Day counter air core inductor calculator
Well there have also been occasions when I have wanted to QSO with a particular station, at a particular time, and have been unable to because conditions didn't quite allow it with my QRP power, and I have wished I had a bit more in reserve. All with humble equipment and mediocre (being generous!) operating skills. I am sure many of you have experienced this too. and they don't even know my very low power until I tell them, then imagine their surprise. I can work stations running 300W, 500W, 600W. Or call a CQ using the programmed message feature of my QCX and someone will answer within a few minutes. I know that I can switch on my 20m or 40m QCX CW radio at any time of day or night (respectively) and within a few moments, I can work someone on CW.
Until now, I have never had a QSO with more than 5W in my life. Why oh why QRO? Blasphemy!? This is a very good question. and remember to CLICK THE PHOTOS for bigger versions. Speaking of which - a significant number of MOSFETs were not so lucky and met untimely and explosive endings. Yes this is clear abuse of a 20W dummy load but my key-down periods were kept somewhat brief and the dummy load appears to have survived unscathed. A 35W single-ended, single IRF510 amplifierĪs well as the junk box, other equipment used includes a 30V 5W variable lab power supply 12V homebrew power supply (12V 5A, 5V 5V all regulated) a big old 50V 20A power supply (ex-BBC) oscilloscope DVM and a QRP Labs 20W Dummy Load kit.A very nice Low Pass Filter made with wooden formers.In summary, the results of this effort were: All experiments so far, were limited to 40m. Therefore this is an interesting story of scrounging as well as simple RF amplifier design. All components were sourced from the junk box. Here begins a somewhat questionable quest to amplify the output of a 40m QCX 5W CW transceiver kit to 50W.