme range of its setting.Turn on the Beat Frequency Oscillator or set the radio in the "CW" mode. Rotate the BFO pitch control back and forth, listening for a light "swishing" sound as it moves through the receiver passband. Find the lowest pitch spot which should indicate the center of the passband. Note this position. Hopefully, if the receiver does not need a serious realignment, it will be near the center of the travel of the control. Remember this position for future use. Now offset the pitch control one way or the other just slightly from that center position so that it is toward one side of the center of the passband. Turn off the BFO.<br />
Now with the antenna reconnected, tune in a steady AM carrier, preferably a medium wave station within groundwave range but one not too strong. Center it up in the passband by either watching the S-meter or listening for the slight swishing sound that sort of "bottoms out" as you get it centered. The selectivity switch if there is one should be in the narrow, or if there are multiple settings, in the narrowest position.<br />
Turn on the BFO. Rotate the pitch control back and forth, finding the zero-beat position over the carrier you have tuned in. It should be near or at the spot where you had centered it earlier if your tuning has been careful. Now offset the pitch control slightly giving a heterodyne of a pitch that would be comfortable copying CW for you.<br />
A short aside here: Normally I would say to set up for copying with a low pitch. However, with simple crystal filters anything much lower than 800-1000 Hz might put the signal on the " other side of zero beat" too close to allow what is known as single signal reception. After you finish this set up you can experiment with what pitches give the best compromise between copying at a low pitch and selectivity.<br />
Now leaving the pitch control in the same spot, using the receiver tuning, tune back to zero beat and on to the other side where the pitch comes back up to about the same pitch as you had when you set the BFO. Now adjust the crystal phasing control for minimum signal or lowest indication on the S-meter.<br />
Once this is done, with the receiver tuning, go back through zero beat and take a look at the signal strength of the desired signal. It should be significantly higher than the nulled side. With some receivers, this may take a little juggling of the pitch control, offset and phasing adjustment to get the effect you want...as close to single signal reception of CW as you can get. Finding the " sweet spots" sometimes takes a bit of experimentation, but once you have found them, you will find that you are getting the maximum effect out of your crystal filter and can most easily separate CW stations on a crowded band! Once again, the "art" of tuning comes into play and this is another example of operator skills that can be developed to get the most out of any receiver.<br />
For SSB, once again turn the BFO pitch "off". You will find that there will need to be different settings for BFO pitch and crystal phasing for Upper Sideband ( USB) and Lower Sideband ( LSB).<br />
In each case you will want to have the desired signal centered in the receiver passband but because of the nature of needing to have the missing carrier re-injected in different places to make the SSB signals audible you will need to have the BFO pitch control set differently for the two modes. And to have the crystals peak and null features in the right spot, there will need to be different settings of the phasing control for the two modes as well.<br />
Fortunately, finding signals that are definitely known to be USB and LSB is easy. By convention in the amateur bands, operation on 160, 80, and 40 meters is on LSB while operation on 20,17,15,12,10 and 6 meters is on USB ( there is no phone operation on 30 meters).<br />
Once again turn the BFO " off " or set the receiver into the AM mode. Tune in a signal on one of the bands where LSB is used and pick out a signal that is kind of by itself to make set up easier. You will not be able to understand the talk at this point, but as best you can, center the signal up in the passband. Selectivity should be in the "narrow" position if there are just " wide" and "narrow" positions or in one of the mid selectivity positions if there are multiple selections. Set the crystal phasing control off to one side or extreme.<br />
Turn on the BFO and rotate the pitch control until the signal becomes intelligible or sounds most natural. If the signal is really strong, you might have to back off on the RF gain or sensitivity control on some receivers.<br />
A this point there needs to be another aside. If during your initial CW set up you found that the BFO hit the center of the passband well off center of its range, the receiver may be slightly out of alignment and you might not be able to get the control " far enough over " to reach the intelligibility spot. If such is the case, its ok to "cheat" a little and move the receiver tuning slightly to hit the spot. At some point a receiver alignment would help this situation out, but most basic crystal filters are not so super selective as to make tuning in the signals with a little "cheating" impossible.<br />
Once the signal is intelligible and the sound is comfortable to hear, use the receiver tuning to move the signal through the passband, going toward the zero beat or in the direction that makes the voice lower pitched until you are on the " other side " of it and it is unintelligible. Make sure you are completely on the " other side" and are hearing the signal effectively " upside down". At this point, adjust the phasing control for minimum signal. Then take the receiver tuning control back through zero beat and to the position where your signal is intelligible. It should still be readable and not too reduced in signal strength. As with the adjustment for CW, there might need to be a little jockeying of the positions of tuning, BFO pitch and crystal phasing, but with a little experimentation you can find the settings that will give maximum intelligibility and selectivity. Note the positions of the BFO pitch and phasing controls and when you start looking for LSB signals, preset them to those positions and you will find your initial search for signals much easier.<br />
Now go to a band where you know USB signals are located and repeat the process. Again, note the positions of the controls for future reference. You will find that the BFO pitch control is at the opposite end of its range from where it ended up for LSB signals. <br />
Again, every receiver is a little different, every crystal is a little different and every receiver alignment condition is a little different. It take patience and practice, practice, practice to get to the optimum settings. These initial settings will get you " into the ballpark" and you may find slightly different settings as you further learn your radio. Under certain QRM conditions you might find yourself playing with the controls a bit to hear the station you want. But always going to these initial settings will save you a lot of time and prevent simple "flailing in the dark" trying to tune a signal in and generating a lot of frustration. I cannot over-emphasize the existence of a real art to tuning in DX!!<br />
