Are all missing?
According to my notes, all are IRF540s.
Do NOT power up the amp without having these tightly clamped to the heatsink. They can overheat and fail within seconds and do extensive damage.
According to my notes, all are IRF540s.
Do NOT power up the amp without having these tightly clamped to the heatsink. They can overheat and fail within seconds and do extensive damage.
It's normal for linear regulators to heat up, especially when they're dropping about 60v.
Do you read approximately 18v between pins 5 and 8 of the two 3120 optocouplers?
Do you read approximately 15v on pin 8 of the op-amp near the RCA jacks?
Do you read approximately -15v on pin 4 of the op-amp near the RCA jacks?
Do you read approximately 18v between pins 5 and 8 of the two 3120 optocouplers?
Do you read approximately 15v on pin 8 of the op-amp near the RCA jacks?
Do you read approximately -15v on pin 4 of the op-amp near the RCA jacks?
If you look at the solder connections before you desolder the FETs, you can almost always tell what's original and what's been soldered by hand.
For amps that use silpad insulators, you can also use the impressions in the pads to determine if more than one FET has been clamped in each location. It's rare to get all replacement FETs to lay perfectly where the originals were.
I don't know what the originals were but those would be OK. .
For amps that use silpad insulators, you can also use the impressions in the pads to determine if more than one FET has been clamped in each location. It's rare to get all replacement FETs to lay perfectly where the originals were.
I don't know what the originals were but those would be OK. .
Yes, all the power supply FET's are 75339P and numbered as follow on one side of the heatsink: FET103 FET107 FET105 FET111 FET109 on the other side numbered as FET104 FET108 FET106 FET110 FET112
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