The other half of the amp is likely OK.
Compare the readings (ohms and diode check) for each of the driver components (diodes and driver transistors) in one half to the ones in the other half of the amp. Probe placement is critical so make sure you place the probes on the corresponding components the same way. Place them one way then reverse them. Do you see anything that doesn't match?
Discharge the caps before you begin.
Compare the readings (ohms and diode check) for each of the driver components (diodes and driver transistors) in one half to the ones in the other half of the amp. Probe placement is critical so make sure you place the probes on the corresponding components the same way. Place them one way then reverse them. Do you see anything that doesn't match?
Discharge the caps before you begin.
all of the parts seem to read identical in the circiut so i tried a to drive a 2 ohm load with it and shortly after it popped a couple outputs (ddaammnn!!!). so i found the shorted parts and replaced them. i'm guessing now all the outputs will only be good for testing. Q417 was shorted between all 3 legs and Q429 was shorted between legs 1 & 2. i also found Q409 shorted between legs 1 & 2. so i replaced all 3 bad parts i found and restarted. and same thing i put the 2 ohm load on it and it popped again. i haven't checked to see what's bad this time yet.
Check D407, D410, D411 and D412. You should remove them for the circuit. Confirm that the forward voltage is no more than 0.75v for the Zener (D412). The others should have lower forward voltage. They may have reverse leakage also. Post the resistance (reverse polarity) if one seems to be different from the others.
well i almost forgot about this amp it's been so long. i stopped a while back because i ran into some problems and got sidetracked. when i put it on a 4 ohm load it looks okay (60 hz sine wave), but if i drop it to a 1 ohm the output looks okay until i get to a certain volume level and then the tip of the bottom half gets fuzzy. this blew a set of outputs very quickly. so now i got the new IRFP264n's installed again and had to replace some driver components (R416, Q409, Q406, Q407). i tried it out a few minutes ago with the same result, besides blowing my new outputs (my reaction is now much quicker). i have pulled and checked every driver component for not only the outputs that i replaced but the other side also. as for as the other side everything was good but R411 (it was at 12.6 ohm, should be 10 ohm) so i replaced it.
i'm just curious. i am only using a 13.8v 40 amp power supply, could this be my problem.
i'm just curious. i am only using a 13.8v 40 amp power supply, could this be my problem.
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