One other note about tuning SSB signals on older boat anchor receivers. Many were built before what are know as "product detectors" were routinely put in radios. In fact, many were built before SSB was routinely used in amateur bands and was predominately found in commercial point-to-point operations. They were not designed for optimum SSB operation. That does not mean they cannot do an admirable job in copying SSB signals. It DOES mean that some additional care will be needed to make it possible. <br />
If there is difficulty in getting the SSB signal fully intelligible even when you hit the position where the pitches appear right, back off on the RF gain or sensitivity control. It may be that the signal is too strong for the BFO injection level of your receiver. Tuning SSB signals with these receivers sometimes requires more frequent adjustment of RF gain to make it work out.<br />
By the way, the description of tuning in SSB signals with a BFO pitch control outline above also applies to the newer portables that can copy SSB. The method up to the point of adjusting the crystal phasing should be the same to avoid some wild-eyed frustration in getting the signals audible. For those portables with pitch controls or an equivalent there-of the method outlined will help considerably.<br />
One other note about crystal filters and receiver alignment. Because crystals can "wander" somewhat with age and because quality control may not have been the best with some manufacturers, the crystal may not be centered exactly on 455 kHz ( or what ever the design Intermediate Frequency of the receiver might be). For this reason, when doing an alignment of these receivers it is highly important that a signal generator be fed into the IF's before the filter, meaning in some cases may need to be fed into one of the grids of the mixer tube. It also means that instead of arbitrarily setting the signal generator at 455 that it be swept slightly back and forth two or three kHz to find the peak of the crystal ( with the phasing control off to one side or extreme) and aligning the IF to the crystal. The difference of one or two kHz will not be enough to affect the tracking and calibration of the main tuning. The important thing is that the Intermediate Frequency amplifiers be peaked to the frequency of the crystal because that will keep the narrowest response possible. The frequency of the IF peak can be shifted a little, but the response peak of the crystal cannot!<br />
One other note about alignment at this point that applies to any boat anchor regardless of whether it has a crystal filter: Once alignment has been complete, turn on the BFO and swing it through its range with the signal generator still feeding at IF signal in. You should always have the signal generator output level set at the lowest setting possible to allow alignment. Rotate the BFO pitch control for zero beat against the signal generator carrier. Note if the BFO pitch control is at the center of its range. If it is not, look in the service materials for the receiver and find a below chassis adjustment for the BFO frequency. It will probably be a slug tuned coil. Once you find it, set the BFO pitch control on the front panel to the center of its range, then bring the BFO frequency to zero beat with the other adjustment.<br /> Older receivers with crystal filters are not all exactly the same, but the principal of the operation is. There are still differences in quality of components and even of the crystals themselves. The single crystal filter may not be as tight as some of the multi pole filters that appear in the more expensive radios, but they do tend to be more effective than some of the ceramic filters that appear in some of today's budget portables.<br />
Once again, I will note that the methods described here are not to be taken as " the only way" to do things, but are the methods I personally have found useful in fifty plus years of spinning the dials. They work well for me and have put 326 countries in the log.<br />
For those who enjoy tuning with the vintage receivers and capturing some of the adventure of the golden age of SWL, a crystal filter equipped radio will provide the additional satisfaction of greatly improved selectivity. There is something special about tuning one of these "beasts" though for a beginner, there are many things to learn and some frustrations to avoid. They are not necessarily for the " dial in the frequency and forget it and listen " crowd. For that group, even the most expensive, digital dial and DSP equipped radio might be found to be frustrating for them. But for others seeking a bit of adventure from the hobby the boat anchors do offer a level of performance and sound quality that is difficult for many of the inexpensive portables to match. DX-ing, like life in general, offers a bit more to those willing to put a bit more into it ( a little personal philosophy there, too!!)<br />
Whatever type receiver you chose to use, the important thing is to learn how to use it to the fullest of its capabilities. Tuning shortwave is not like turning on your cable-fed television and dialing to a channel number and having a station pop up! <br />
Good DX. Good Hunting!DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com2tag:blogger.com,1999:blog-1544382238317398005.post-83748195214728707242015-11-01T09:21:00.001-06:002015-11-01T09:21:54.096-06:00Boat Anchors and Q- Multipliers There can be lots of arguments about whether its better to use one of the new high tech radios for SWL or BCB DX-ing or whether to go with a more complex table top model. My own experience has been that the table top unit gives better performance for digging out deep-buried DX but that a high tech portable in the hands of a skillful user can do very well. On the other hand, to get the most out of the table top radio also requires a certain amount of skill and getting to know the radio.<br />
The new portables particularly have the advantage of providing much better frequency readout than many of the old desk top "boat anchors" could provide, while the older receivers can often provide more robust handling of very strong signals and deal better with connection with outdoor antennas.<br />
The older rigs can also provide better selectivity than the new portables. They do this through the use of crystal filters and in some cases Q-Multipliers.<br />
The issue of Q-multipliers came up on a Facebook Group of which I am a member this week and questions about its use and "whether it was working or doing anything" resulted in a short note to the poster describing the use of the device in a rather abbreviated way. I thought perhaps sharing a more detailed information about their operation and use might be in order here.<br />
