Sunday, August 9, 2015

When Sunspots Fade

        As anyone knows who has tuned the bands for any significant amount of time, the fate of our loggings is in the "hands" of the sun.  Sunspot activity results in the higher bands being open more. The Maximum Useable Frequency becomes higher and for reasons known only to the physicists, the higher bands seem to be more amenable to sending lower powered signals very easily.
       We are currently on the downside of the eleven year sunspot cycle and the days of bands up to and above 30 MHz being open are rapidly fading.  For those of us in the U-S that means the higher bands may be open, but for shorter distances and for more limited times of the day. Signals on the 13 and 16 meter shortwave broadcast bands are almost non-existent.  On the amateur bands, little or nothing is being heard  ten and twelve meters, sometimes little on fifteen.
       Such was the case when I tuned the bands this past Saturday morning ( August 8, 2015 at 2300 GMT)  I had planned to look for  some DX and get a little intense cw copying practice listening in on the Worked All Europe contest. I heard nothing at all on ten meters or fifteen and only stateside signals on 20.  Checking a little later in the morning about 1800 GMT there was one station audible calling CQ with no takers on ten meter cw.
"Wake me when the band is open", (C1AT-second op)
       At this point I figured it was time to make a swing of the WWV frequencies and see if any kind of trend could be determined there. On 25 MHz, the stateside WWV was in at S-5 and steady, 20 MHz was S-9 and steady, 15 MHz was S-9 and steady and 10 MHz was S-9 + 10db.  Nothing was audible on 5 or  2.5 and there was no sign of WWVH coming into Central Texas.
        Going back to fifteen meters resulted in a number of strong stateside stations being heard  with a second tier of weaker stations distributed among them. The strong stations were apparently first hop deals, while the weaker stations were generally from Europe.   This was a case where the opposite of the usual tactic is taken.  Instead of tuning in the wide bandwidth mode and tightening down when a desired station is found, this situation calls for tuning in the narrowest mode to begin with to prevent the much stronger stations from washing over the weaker ones  It requires very slow tuning and careful listening.  When doing this I often tune up one kHz, then back a half, then back up one, etc.
        In this case, several European stations were pulled out that were "just over the grass".  While many US stations were S-9 and well above, most of the Europeans were S-5 and under. A quick tune across the band in the wider band modes might have given the impression that there was no DX at all to be had.  Once again, patience is the key to this hobby,  much as it is with fishing!
       Another method for logging DX stations in a contest when conditions are less than optimal also requires patience, but of another kind.  You can find a US station calling CQ contest and park on his frequency waiting for stations to show up.  Often the nearby station may be weak or fluttery sounding.  You may have to listen for an extended period of time to get a good one, but often the wait is worth it.  If the band is marginally open, a run of stations by your target will also indicate the band is getting better and that it might be  "safe" to start random tuning across the band. Of course this applies only to those SWL-ing the contests. Those operating an amateur station and transmitting plays a different game altogether.
       Finding a station as a "lure" that is more attractive to Europeans or other DX in such a situation can improve your chances greatly.  For example, here in Texas I will look for a KP4, KP2, PJ4, FM5, or some other Caribbean station that would be more attractive to the DX than a W2 or W5 and park on them for awhile.
       This  particular Saturday, these methods did turn up a few DX stations on fifteen meters,  but it soon became obvious that the band was not really hot or that many stations just were not spending time there but hanging out on other bands where higher QSO rates might be found. So the next step was to try the next lower band, which was twenty meters.
       After a break for lunch, surely enough, a little more activity was found on twenty meters. A similar situation was found on twenty as was found on fifteen earlier, but the "second tier stations" were a bit stronger and a little easier to pull "out of the crowd".  In this case, the first hop stateside stations were S-9 and above, while the Europeans were about S-7 or so, occasionally topping S-9. The ratio of DX to stateside stations was better, also...almost half and half as opposed to one out ten on fifteen meters a couple hours earlier.
       Interestingly, later into the evening when one would have thought things would decline with darkness, things actually picked up on twenty meters.  I can't help wondering if it was because of the long summer days in the polar regions because most of the signals were Russians and Swedish stations,  with a sprinkling of Asiatic Russians. Signals from them to Texas would be taking the polar route.
        But the real telling of the tale came later in the evening, after dark Texas time.  At 0300 GMT August 9, I made the move to forty meters.  It made me wish I had gone down there much sooner. This was where the gold was hiding. Here the European stations were stronger than the US stations.  Some HB9, S50, YO and Italian stations were S-9 +10-20db! This was more like it! The DX stations were not only stronger than the stateside stations but outnumbered them about three to one!
