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I've only seen the plastic-enclosed PCB relays installed on those SVTx-Pro amps. Since you don't have any DC issues on the two channels now, you'll have to trouble-shoot the circuits. Both are sharing the Neg reference voltage (-15V thru a 22k resistor R171 & diode to ground, D120), with each channels' comparator input having a 15k resistor tapping the neg reference voltage string at D120 cathode/R171. With 0V at the inputs (diode-connected to the time-delay circuits of 220k and 22uF NP cap to Gnd, you'd get negative output from the comparator, which will turn on the MPS A56 to pull in the relay. See if you have negative voltage at the two comparator's (+) inputs would be a place to start.
What's in the photo looks like someone may have pulled the cases off to address the contacts, instead of replacing them? Seemed like they were electronically welded closed.
What's in the photo looks like someone may have pulled the cases off to address the contacts, instead of replacing them? Seemed like they were electronically welded closed.
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