traced the board

Started tracing. Tried to find the fault. Immediately I found the power switch was not working! What?! Or at least the pole I used didn't work. Shorted the switch. No LED. Damn. Wait... a sound. The motor! The motor was turning, clockwise, in fact. Holy cow. It did work. Dialled the speed up and down. Yes. The barn door tracker control circuit was working... partly. Tried the N-S switch—stopped. OK, I was not out of the woods yet but I was very happy with my progress. It was not a catastrophic fault. Perhaps a simple matter on one side of the hemispheric circuit...

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Other continuity tests, further downstream yielded peculiar results. I must have a short, I thought...

Then I found a dead resistor. Yes, a dead resistor. The 470 ohm for the LED. No continuity! How the heck does a resistor fail? Readied to swap it out.

I was discouraged. I decided to sleep on it...