It should only be about 1/2v less than at the IC. Are you sure that the drivers have supply voltage (12v on the collectors of the NPN drivers)?
Is the problem the same for both outputs on the header?
Is the problem the same for both outputs on the header?
Thaks sean thats perfect. I think it is ok now. right around 5v on the gate drives. I ordered 12 irfp064n from arrow but they sent me 5-7 different date codes, wth. So i either go with them or at least i probably have 6 other matching ones so i could at leat match each bank.
Sean has repaired a lot more of these than I have so he may have a different opinion. I'd use the original values (half 60.4, the other half 47.5) all 47 ohms will likely be perfectly OK as well.
Perry despite my best efforts the power supply mosfets still overheat. If i attempt to power up the amplifier in the q6-q5-q4 location. The amplifir instantly drew 10amps of current and the mosfet in location q5 was hot within seconds? Shorted transformers?
Post the waveform of the hottest FET, taken directly from the leg of the FET (not from any other point in the drive circuit). Do not connect B+ so there will be no excessive current draw.
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