Final update:
I received my parts and removed the AOD403 without further incident. That was so easy I decided to go ahead and plop in the new one. I ended up not being satisfied with how it landed and, in trying to remove it to have another go, I ended up lifting the OTHER leg's pad.?
At this point I decided I may be operating a little too far out of my own current skill-level. So I contacted Jeff Moore and shipped the whole thing off.
Jeff found some suspect solder joints, a distorted (by installation heat) power connector, and added the 1N4148 suggested for my 2023 Rev 2 board. He was able to build back up both solder pads for the AOD403, which is now functioning beautifully. In doing diagnostics he noticed some high and flaky SWR readings and spent a few days head-scratching and replacing a few more parts. A lot of labor on a $100 radio!
But last night I was on the air and, despite challenging band conditions, made a QSO with a friend half-way across the country on my simple wire dipole. We gave each other similar signal reports; him running 75 watts and me, well, on the QMX at 12v.??
Thanks to John for your diagnostic help and encouragement. Thank you Jeff for doing top-notch work and providing an accessible backstop when I finally acknowledged I was out of my tinkering league!?
Two other notes:
Using my device for CW practice, in practice mode, with a QRP-Labs dummy load, it had a terrible thump that made it mostly unusable for that purpose. On the air with a real antenna that thump completely disappeared and it is extremely well-behaved. Ironically, Hans pushed out several firmware improvements while I was without my unit, and v.16 -- with the fixed CW algorithms, was released the day I got it back.
And today comes yet more new firmware with AGC. Wow. I feel like Hans has really cornered the market on a usable, portable, affordable, and uniquely feature-ful QRP transceiver. Brilliant!?
Todd W2TEF