Tuesday, July 28, 2009

PSK31 contacts

Today I thought I'd try to make some PSK31 contacts using the QRP Wonder Loop. Because the mouse pointers go berserk on both of my laptops when in the presence of a strong RF field, I had to use the main shack computer and therefore the K3. But I turned down the power to 5W p.e.p, which is what I would run if I was using the FT-817 or the K2, although the tuning capacitor I used could easily handle 10W, and perhaps even more.

The picture shows the map displayed by Propagation Reporter after I had been on the air for three hours or so on 20 metres during the late morning and early afternoon. For those unfamiliar with the display, the small markers show the stations that had been received on the Wonder Loop and decoded by Fldigi. The large markers with a time interval show the location of stations that heard my transmissions, and how long ago they last reported me. These stations would have needed to receive "DE G4ILO G4ILO" without errors in order for their software to submit a report, so the large markers represent stations with whom it would have been possible to have a QSO. The concentration of large markers in Western Europe may in part be due to the fact that fewer people in Eastern Europe have a broadband internet connection, without which propagation reporting is not very practical.

It has been more than a year since I last operated QRP PSK31. I got the 100W PA for my K3 because I was starting to find QRP a bit frustrating after the many years (it seems!) of poor conditions. So I had forgotten that PSK31 with 5W can be a bit hard going.

I called CQ most of the time because that gives the best chance of being spotted on the Propagation Reporter network. Although a couple of dozen stations heard me (as you can see from the map) only two replied to my CQs. I made one other contact, with DB7HH, which was in reply to his CQ. Normally when working QRP I would search out other stations and call them, which would probably have resulted in more contacts.

I think the Wonder Loop performed well in this test. I think the difficulty in making contacts was mainly due to the poor conditions. There were no really strong signals during the period of the test. Although the results might not show it, I felt that the loop worked well enough that it would not be too bad if it was the only antenna I had. In fact, it's working better than I expected.

1 comment:

PE4BAS, Bas said...

I would say exceptional performance for such a small antenna with only 5W. If I had some time left I would like to make a sked with you to test. It should be possible to make a QSO as I see where you've been received.