Amateur radio: North American QSO Party, SSB

I’ve been spending a lot of time coming up with a good way of motorizing the tuning shaft of the vacuum variable capacitor, and make the whole assembly modular so I can move it from one loop antenna to another to optimize a particular band.  I only ended up using one antenna during the 12-hour NA QSO Party on Saturday, but it generally went pretty well.

The main problem was getting the very top-heavy antenna in the air!  In fact, at one point the PVC mast ended up bending down several feet and I all I could do was guide it to the ground so that the capacitor/motor box would land gently.  However, I had to bend the 15 feet of 1/4″ copper tubing of the loop back into a roundish shape.  Thus I only ended up barely getting the top of the antenna much above 10 feet.

Once I got that up and started working, the big problem was that it is annoying and time consuming to tune up the antenna by working the motor.  That requires switching the antenna over to the miniVNA Pro so I can see the the narrow SWR peak and move it to the desired frequency.  It’s not too bad on 20 meters, but is only about half as wide at 40 meters, so you can’t flip around all over the band and respond to CQs.  It’s narrow enough that I’m not sure that any indirect method (i.e., using motor position) will work optimally.

One other issue was that the optimum position of the coupling loop seemed to change between bands, which meant tweaking that several times.  This is a big deal because when you already have very narrow 3:1 SWR bandwidth of 10s of kHz even with a 1.0:1 peak, you can’t work much if the peak is already above 2:1!

In any case, when everything was working, I was doing pretty well.  I’m still doing search & pounce only, so no big number of QSOs.  However, I felt that system was in good enough shape to run 30W then 50W, as opposed to my 5W QRP in the previous two contests.  Plus, this contest has a power limit of 100W, so I was running enough power so that if I could hear them, they could usually hear me.  I almost never had to repeat anything, and only had one marginal QSO due to fading.  Of course, it still took a lot of work to get through some pileups.

Th highlight was working Costa Rica on 20 meters, my first non-US mainland QSO!  I did hear a few VE calls responding to the same CQs I was trying to work, but made no Canadian contacts.  I made 9 QSOs on 20 meters before switching to 40 meters near local sunset.  Another 18 QSOs, including one out to the east coast (MD).  I tried 80 meters a few times, but 1) the efficiency of my loop is probably down to nearly 1% in that band; 2) there was a lot of noise; and 3) all I heard was the usual rag chewing and no contesters.

Although I did work 6 California stations, I heard several more at S9 or S9+10 but was never able to get a rise out of them.  They may have been running separate RX/TX antennas and the former were more directional, or for some reason I just couldn’t get through the other calls.

There were a lot of very good operators and in particular I was impressed by an operator in MS that I just couldn’t get through to.  He was working like crazy, but was obviously dealing with constant pileups and noisy conditions from severe thunderstorms not that far away from his QTH.  It was a very friendly atmosphere overall.

I really need to come up with a good way to get this antenna up and down easily and safely, as well as hold it up.  I knew this was going to be a problem with being so top-heavy, but there was a snowstorm the day before (and day after) the contest, so I didn’t have time to work on that.





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