Just what is a Q-Multiplier? Well the abbreviation "Q" in the electronic sense refers to the "Quality Factor" of an inductor or tuned circuit. Without getting into the esoteric details, what it boils down to is it generally can refer to selectivity or how broadband a device might be. A tuned circuit or antenna with a High Q would have a narrower bandwidth whereas a tuned circuit or antenna with a Low Q would tend to be rather more broadband. There are many factors that go into determining the Q of a coil or antenna. In the case of coils, wire diameter, turn spacing, diameter of the coil winding and resistance of the wire or surrounding circuit are the major factors, along with any loading on the circuit. The bandwidth of antennas is a whole other issue that could take up its own entire article!<br />
The name " Q-multiplier" then can almost be surmised as being a device that somehow "multiplies the Q" of a circuit or in this case, does something that increases its selectivity. In superheterodyne receivers, the real selectivity takes place in the Intermediate Frequency amplifiers. The superhet design basically converts all incoming signals down to one frequency where high gain, stable amplifiers are easier to design to operate in a fixed-tune mode. The concept as created in the 1920's and 30's has remained with us ever since.<br />
Different boat anchor designs, just like different new portable designs, came with different price tags depending on the complexity of the circuits and the cost of the components placed in them. The basic design that is of most use to DX-ers is one that has at least one stage of tuned radio frequency amplification ( one R.F. Stage) and two stages of Intermediate Frequency amplification ( two I.F. stages) Most single conversion radios had a 455 kHz IF. Some dual conversion radios had a 1650 kHz First IF and 455 kHz Second IF. The triple conversion receivers often made a further conversion to 50 kHz.<br />
Q multipliers have been around since the very creation of the superhet design as a means of improving selectivity in the Intermediate Frequency stages. It basically brings the advantage of a regenerative receiver to add to the greater advantages of the superhet design it had been determined earlier that the use of feedback or regeneration in an amplifier stage would artificially increase its Q by overcoming losses in the circuit. A small portion of the output would be coupled back to the input at a level just below that which would cause oscillation. <br />
This can actually be done in the IF stage itself to a degree but is difficult to control because of the action of the Automatic Gain Control circuits. When the gain goes up in the absence of a signal,the stage is pushed more toward oscillation. If the internal feedback is set at this level, it does not do much good when the gain of the stage is then pushed down by the presence of one or more stronger signals, which is the exact time more regeneration is needed.<br />
The device covered by the term Q multiplier generally refers to what amounts to a separate IF amplifier operating in parallel with those existing in the receiver. It is often connected to either the plate of the last converter tube if there is but a single IF stage or the plate of the first IF amplifier stage if there is more than one. It must be tuned to the same IF frequency as that of the receiver to which it is attached. For the " add-on" devices this was most frequently 455 kHz.<br />
I am not sure if anyone knows who first published designs for outboard Q multipliers or extra circuits of one built into a receiver but they have been around for a long time. They were also around in abundance as add-ons in the form of kits in the 50's and 60's, most notably the Heathkit QF-1 and its descendants. Some receivers, including many of the general coverage Heathkits had jacks on the back to allow easy connection of the Q-multiplier.<br />
There are also many construction articles on how to build one and connect it to a receiver in the archives of many magazines such as QST, CQ, Popular Electronics and Electronics Illustrated. Older editions of the Radio Amateur's Handbook published by the American Radio Relay League also have information on the theory, design and actual construction and connection of them. I am sure the same goes for Radio Society of Great Britain and organizations in other countries. Most of these articles and designs tell of how power to operate Q-multipliers may be taken from the receivers to which they are to be connected and how to set them up. Others may be built with their own internal power supplies.<br />
Using the devices is a bit of a learned art, much as the actual tuning of a receiver is such. While instruction may be given, there is nothing like the "hands on" practice of making them work to get the most out of them.<br />
Most Q multipliers have the same minimum controls: Tuning and some form of gain control. It might be labeled " selectivity" or in the case of the Drake Q multiplier meant to be used with the famous 2B receiver it is called " Q balance". Some many have additional controls to chose between peaking and notching signals. The Heath also had a "Broad" and " Narrow" switch. Some radios with built in Q multipliers may not have the tuning control. <br />
I will leave the adding and/or building of a Q multiplier to other articles. Here I will cover the operation and use of one. <br />
The first thing to do is turn the device on and set the "gain","selectivity" or whatever form the operating level control might be to about mid scale. Start with the radio in the AM mode and tuned to a quiet spot or with the antenna disconnected. Then rock the Q multiplier tuning control back and forth and listen for a "swishing" sound. If you don't hear one, run the "selectivity" control up a bit more ( clockwise) until you do. Note where on the tuning control the "swish" seems to have the lowest pitch or sounds like it is " bottoming out". This will be the spot that corresponds to the center of the receiver's passband. Note that spot for future reference. Depending on the alignment of the receiver and the Q multiplier, this might not necessarily be at the center of the control's travel. This can be corrected but should not be attempted without proper understanding of the receiver and Q multiplier circuit operation. In no instance should an attempt be made to realign the IF stages without a signal generator of known frequency calibration or proper calibration and tracking of tuning on the main tuning dial can be negatively affected!!<br />
For tuning AM signals, it is best to start with the Q multiplier tuning set in the center of the passband. Once the signal is tuned in and centered, you can try swinging the tuning back and forth to get the best readability without slicing too much off the sidebands. If the selectivity is too tight, all the highs will be sliced off and the station will sound muffled. You can try tuning off to one side or the other with the Q multiplier tuning which can act much like passband tuning. <br />
