There's not much you can do with the outputs out of the circuit.
If all channels are having problems now, check the voltage regulators.
There's really no reason for you to read anything other than OL from the gate to source. The two drivers aren't biased on so they can't (shouldn't) conduct and there is no pulldown resistor on the gate so OL is likely what you're supposed to read. 13M is insignificant in almost any circuit in car audio amps.
If all channels are having problems now, check the voltage regulators.
There's really no reason for you to read anything other than OL from the gate to source. The two drivers aren't biased on so they can't (shouldn't) conduct and there is no pulldown resistor on the gate so OL is likely what you're supposed to read. 13M is insignificant in almost any circuit in car audio amps.
Ok makes sense. The voltage regulators had solder on the legs and looked to be transplanted from another amp. I replaced the voltage regulators and the rectifiers for good measure.
When measuring voltage on the gate and source pads with no outputs installed shouldnt I have +36 vdc on the 9540 gate and source pads and -36 vdc on the 540 gate and source pads?
When measuring voltage on the gate and source pads with no outputs installed shouldnt I have +36 vdc on the 9540 gate and source pads and -36 vdc on the 540 gate and source pads?
I checked all the solder pads on every output in all channels no outputs installed.
Every single source pad had -/+ 36 vdc and every gate pad had +/- 33 vdc. All the drains read 0.000 vdc.
The only pads that were different were the Q110 and Q123 pads. They read as follows:
Q110
G: -8.50 vdc
D: 0.000 vdc
S: -36.00 vdc
Q123
G: -8.50 vdc
D: 0.000 vdc
S: -36.00 vdc
Why or what would cause the gate pads of these 2 fets to only get -8.50 vdc?
This must be the problem somewhere in the gate circuit.
All these measurements were taken with black probe on amp ground and all Qx105 and Qx106 installed.
Every single source pad had -/+ 36 vdc and every gate pad had +/- 33 vdc. All the drains read 0.000 vdc.
The only pads that were different were the Q110 and Q123 pads. They read as follows:
Q110
G: -8.50 vdc
D: 0.000 vdc
S: -36.00 vdc
Q123
G: -8.50 vdc
D: 0.000 vdc
S: -36.00 vdc
Why or what would cause the gate pads of these 2 fets to only get -8.50 vdc?
This must be the problem somewhere in the gate circuit.
All these measurements were taken with black probe on amp ground and all Qx105 and Qx106 installed.
These FETs are defective. If the gate voltage is 20v above the source voltage, the drain should be at of VERY near the source voltage.
If the FETs are not defective, use two meters. Have one measure the gate voltage and the other measure the drain voltage. Do the voltages remain the same as you posted here?
If the FETs are not defective, use two meters. Have one measure the gate voltage and the other measure the drain voltage. Do the voltages remain the same as you posted here?
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