As of now, when the transistor that was driving it into protect is out of the circuit, do you have drive into the driver ICs?
Do you have output from any of the 4 output drive channels of the 2 ICs?
Do you have output from any of the 4 output drive channels of the 2 ICs?
If you bridge pins 1 and 2 of IC12 with a meter probe while monitoring pin 1 of the driver IC, does that bridge give you a signal (whatever you're driving into the amp) at the input of the driver IC?
I have 7.8v DC on both of those pins but solid DC, I don't see any audio signal if that's what you're asking
Are you driving a signal into the amp?
Do you see audio on the output pins of any of the op-amps in the preamp section?
Do you see audio on the output pins of any of the op-amps in the preamp section?
Update: Took a break from this amp for a little while clear my head of it.
Sending a 40hz sine wave through input rcas I see audio signal on pin 1 of IC2 and IC4.
IC2 and IC4 still aren't sending PWM on output pins. LM319, IC2, and IC4 replaced.
As soon as I send audio signal through the amp it goes into protect.
D33 and R157 still throw amp into protect regardless of signal input so all testing has been done with them pulled.
Sending a 40hz sine wave through input rcas I see audio signal on pin 1 of IC2 and IC4.
IC2 and IC4 still aren't sending PWM on output pins. LM319, IC2, and IC4 replaced.
As soon as I send audio signal through the amp it goes into protect.
D33 and R157 still throw amp into protect regardless of signal input so all testing has been done with them pulled.
Is this what you have:
Pin #:
1: square wave input
3: 5v
4: input ground, placement of black probe when measuring voltage on pins in this group.
5: near ground
8: 5v
9: black meter probe
11: 12v
14: black meter probe
16: 12-15v
Pin #:
1: square wave input
3: 5v
4: input ground, placement of black probe when measuring voltage on pins in this group.
5: near ground
8: 5v
9: black meter probe
11: 12v
14: black meter probe
16: 12-15v
Updated correct measurements
Pin #:
1: square wave input
3: 5v
4: input ground, placement of black probe when measuring voltage on pins in this group.
5: near ground
8: 5.01v
9: black meter probe
11: 15.17v
14: black meter probe
16: 2.4v
Pin #:
1: square wave input
3: 5v
4: input ground, placement of black probe when measuring voltage on pins in this group.
5: near ground
8: 5.01v
9: black meter probe
11: 15.17v
14: black meter probe
16: 2.4v
With black probe grounded to pin 4 I see 15v on pin 16. I'm thinking something might be backfeeding to pin 14