If there is a strong heterodyne or splatter interference on one side you can try tuning the station in with the main tuning placing its carrier on the edge of the passband placing the splatter farthest from the center, with the desired side centered in the passband. Then crank up the Q multiplier and make adjustments with its tuning.<br />
This is where the art of using the device comes in. It is only with practice and patience that the full effects and possibilities of this device can be learned and attained.<br />
It is on cw and single sideband that the Q multiplier can really show its maximum potential. There are probably a number of " set up " methods for cw reception with one, but here I will describe the one I have used and found to be one that at least works for me!<br />
The first method involves a receiver with a variable pitch BFO. The first step is very similar to that with which the Q multiplier tuning is determined. Tune the receiver to a quiet spot or disconnect the antenna. Turn on the receiver's BFO ( Beat Frequency Oscillator) and rock the pitch control back and forth. you will hear the "swish" similar to what was heard with the Q multiplier tune set up. Once again the "swish" will " bottom out" or have a noticeable lower pitch when it is moved through the center of the passband. This is, of course, not where you really want it...it is where you want the desired signal to be, so at this point move the pitch control a slight amount to the right or left ( as you turn the knob) from center.<br />
For practice, connect the antenna and tune in an AM signal that is not too strong, but which is of a fairly steady strength. Probably the best place and time to do this is in the daytime with an AM broadcast station other than a powerhouse local station. If your receiver has an S-meter. carefully center it up for the maximum meter indication. If you have no S-meter, by ear rock the tuning back and forth and with practice on a weaker signal you can hear when the signal is centered. If the receiver has fairly good selectivity to begin with you can hear the little " swish" as the carrier moves through the passband or you can hear the lessening of the high frequency sounds on the sidebands as its is centered.<br />
Again, this ability to notice things comes with practice. The accurate and careful tuning of a receiver is much more than just dialing the tuning to a spot and finding something. There are a number of subtleties that can be recognized only with practice and that are often hard to describe in words. The receiver cannot do the work for you, no matter how complex or expensive it may be. I think I have noted before that a skillful operator can pull out DX with a simple receiver that a casual tuner cannot find with a much more expensive one. Practice, practice, practice and learn to take advantages of the capabilities and avoid the weaknesses or your receiver!<br />
But I digress. Once you have your " test signal" tuned in, turn on the BFO and rock the pitch control back and forth. Listen for where the " Zero Beat" occurs,. The zero beat definition will be obvious as you do this. It is the point at which the pitch of the heterodyne of the beat frequency oscillator goes lower and lower in pitch and at one point becomes "zero".<br />
Note again where the zero beat occurs on the pitch control. If your tuning has been careful, you should notice that it is at or very near the same spot as you noticed the lowest pitch " swish" when rocking it when listening to no signal.<br />
At this point, leave the receiver tuning alone and move the pitch control to one side of zero beat or the other to obtain a pitch comfortable for you to listen to cw. Then turn the Q multiplier on and set the selectivity control fairly high. If there is a "peak-notch" or " peak-null" switch, set it to peak. Now move the Q multiplier tuning control to peak the level of the resulting beat note. Or watch the S meter for a peak. Run the selectivity control as high as you can without the device going into oscillation itself. If you keep it right on the ragged edge of oscillation you will be at the tightest selectivity point. <br />
Now to test if your adjustment has been good, move the receiver tuning control back through zero beat and back up the other side. If the Q multiplier is doing its job and your adjustments have been proper you should notice that as you tune to the other side of zero beat, the signal should be much weaker. In other words, on one side of zero beat you will have a strong signal and on the other side of zero beat it should be much lower. The idea is to have the BFO injection offset in the receiver passband to make any signal that would have the same pitch as your desired signal to be out of the passband on the other side of zero beat.<br />
This results in what is called " single signal" cw reception. Otherwise, as you tune through a crowded band, each signal will actually show up twice, resulting in effectively an undesired signal giving QRM to a signal that you might otherwise hear from the other side of zero beat. Effective set up of BFO pitch and Q multiplier tuning can thus for all practical purposes doubled the tightness of selectivity of the receiver! The ability to bring this about effectively comes only with practice. It is best done listening to a good steady carrier and doing the set up over and over and finding the best settings for your particular receiver.<br />
Tuning in single sideband signals is a bit more complex. Without the Q multiplier on, tune in a good fairly steady SSB signal and practice making it intelligible. Once again, start with the BFO offset to one side or the other of the center of passband. This is why you want to remember or note the position of the control at dead center zero beat. You want to have the desired SSB signal centered in the passband and the BFO injected on a frequency offset and near the edge of the passband. Just as with single signal cw reception, you will eliminate QRM coming from " the other side" of the BFO.<br />
The trick is the required position of the BFO pitch control is different for upper sideband ( USB) signals and lower sideband ( LSB) signals. This, again, will take practice to determine. One thing that makes it a little easier is the fact that by convention, on the amateur bands, everyone operates lower sideband ( LSB) on 160, 80, and 40 meters and upper sideband ( USB) on 20, 15,17,15,12 and 10 meters.( there is no phone operation on 30 meters).<br />
Once you have a known LSB signal tuned in, juggle your dial tuning and BFO pitch to obtained the best overall intelligibility and note the position of the BFO pitch control. Then turn on the Q multiplier and starting with the selectivity control somewhat lower than for CW, adjust the Q multiplier tuning for most intelligible or strongest signal and run the selectivity control up until it starts to "bite" into the high frequencies of the voices and begins to make them sound muffled. Note the positions of the controls so you can always come back to them.<br />
