Some good news – my spare U600 is good, but the jitter was still present with the swap. I also swapped out the switch, U400, with no change. At least I know I have some good spares.
I put the originals back in, with the jitter still present. I had other things to do.
Came back a few hours later – no jitter. I let it run for a while – no jitter. Put it back in the case, let it set for a while, and turned it back on. No jitter.
You know what they say about problems that fix themselves.
I’ll try it out again in the morning.
Thanks for the advice on inserting the IC’s – I made sure they were seated properly before putting on the nuts.
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