The tests yesterday went well enough that I was comfortable getting on the air. So far the GaN FET is holding strong! I think the tweaks to the circuits improved efficiency (around 90% PAE I think) and removed the risk of a 200 amp current surge as it turned off. The Class F portion of the amp is super sensitive to SWR, and it’s windy, so I’m watching my antenna carefully. The Class H envelope-tracking-power-supply-modulating portion appears to have enough bandwidth that my audio is good. That’s a bit of a relief.
Also, the 60V 20A supply I’m using to power the amplifier is super noisy. I have to turn it off to hear anything. But my amp is designed to be a bypass when powered down.
I ordered a lithium polymer battery to run my amp. That should help cut down on the noise. A lot.
Made my first contact, cutting through a pileup on 14.262 (Travis was live streaming)
Update 1: 20 over 9 into the Bay area from Washington State! I’ll take it!
Update 2: Made a good handful of contacts. Audio report was generally good, clean audio. Then I cranked it up another 5% and the FET popped. So back into the garage it goes. I have one FET left. I should probably get some spares. And maybe start a design that will actually get me 1000 watts.
Update 3: Replaced the FET. Sticking to 20 watts in (maybe 400+ watts peak output) and so far it’s happy, through a good hour of conversations
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