Then do the same with an upper sideband signal. Note those control positions. As you listen more and more, you may refine them somewhat. Note that the conventions for USB and LSB apply only to the amateur bands. While tuning in military or other utility stations you will have to make s determination of which sideband they are using. Most often aviation related stuff appears to almost always be on USB, as does military ops, but you never know....<br />
With more advanced receivers, there may be a fixed tuned BFO that makes all this a little easier. Some receivers have function switches with USB and LSB that do all that BFO presetting for you. Then all you have to do is peak and tune the Q multiplier to tighten things up.<br />
If you have a Q multiplier that has the " Notch", "Null" or "Reject " position, it will provide you with the ability to eliminate on possible source of interference, such as a strong heterodyne very close to the desired frequency. Tuning is pretty intuitive. Switch to "null" or whatever it is called with your unit, run the selectivity up and tune the Q multiplier tuning to get rid of the undesired signal. The downside of this is you lose the ability to tighten up the overall selectivity of the set up. For this reason I have rarely used the null feature. I am sure there are times that it might be useful.<br />
This is only a very basic primer on Q multiplier operation. As in tuning any other portion of a receiver, it takes practice, practice, practice. Particularly with adjustments for single signal cw operation use of a steady carrier from a standard broadcast station is handy in that it provides a good, stable test signal. For SSB, you pretty much have to work with the real thing. The thing to remember is to get the desired signal in the middle of the passband and set up the BFO to give maximum intelligibility with BFO injection near one edge or the other of the passband.<br />
The most effective Q multiplier/receiver combination I have ever seen is that of the old Drake 2B used with the Drake 2BQ Q multiplier. I have had one for over fifty years and have learned to set it up on cw such that a signal on the other side of zero beat simply does not exist.<br />
The Q multiplier is one device or feature available on some of the older receivers or that might be added. There are also crystal calibrators and preselectors or preamps...we will look at them at another time!<br />
Good hunting!<br />
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DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-20249652817358743632015-10-25T09:20:00.000-05:002015-10-25T09:20:06.727-05:00Books, Books, Books Almost all SWL and Ham shacks have a collection of books that accumulate over the years. I have recently gone through and given my collection a bit of a "haircut" because desk space was becoming limited and some, quite honestly, had not been opened in years. There is some merit in keeping books for historical sense and some for sentimental reasons, but sometimes it gets to be a bit much. Some I simply boxed away, like dozens of old World Radio TV Handbooks that might be of some reference value later, but were just taking up too much room on the shelf. Others have been shared with younger listeners and hams in the area who might learn from them.<br />
But some simply must be kept. High on the list was the very first WRTH I ever had. It was actually a Christmas present from my grandparents.<br />
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This marked a true turning point in DX-ing for me because I had for the first time a list of stations other than those in the magazine columns to help me identify stations other than those on the broadcast band.<br />
Other books that have kept a spot on the shelf include many connected with my career in broadcasting and in amateur radio. Others were obtained to simply learn things or to assist in making repairs to the many radios that crossed my desk as soon as relatives learned I was " playing" with the things.<br />
Engineering books often have good application to hobbies and vice versa. There have been times I have used information from the ARRL Antenna book or the Radio Amateurs Handbook in dealing with problems or designs for projects at broadcast sites. And there have been times that I have used data from the old RCA Antenna Engineering Handbook for amateur antennas in small spaces.<br />
There is of course a move to having more and more books in electronic form. This has its place and one of them is allowing one to keep a larger number of texts in a smaller space. It might also allow some of us to find titles that might otherwise be out of print. But sometimes its good to have an old fashioned book in your lap and to turn the pages.<br />
In any event, whether its full sized books or collections of magazines with radio articles in them, they do find a place in the shack along with the radios!<br />
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DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0tag:blogger.com,1999:blog-1544382238317398005.post-60662446057689736522015-10-11T18:34:00.000-05:002015-10-11T18:34:21.536-05:00New Shack Arrangment After room repairs necessitated by a broken water pipe, there have been some changes to the main operating position. The primary receivers on the lower two rows are the Hallicrafters SX-96 which is very useful for SWBC and BCB DX work To its right is the Hallicrafters SX-111 which is excellent on the amateur bands with great bandspread for an analog receiver and really sharp selectivity with its 50 kilohertz final IF. Because the receiver has a band position for receiving the 10 MHz WWV, with the bandspread available it also provides excellent coverage of the 31 meter SWBC band.<br />
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On the lower row on the left is the Yaesu FT-757-GX with narrow SSB filters that also operate in the AM position and 300 hz CW filter. Then comes the Icom R-75 with 250 Hz cw filters in both IF's and mod for 4 kHz filter that operates in the open or AM position. <br />
To the far right is my old DX standby for over fifty years, the Drake 2B with 2BQ Q-multiplier.<br />
This is a triple conversion receiver with 50 kHz final IF that with the Q-multiplier in operation can really slice! With aux crystal positions filled and using the 40 meter amateur position and one of the ten meter positions filled with a substitute crystal, it can receive SWBC on 60, 49, 41, 31, 25,19 and 16 meters. Even with the analog dial it can provide frequency readout easily to 1 kHz.<br />
DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-16312916738706567112015-10-11T08:11:00.000-05:002015-10-11T08:11:17.370-05:00Medium Wave Seasons Change We have now passed the Autumnal Equinox. Days are getting shorter and nights are getting longer in the Northern Hemisphere, with the opposite happening in the Southern Hemisphere. September 21-22 will mark the equal length days and nights. The hours of grey line prop are changing and for some of us, the hours of optimum prop are shifting through our days.<br />
