Wondering if there is a good cross to theese power supply fets The one that are in the amp now are: P75N758
Neither could I . I Ill try the part you listed as a replacement. Do you want me to take a high res pic and post it before i order parts?
If you can take a good quality photo, post it.
Have you tried wiping a bit of heatsink compound on and then off of the transistors to see if it makes it easier to read?
Have you looked at other transistors to see if others were easier to read?
Have you tried wiping a bit of heatsink compound on and then off of the transistors to see if it makes it easier to read?
Have you looked at other transistors to see if others were easier to read?
Replaced the power supply fets and gate resistors I also checked the drivers all seem to test fine.
But heres my problem 6 out of 12 of the fets the gate signal looks like PIC 1
ANd the other 2 look like the 2nd pic. AMp draws excessive current.
Any ideas on where to start looking?
But heres my problem 6 out of 12 of the fets the gate signal looks like PIC 1
ANd the other 2 look like the 2nd pic. AMp draws excessive current.
Any ideas on where to start looking?
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It's strange that they're different but I don't see anything that would cause it to draw excessive current. Did you try removing the rectifiers to see if the excessive current draw was eliminated?
Removed the rectifiers ANd the power supply fets get red hot within 2 secs. Also amp trys pulling 15 amps of current
It's difficult to tell but when viewing the left gate waveform at full resolution, it appears that the PNP driver transistor may be defective.
Black probe on ground and red probe on leg 1 of the first 1275:3.75 volts
The other is 4.96 volts.
if i set the meter to ohms from 1 of the 1275's to ground is .463K ohms and the other is.465K ohms
The other is 4.96 volts.
if i set the meter to ohms from 1 of the 1275's to ground is .463K ohms and the other is.465K ohms
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