DC AUDIO D9

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This amp came to me with 4 shortened output mosfets, and a damaged driver board.
I replaced the 4 mosfets and driver board with brand new board. I also
pulled out all the rectifiers to power the amp On, and it powered without any problems, how ever, when I test the signals at the gate of the output mosfets nothing shows. Do I need to have the rectifiers solder back In to get a signal at the output gates?
 

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No, there's no signal with the 10k resistor in place, but again I lost signal at driver board input pin.
All regulators -15; +15; -5 and + 5 are all ok.
Pin 1, 7, and 8 of IC 102 have signal, but there's no signal coming out of pin 14, so
I replaced IC102 (TL074) and no good result. Any idea?
 
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Without the rectifier there's no signal at the driver input pin, but with the rectifiers solder in
There is signal going into the driver board and signal on all 4 low sides out of the driver board. ls this normal for this amp?
Also I tried to force the high side signal out using 12 volts between pin 11 and 13, but could not get the high signal to come out.
 
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I couldn't trace it back to far, but with the rectifier out, the signal doesn't make it to the driver boar input pin.
The signal goes as fallow.
IC 101, pin 1 and pin 7 good signal same amplitude , pin 8 good signal some amplitude, pin pin 14 good signal some more amplitude.
IC202 pin 1 or 7 no signal.
IC203 signal is coming out at pin 1 with clipping at the button, and pin 7 with clipping at the top.
IC102 pin 1, 7 and 8 good signal same amplitude. Pin 8 no signal.
IC103 pin 1, 7 and 8 good signal same amplitude, pin 8 good signal some amplitude.
 
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A customer brought me another identical model amp with a bad power supply, so a repaired the power supply and tested the amp. After it was tested and working, I took the rectifiers out and test the signal at the driver board input, and to my surprise, there was no signal.
I Don't know why, but this amp can not be tested without rectifier in the circuit.
I'd put back together the original amp that was giving me problems, and it was working perfectly.
In the past, I tested very similar amps without the rectifier soldered in and got good result, but not these D9.
Does anybody knows why this amp can not be test it without the rectifier in the circuit? Thank you for all the help.
 
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