My time traveling to work is now right at sunrise local time. that means my "mobile DX targets" are becoming available again. In the U-S where many Medium Wave stations change power and directional antenna patterns between day and night interesting things can happen.<br />
While power and pattern change times are supposedly adjusted for the " worst case" interference possibilities, there is some averaging. That means that toward the end of the months in which days are getting shorter, there will be some days when stations are still switching to daytime power while some night time prop is going on. That means the opportunity to hear some stations not usually heard.<br />
At the beginning of a month, there is also another opportunity brought about by errors. Often stations are set up to change power and pattern by timer rather than human switching. If, on the first of the month, someone hasn't reset a timer, power change might come at the time set for the previous month and a few stations may end up on high power or day directional pattern while night prop characteristics are in place. Sometimes if the duty of power and pattern change is left to a morning disk jockey or news announcer, that person might forget about change times coming later and manually change early. While this may result in fifteen minutes or a half hour interference to some stations, it will provide DX opportunities to the alert tuner of the dials.<br />
As these " new signals" appear on the band in the mornings, something else swill be noticed that might not be apparent while tuning the Medium Waves when it is already well dark. Signals at the top of the band will be propping better than those at the bottom. One might not think that there would be that much difference for signals relatively close together in frequency, but when one looks at the percentage of the bandwidth over the frequency itself, the situation becomes more apparent. A 500 kHz spread in frequency over a band at 15 MHz might be only a small percentage but at 1 MHz ( or 1000 KHz) its quite a bit! The D layer that does a lot of the absorbing at MW frequencies is already starting to form, and the frequencies at the bottom or even middle of the band are affected much more than those at the top.<br />
In my drive to work in the morning, this is really apparent as the Chicago stations on 670,720,780 and 890 though all broadcasting non directionally with the same power are often of very different strengths. The lower stations may be very weak as the sun is just rising, while 890 will be stronger. Sometimes the lower ones are inaudible or even covered by other stations from Mexico that are in the same time zone or to the west of me.<br />
Stations from Mexico City provide another such "barometer". Usually stations on 730, 900, 940,1000. 1030,1060 and 1220 from Mexico City are audible here. They are a bit to the East as well as being South of here. Oftentimes the stations on 1000,1060 and 1220 are much stronger than 730 and 900 even though they actually run less power. This situation is the reverse when the path is well in darkness.<br />
Other stations from Mexico show similar characteristics, though the comparison is not really as good because they are from different locations and are different distances. The 1050 ( XEG) from Monterrey will be much stronger than the 540 from San Luis Potosi. The 990 will be stronger than the 540 or 730. The 800 from Juarez ( XEROK) will be much stronger mainly because it is from the West of me by several hundred miles ( I am in Waco, Texas) while the 1570 ( XERF) is always the strongest of all, even an hour after sunrise while in the same time zone. Of course, its is also the closest being just across the border from Del Rio.<br />
At sunrise, conditions seem to change very rapidly. A station that is fairly well audible low on the dial when I leave the house at 1140 GMT might be taking heavy QRM hits or be fading down by the time I get to work at 1200 GMT. Stations high on the dial will still be fairly strong.<br />
Another thing I have noticed this time of the morning. As the sun begins to creep over the horizon, skip on relatively nearby stations gets shorter. Stations like KMOX from St Louis-1120- will come up in strength,sometimes covering a new daytime station in the Austin area that has just signed on for the day. KWKH in Shreveport, Louisiana--1130--will come up above the Mexican station that sometimes dominates the frequency. KCTA in Corpus Christi on 1030 will come up over Mexico City's XEOY.<br />
Just as a note, KCTA is an interesting DX target. They are a Christian station that is day time non directional on 1030 KHz. However, because their dominant station, or the station they must protect, is WBZ in Boston, well to the east, they get to sign on an hour before sunrise Central Time. They also have a presunrise authority of around 250 watts. A DX-er to the West might have a good chance of logging them just before sunrise Texas time if he could null Mexico City. <br />
In addition to the changes as time passes through sunrise, there are also significant changes day to day due to other conditions. In years past, I had sort of assumed that prop in the Medium Wave band was pretty much stable day to day. This thought may have been somewhat reinforced by dealing with construction of stations and being aware of requirements for protection of other stations from interference at night.<br />
However, over the years I have noticed that such is not the case. There can be considerable variance in signal strength from night to night, and particularly during the " grey "hours of dusk and dawn.<br />
It is one thing that I have enjoyed observing as I drive to work each day and even after over fifty years of DX-ing continue to learn. At the same time on consecutive mornings, the same station might have considerable different signals, particularly at the low end of the dial. For example, WIBW on 580 from Topeka, Kansas is a regular here just before sunrise. Some mornings it comes in almost like a local station. Yesterday, however, it was almost covered by a Spanish speaking station. ( probably Piedras Negras) Once XEMU goes to daytime power, Topeka is gone. But with the border station on night power, WIBW usually makes it pretty well, though there can be exceptions.<br />
I have a couple of good barometers for enhanced prop. Two stations from the Dallas area have relatively low power at night but have directional antenna systems that still deliver fair signals to the South and into Waco, KSKY on 660 and KAAM on 770. A quick punch to those frequencies as I start the truck up in the morning ( I have preset buttons for them just for this purpose) will give a good indicator if something is up. If they are in with fairly clear signals, I check the higher part of the band for DX. However, if they are being covered or have signals significantly causing them to "hop", I know there is a chance of hearing something good down low in the band and I can spend the few minutes of driving DX hunting on that part of the dial.<br />
Other good "barometers" are 880 which is usually KVRN from Nebraska with some Mexican QRM and 980 which is usually Kansas City.<br />
