Wow, Paul Taylor, VK3HN is working on homebrew rig #11. FB.
This interview was quite thought-provoking.
-- I agree with Paul about the importance of not being dogmatic about
always staying under 5 watts. It sounds like Paul is having fun with his
100 watt SOTA project.
-- It was great to hear that Leon VK2DOB is still active in ham radio and running a QRP company in VK. FB. An article by Leon on CMOS mixers in the summer 1999 issue of SPRAT played a key role in my understanding how switching mixers really work. I put Leon's diagram in my book SolderSmoke -- Global Adventures in Wireless Electronics.
-- On blowing up the finals in simple HB gear. The first real transmitter that I built was the VXO-controlled 6 watter from QRP Classics by the ARRL. It had a 36 volt Zener diode across the collectors of the final. This was to prevent the kind of final destruction Paul suffered up on that summit: "D2 is used to clamp the collector voltage waveform to protect the output transistors if the transmitter is operated into an open circuit or high SWR antenna system." Maybe we should revive the use of that simple SWR protection circuit, especially for SOTA rigs.
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