With the amp powering on and no output, where should I start, there no shorts in the fets or bjt's or rectifiers.
Do all of the op-amps have ±15v on their power supply terminals?
Do all of the output transistors have ±rail voltage?
When driving a strong signal into the amp, do you see audio on the output terminals of all of the op-amps?
Do any of the op-amps have more than a fraction of a volt of DC on their output terminals?
Do all of the output transistors have ±rail voltage?
When driving a strong signal into the amp, do you see audio on the output terminals of all of the op-amps?
Do any of the op-amps have more than a fraction of a volt of DC on their output terminals?
Datasheet shows pin 8+ and 4- correct? if so there's nothing on 8, no rail voltage. 1/7 of the op amps show nothing with 60hz signal. No power at all on the op amps outputs.
I don't know this amp but in virtually every amplifier, if pin 4 has -15v, pin 8 should have +15. Find the voltage regulators and troubleshoot from there.
Hi Perry, so I bought an identical 36401 that works. When I tested bjt's have rail voltage +/-23, when I took it out of the heat sink I lost rail voltage. So that got me thinking, I put the old one back in its heat sink and rail voltage good, op amps +/-14. So im not sure why none of that would work unless it was in the heat sink? So still no audio on the old obviously but I feel like im back in the game on this one.
the input ground on the amp power/ground terminal. I ran a 60hz signal through the rca, I see it on the speaker output but still no sound.
Place the black meter probe on one of the non-bridging speaker terminals and measure the voltage again.
Ok, again im not sure if my scope is set wrong. I have it set to auto and Vpp but all I see is like 0.00003 volts on the non bridged and 0.4 on the bridged.
The non-bridging terminals are a reference (black meter probe) that you will use to check the secondary voltages.
The different reference was for it out of the heatsink. Does the different reference make a difference out of the heatsink?
If you measure from the center terminal of a positive rectifier to the center leg the adjacent negative rectifier, what's the DCV (out of the heatsink)?
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With the black meter probe on one of the non-bridging speaker terminals and the red on either of those points, you read 6.83v?