2 Dec 2009

Back on 500kHz WSPR (TX)

Having just got some more IRF510 FETs from the GQRP club I've rebuilt my 500kHz PA and got it working properly towards class E. As long as the antenna is close to 50 ohms the PA hardly gets warm (on a WSPR TX cycle at 5W RF from the PA) as the efficiency is now so good.

Will run the 500kHz WSPR beacon overnight tonight then plan to modify the PA and ATU to 136kHz for a few days. 136kHz WSPR tests will run over the weekend if things go to plan. ERP will be even lower than on 500kHz, but I'm hopeful of some reports. If you get a chance to listen and report (via the WSPR database) I'd be most grateful.

The new TX PA is working well: I've had a 0dB S/N WSPR report from F6CNI near Paris!

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