The thing to note is that even the medium waves are not the same every day. Things can often change radically from day to day, particularly if there is some kind of major solar activity. Its worth checking your own "barometer" stations daily to get a clue if it worth checking for possible new logs.<br />
An example is the past couple of days ( October 9-11) when there was solar activity that totally mangled the upper HF bands but led to enhancement of MW and LW bands. here in Waco, Texas, a semi-local station ( WTAW 1620 in College Station, Texas 90 miles away) is usually audible day and night, though with some co-channel interference heard at night, usually from radio Rebelde in Cuba. This past Friday night, Rebelde was propping in so strong it completely covered WTAW. You could not even tell it was there! That led to tuning the rest of the band and logging a half dozen new stations.<br />
And finally, I apologize for a lack of posts the past few weeks. We have been making repairs to our home following a water pipe break that flooded part of the house, requiring a replacement of a wall and removing and replacing the flooring in the room where the radios and computer are located. Luckily none of the electronic equipment was damaged, but all had to be moved out and stored during the repairs. Happily all is ( almost) back to normal now and hopefully at least weekly updates will be available from here out. You are invited to scroll back through the archives. Many articles are not time sensitive and hopefully will provide some entertainment if not useful information about a life behind the lighted dials! Good DX.DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com1tag:blogger.com,1999:blog-1544382238317398005.post-61875207801650464742015-09-05T13:51:00.001-05:002015-09-05T13:51:32.173-05:00Record Keeping Part II-Stats One may ask " Why keep stats?" Maybe it is a variation on the idea of collecting things. Maybe its a means of measuring performance or the radios or the antenna-or maybe even the operator! Maybe its a means of learning things about prop, digging out the tough ones. Maybe its for keeping the hobby fresh by always having something new to do in looking for the new ones-a new country, a new country on a given band, new states or grid squares or greater distances. Maybe its for "bragging rights." <br />
In truth, its probably for a bit of all those things. I would suggest that for those who just tune randomly listening to what comes along that setting up a log and a secondary log for keeping stats will open a whole new "freshness" to the hobby and perhaps provide some direction out of the randomness. It will also provide a good way to reflect back on the hobby years or decades later.<br />
The nature of the stat keeping can vary greatly, and if allowed, can grow into almost as big a job as general log keeping itself. I have gone through variations in general log keeping over the years, at times keeping one master log with all entries for all kinds of listening in one log. I am kind of back there now. Everything is kept in a day to day log that is almost a journal of listening.: Shortwave Broadcast, Medium Wave, FM and TV DX, amateur band listening, low frequency non directional beacons, and all forms of utilities. All are logged straight down as they come in the receiver and are identified. <br />
I have also gotten in the habit of logging everything, not just the new things I hear. That is to provide a way to look back and judge band conditions on given days or even weeks or months and get a handle on trends in prop. ( I am still learning the "Black Magic" of it all!)<br />
There have been times when I split out certain types of listening into specialized logs. I would log Medium Wave stations in a separate log, had utility stations in a separate log ( see previous posts) long wave stations in their own and TV DX in its own. There are advantages in that, too. I am now thinking about taking my amateur VHF loggings and splitting them out. Care must be taken in doing this because it can create a lot of work and not a little duplication, but the upside is learning about band conditions and things that create certain kinds of openings. The work involved does pay back dividends in things learned and gives the DX-er something to do on the days when the bands are fully and truly dead or thunderstorms make it an unhealthy proposition to sit in front of a metal box connected to a giant lightning rod outside!<br />
So where should one start? The simplest thing is to start with counting countries. I actually started doing this back in 1958 while doing only Medium Wave DX with my old Watterson five tube table radio. I wasn't even keeping a full listening log then, just a list of stations heard. On a separate sheet, I kept a check list of countries heard.<br />
When shortwave listening began for me with my first home built receiver tuning other than Medium Wave that list began to grow. When I began listening to the amateur bands and later got my amateur license, it grew even more. Soon I began to split the listings into amateur, Medium Wave and All Others. Then the amateur listings split into bands. Then the All Others split into Shortwave Broadcast and Utilities. <br />
This a few years ago during a period of particularly bad weather and remodeling to the house that precluded radio time ( they were all stored away for a time) the time presented itself for going back and "clarifying" all my listings. This might be considered Obsessive-Compulsive by some, but it was a fun way to relive the DX-ing experience over the years and helped deal with the "withdrawal" from being in front of the lighted dials.<br />
In my early amateur operating days, I always listed stations I called unsuccessfully along with the stations that I actually worked. This meant there were lots of stations and not a few countries that could be counted as SWL catches that had not been counted. There was country-count gold there to be mined.<br />
I had already begun using the same ARRL County List charts for tracking amateur countries worked. It was a matter of getting another copy of the chart and adapting it for SWL use. There are numerous ways of determining what is and what is not a DX country or " entity" and there can be some debate over which is " correct". I am not here to join the debate or take one side or the other, but just to report that I happen to have chosen the DXCC list simply because it is at least something to go by.<br />
Some modifications to the list had to be made to adapt it for my purposes. As it stands, the chart has a list of countries in order of prefix assignments, with columns to mark off each entity for the various bands 160-6 meters. I added another column to the left of the entity listings for Medium Wave DX Countries. There were two other columns to the far right of the band columns that were originally labeled " QSL's Sent" and "QSL's Received". I just relabeled them " SWBC" and " Utility"<br />
