Need tech help: dead Arion SCH-1


I found an SCH-1 chorus in a shop - the depth pot was faulty when I tested it but everything else worked great. They happened to have an extra SCH-1 board laying around for parts, so they swapped the pot out, and sold it to me for cheap...and they threw in the parts board. I got it home and the whole pedal was DOA, so they refunded me and said just keep everything!

So now I'm not getting any power from battery nor power supply. I do get a bypassed guitar signal, but pressing the switch does nothing. I tried swapping out the protection diode (D1), no luck. Is it the switch? It was fine when I originally tested the pedal. Or did they fry something when they swapped the pot?

I've got an entire extra parts board to work with, including the bbd chips, so let the tinkering begin haha.
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Nuzzled Firmly Betwixt
Platinum Supporting Member
After checking the switch and any associated circuitry:

a) do you have an ammeter? Specifically, can you measure current with it?
If so, connect a battery on one terminal, and place your meter inline. Measure the current.

b) do you have an oscilloscope? You could look for clocks on the proper pins of the BBDs

c) Do you have a method for injecting a signal? If so, you could separately test the output stage, the input to the BBD, etc.

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