Wednesday, March 17, 2021

What Is a Typical Weekend on the Radio for the DX Adventurer

 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.

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."

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!!

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.

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."

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.

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.

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.

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.

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.

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?

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.  

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.

Good DX!

Sunday, March 14, 2021

Tuning the Ham Bands with Analog Dial Boat Anchors


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. 

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")

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.

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.

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.
                                                       Hallicrafters SX-71 bandspread dial

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.

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.

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.

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.

                                                      Hallicrafters SX-96 bandspread dial

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.

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!!!)

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.
Many of the radios that do have calibrated bandspread for the ham bands also have a 0-100 band spread for use on SWBC.


                                                     Hallicrafters S-118 dial


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.

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.
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!

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.


Thursday, March 11, 2021

Tuning a DX Contest With the Knight SpanMaster--a REAL adventure

 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.

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.

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.

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.

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. 

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.  

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.

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.

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.

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.

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!!

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.

( 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!)

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!

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.

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.

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.

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.

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!

Finally at 0030 GMT, I copied his callsign: EA3F  Spain!  There was hope this would not be a waste of time!

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.

( 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)

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.

It was a tough several minutes after that, but at 0113 another station from Spain, EA4W, was logged.
Then three minutes later CR6X from Portugal ( don't get overwhelmed by this high logging rate now!!)

It was eight minutes after that when LZ9W from Bulgaria was pulled out.

And that was kind of how it went into the evening...sometimes three or four minutes between loggings,  sometimes more.

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.

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.

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.

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.

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.

I shut down at 0400 with the plan to get up the next morning to see if any Asians could be heard.

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?

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!

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. 

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. 

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.

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.

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.

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?

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.  

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!!!" 

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."

Tuesday, March 9, 2021

DX-ing With the Knight SpanMaster

 

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.

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?

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.

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.  

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.

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.

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.

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.

Soon it was ready to come to its new home.


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. 

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. 

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.

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.

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!


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.


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?

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.

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. 

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.

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!


Monday, March 8, 2021

The Annual Coastal DX Trip

 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.

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)

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.

This year the trip had to be rescheduled twice because of  hurricanes.

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.

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.

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.

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,

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.

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.

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.

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.

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!

The water path to New Orleans was excellant with the mid afternoon signal from WWL on 870 booming in at well over S-9.

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 .  

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.

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.

Unfortunately packing to leave the next morning had already begun and there was little time for last minute DX-ing.

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.

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.

Oh well,  there will be other trips and other times.

Such is the world of DX.