Heatsinks and IRF510s arrive

My heatsinks and more IRF510s have arrived in the post today. All being well I'll get these into my 136kHz QRSS3 beacon and transverter shortly and be back in business by the weekend, although operating time will be limited because my elder grandson is staying and sleeping in the shack.

Blown my 500kHz PA ......again

My IRF510 500kHz PA has a tiny heatsink (soon to be addressed when a new heatsink arrives) and it is not very tolerant of poor antenna match. As a result it died again this evening in mid WSPR! This afternoon I managed to raise to PA output to 8W by changing values and this must have made the tiny heatsink just too small to be useable. I also need to find a better way of getting my antenna tuned to 50 ohms.  This is all a good excuse to do a proper rebuild next week.

5W (from the PA) on 500kHz

With the arrival of some IRF510 FETs I've built a small PA to go on the end of my WSPR beacon transverter. The output (from the PA) is now 5W, so my ERP should be up by around 10dB to around 50-60uW. Already I have been spotted by G7NKS some 10dB stronger than ever before - most encouraging!