        After several years of very good band conditions and a couple of years of slowly declining conditions, the situation where a change in tactics was required caught me a little by surprise after all my years of listening.  I should have immediately gone to the lower bands.  When the sun's activity begins to wane, it doesn't mean the DX goes away.  It just means that it is found in different places. 
It means spending time on the lower bands, and because those bands are often rendered less useful during high sun times because of absorption in the  D layer of the ionosphere, it means a shifting in time spent in front of the radios.
       The lower bands, while best after dark or with the path between transmitter and receiver mostly in darkness, can indeed show some life in partial daylight.  The thirty and forty meter amateur bands and the 31 , 41 and 49 meter shortwave broadcast bands can bring some amazing results as much as two hours before sunset and two hours after sunrise. The lower bands, meaning the 80 and 160 meter amateur bands and the 60, 90 and 120 meter shortwave broadcast bands might not show quite so much life before the sun goes down.
        One other consideration for finding good DX on the lower bands is the antenna.  While a short wire antenna will give some results,  the really good stuff will show much better signal strength if the antenna is responsive to lower angle arriving signals.  While this is probably much more important on transmit,  once you have seen the difference in strength of signals with an antenna with good low angle response you will never forget it.  Not only are the signals stronger from the DX, but the QRM from closer in stations will be less because the antenna will discriminate against the higher angle arriving signals.
         Antennas for receive do not necessarily have to be resonant with the sensitivity of most modern receivers,  but everything helps.  If you have a horizontal antenna only fifty or less feet long and only up about twenty feet, don't expect to hear the really weak signals on the lower bands.  The difference is actually phenomenal.  The only way to get good long angle response if you cannot get really good height on eighty and 160 meters is to have a vertical or inverted L antenna.  Even on forty meters, a flat top dipole would need to be 66 feet high to be optimal.  That is not to say something lower won't will hear things,  just not as easily or as often.  You won't "open the band" often. 
       The maximum current in an antenna fed against ground is a quarter wave back from the distant end. That is where the most " work is done". If you can't get more than thirty or so feet up,  the best thing to do is get as much wire vertical as you can and run the remainder out horizontally,  making the classic inverted "L". The idea is to get that high current part in the vertical section to get a good low angle response. Top fed slopers where the center of the coax goes to a wire suspended from a metal mast or tower with the shield going to the metal support will work, too.  The wire then slopes down toward the ground, hopefully at an angle 60 degrees or better...though anything greater than 45 degrees will work. That will get the high current part even higher off the ground and reduce losses in things cluttering up the RF space in your yard.
       Again,  as the sunspot activity declines even more,  you will find the lower bands getting better and better and the higher bands showing less and less life, with their windows of time being shorter when they are open.
       I have found this to be a cycle that has gone through my hobby over the last fifty-plus years of playing with the radios. This will be the fifth time.  The thing to keep in mind is that its not a loss of band activity, but a shift in band activity.  The only negative is that the time of day is shifted,  just like the time of day shifts for fishing in hot weather. Its an eleven year cycle that we just have to live with.
       Just when I thought I was finished,  I remembered something else I need to add.  Don't completely write the upper bands off.  Check Space Weather from time to time or sign up for alerts about solar storms or Coronal Mass Ejections.  Remember that when those things hit, be ready to check the upper bands shortly after the event,  because as things  "settle back down" there will be a short period of time when the ionosphere will see that little extra ionization that it would otherwise get from higher sunspot activity.  You would not want to miss an opportunity of some "gift" openings of the high bands!.
       I still will continue to make quick checks of the bands from "the top down" when I first turn on the radio.  And I always run the WWV frequencies to get a feel for how things look-particularly for situations when WWVH  is stronger into Texas than WWV is ( happens more often than you might think) It gives a good indicator of openings over the Pacific. For those in other parts of the world,  I am sure you can find other such markers that can give you an indication of what is going on.
       In any event, as things change, shift with it.  Its just a matter of knowing when and where  to "drop the hook into the water"!  
       Good DX!


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