With no power applied, what's the resistance from the RCA shields to the positive power supply pins for the op-amps?
What is the DC voltage on all 3 legs of each regulator with the black probe on the non-bridging speaker terminals?
The regs should be fed by the rail voltage. Do you have only 11v of rail with the regulators in the circuit?
D32 is a Zenner diode. Across it its measuring 650ohms. Diode check beeps both ways and measures 0.438 on my Fluke 16
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It's a regular diode, not a zener.
You'll have to desolder one leg because it's in parallel with a 665 ohm resistor.
You'll have to desolder one leg because it's in parallel with a 665 ohm resistor.
^ As tested^
The amp tries to power up but only for about a second; I see 80v across rail but it almost immediately drops and falls. Its like its going into protection but the protect light isn't lighting up.
Like as soon as the LM337 sees voltage the amp then must be shutting down somehow.
The amp tries to power up but only for about a second; I see 80v across rail but it almost immediately drops and falls. Its like its going into protection but the protect light isn't lighting up.
Like as soon as the LM337 sees voltage the amp then must be shutting down somehow.
Pull D15 and D21. Reinstall the 317. If the amp will power up, post the DC voltage on all 3 legs of each regulator.
U5
1: 16.9
2: 18.1
3: 41.7
U6
1: -15.6
2: -42
3: -16.8
Those diodes might be bad. Only checking in at 0.215 each. What are they?
Goodnight! Thank you so far
1: 16.9
2: 18.1
3: 41.7
U6
1: -15.6
2: -42
3: -16.8
Those diodes might be bad. Only checking in at 0.215 each. What are they?
Goodnight! Thank you so far
The .215 is OK. Those are Schottky diodes.
Is the voltage (without the diodes) 0v on the power supply pins of the op-amps?
Is the voltage (without the diodes) 0v on the power supply pins of the op-amps?
I think so. I did check and the outputs all went to basically zero. I think the power pins too. I’ll check again in the morning to confirm though.
Do you have an incandescent light bulb (110v, 60ish watts) that you could insert in place of D15?