Well, the Black Friday Fairy brought me the prototype Project Egbert hardware. It's only a little more than 40 days and 40 nights since I released the design. And the overall product deadline doesn't seem to have moved any, of course.
Working through it in stages. It passed the first-stage smoke test (the power section works OK). Got some high-frequency switching noise, but that should get filtered out by the ferrite beads that, when installed, will connect the power-supply outputs to the rest of the board.
Back to work now. Busy afternoon, busy weekend....
Update: got some smoke out of it. I cobbled a circuit on the back to replace a chip that's become unavailable (I'm pretty sure it was in stock back in July, but by October supplies had evaporated, and the manufacturer is currently showing a 16-week lead time), and my attempt at hand-wiring the circuit, including a SOT-23-5 chip and other small fiddlies, was less than successful. That's enough for today. Tomorrow, I'll try another (temporary) workaround that doesn't involve such delicate kludgery.
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