They appear to be the secondary snubbers. Did you remove them to see if they read open or gave you some sort of resistance?
Are the caps shorted? They look like they overheated.
As a side note, these are not critical to basic operation of the amp. The amp should work without them.
Are the caps shorted? They look like they overheated.
As a side note, these are not critical to basic operation of the amp. The amp should work without them.
Pulled the resistors they are reading 8.3k and 8.5k. The caps are not shorted, adn check good (in board).
I did replace a blown apart 1n400n diode around the emitter resistor.
I did replace a blown apart 1n400n diode around the emitter resistor.
What's the value of the capacitor? I'm trying to find a similar amp.
Did you try to contact the manufacturer (do they still exist?)?
Did you try to contact the manufacturer (do they still exist?)?
Unless someone has more definitive information, I'd use something in the 220 ohm range. You may want to go to a higher wattage. Replace the series caps as well if they're much darker than other similar caps in the amp.
Ok Perry, thanks. I know this is not what the problem is since its pulling high amps with the output transistors in the circuit. When I pulled them out, the amp didn't pull high current.
I am not getting voltage across the emitter resistors. I have my ps set for 3amps and voltage drops to 7.3vdc.
Think it may be a good idea to pull the outputs and check the resistors that away?
Think it may be a good idea to pull the outputs and check the resistors that away?
The voltage would be in the mv range. If the output stage is the problem, the current almost certainly has to be flowing through the output transistors.
If it's not clamped down, check the heating of the outputs to see if they're heating up.
A current limiting resistor typically works better than the limiter in a power supply.
If it's not clamped down, check the heating of the outputs to see if they're heating up.
A current limiting resistor typically works better than the limiter in a power supply.
Problem must be in power supply, outputs are not heating up at all. I am getting 4.8 to 5 mv across the emitter resistors.
Some of the fets in the ps are heating up. I have been shutting off the power supply when the amps rise. Not giving it time to heat anything up.
Some of the fets in the ps are heating up. I have been shutting off the power supply when the amps rise. Not giving it time to heat anything up.
What work have you done to the power supply?
Sometimes letting it draw current for a few seconds lets components in the problem area heat up and can help with troubleshooting.
Have you clamped it to the heatsink and powered it up with no limiting to see if the current draw was simply inrush?
Sometimes letting it draw current for a few seconds lets components in the problem area heat up and can help with troubleshooting.
Have you clamped it to the heatsink and powered it up with no limiting to see if the current draw was simply inrush?
I have not done any work in the power supply section. The only thing I have done is replaced a blown diode in the output section. I believe this to be the over current circuit.
I have not clamped it back in the heatsink. I will try that before I go any further.
I have not clamped it back in the heatsink. I will try that before I go any further.
It is not an in rush issue. All transistors are clamped down. Amps go up and voltage drops. Have a power light and not a protection light. Fixing to pull her back out of the heatsink.
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