This "updating" turned into quite a job. Starting at the very beginning, I went through my logs beginning back in 1958 page by page, carefully making down on the "Countries" chart in the appropriate column and line the countries as they appeared in the logs. The entries came from both the purely SWL logs and my amateur logs. Of course from the ham logs, any country actually worked counted as an SWL country on a given band because to have been worked, it had to be heard. And since in those early days, I wrote down the callsign, frequency and signal report information from even the stations heard and unsuccessfully called, there were some other additional countries for the SWL log even if they did not make it as an amateur " worked" station. In those early ham days, my antennas might have been pretty fair for receiving but were in some cases less efficient for transmitting. Also, I had not learned the intricate dance sometimes involved in working a DX station in a heavy pileup, resulting in many good ones heard but not worked.<br />
This sweep of the old logs took some weeks. Some of it was done while watching TV, some at night before drifting off to sleep, some at times when storms precluded getting on the radio, some done while radios were in storage during work on the house, and some time just taken to get it done.<br />
After all the updates to the countries chart had been completed, it was a matter of going down each column and counting the entities in each one. I made up a separate tally sheet to list the tallies for each category: MW, 160,80,40,30,20,17,15,12,10 and 6 meters, with the last two columns for SWBC and Utilities. There was also an entry for overall grand total countries. This number was obtained by once again counting the entry lines of the countries chart, counting each line for which there was any entry at all.<br />
I regret at that time that I did not make a separate breakout for the different SWBC bands. It would have been interesting to see what the results would have been looking at DX performance for the separate 120, 90, 60, 49,41, 31,25,19, 16 and 11 meter bands. Then if I went totally crazy, I could have broken out the utility or maritime bands. Maybe there is such a thing as going too far!<br />
I have mentioned in an earlier post that I wish there were a SWL logging program that would allow doing such. I simply have not found one that is as easy to work with as the basic ham "LOGGER" program, with a simple one line entry. With ham calls, the programs can easily handle dividing things up into entities by looking at the callsign prefix. With SWBC and Utility calls, this is not so easy, but could be handled by the program having an entry column for manually putting in the ITU country prefix or identifier rather than relying on the callsign. <br />
But I digress. After the tally sheet was completed it is now just a simple matter of updating the tally sheet each time I log a new country on a given band. When I make the X-mark in the appropriate column on the ARRL countries chart, I just go to the tally sheet and add one to the appropriate band or category number. I must also remember to add one to the total country total, but only if, in fact, there had been no entry for that entity before.<br />
So how did I come out. Here is the list as it stands today(September 5, 2015) going back to when the first station was written down in January of 1958.<br />
Total Countries: 326<br />
Medium Wave Countries: 26<br />
SWBC Countries: 136<br />
Utility Countries: 84<br />
160 meter amateur: 66<br />
80 meter amateur: 117<br />
40 meter amateur: 210<br />
30 meter amateur: 185<br />
20 meter amateur: 256<br />
17 meter amateur: 177<br />
15 meter amateur: 252<br />
12 meter amateur: 172<br />
10 meter amateur: 215<br />
6 meter amateur: 15<br />
2 meter amateur: 5<br />
NDB/LF BC: 10<br />
TV-DX: 7<br />
FM-DX 4<br />
I must note at this point that I had kept separate logs for two meters, TV, FM and LF/VLF with their own running tallies. Also, all of these tallies are for stations received in Texas and Louisiana. They do not include anything from the days listening from other locations, including the Washington, DC area and overseas locations. I feel they should be counted separately and within their own context.<br />
OK, so these numbers probably don't equal those of the big time, hard core DX-er. But I have never claimed to be one of those. I always figured I was one of the " little guys" who just likes to play with the radios, figuring it keeps me out of the saloons! Besides, its cheaper than a bass boat!!<br />
So is it worth doing all this? Well there is something to be said for doing it for your own satisfaction of seeing an overview of what you have accomplished. For myself, there were some interesting observations to be made when going through logs that covered a year or more in one sweep at a sitting.<br />
It gave an interesting overview of how certain receiver/antenna combinations did at certain locations. One thing that was particularly enlightening was how well I managed to do during a six year span of my life spent living in apartments, using " make do" antennas, often indoors, or in stealth antennas hung around the complex into trees and such and in instances of operating portable.<br />
It was also interesting going through logs against a backdrop of sunspot cycle charts. It showed some amazing catches on 16,15,13,11 and 10 meters on a less than stellar National SW-54 receiver that probably was more a function of the cycle rather than the receiver performance or teen aged operator expertise!<br />
Also, comparing logging times with what I later learned about world time zones, sunrise and sunset times and grey line prop explains a lot about what I was hearing at the time. If I had only had that knowledge then when I had more listening time flexibility during summer school holidays, I might have chosen listening times more carefully and logged a lot more DX!<br />
So what does all this really mean? Probably that careful record keeping is good for providing an overview of your DX career and can provide some real education about how band conditions and prop work. It can also provide some new "fire" for the hobby when conditions or other things drain enthusiasm a bit. And maybe it can provide a little "bragging material" for visits with fellow DX-ers.<br />
Actually, on a serious note related to that last, comparing notes with fellow DX-ers when you have complete records can result in learning a lot about receiver and antenna performance, prop, and even the performance of stations you have both logged.<br />
Hopefully it doesn't just lead to a new outlet for obsessive-compulsive behavior! Perhaps this would be a good time for that old reminder from a friend who will say after a particularly big endeavor: "after all, it is just a hobby". <br />
As always, please share your thoughts through "comments" or provide an email address if you have longer form thoughts to share...and Good DX!<br />
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<br />DX Adventurerhttp://www.blogger.com/profile/17761580261057798315noreply@blogger.com0