Hey guys I have a power 1051s on the bench. One channel has different voltages per fets. N channel side has 78V from pins left to right while P channel side has 50V and 48v from pins left to right. All outputs checked out fine none had short. All emitter resistors are in tolerance. Not sure what’s going on with this one. This is the left channel. Any tips appreciated thanks guys!
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Should I put them back in? The issue was it was pulling excessive current with them in so I pulled them. Or should I put in the p channel?
Did you set the bias pots to the full CCW position?
What do you consider to be excessive current?
Was the current draw immediate or only after a few seconds of delay?
What do you consider to be excessive current?
Was the current draw immediate or only after a few seconds of delay?
Yes I did before I removed the outputs. I was thinking maybe someone adjusted bias to high. On my power supply it was dragging the voltage down to 8 volts! Yes the current pull was immediate. As I mentioned all 10 outlets had no short. Really strange
Does the bias increase on the other channel when you rotate the bias pot clockwise?
The problem causing the high current draw could be a driver component.
The voltage drop on the power supply doesn't say much without knowing anything about the supply.
The problem causing the high current draw could be a driver component.
The voltage drop on the power supply doesn't say much without knowing anything about the supply.
Both power supplies on this amp are functional. Yes bias does increase rotated clockwise on the working channel. I put back in 9640 attempted to power up amp pulls current automatically with only half the outputs in. They are also heating up. Any ideas? I’ve checked A06 and A56 even replaced them same results.
Pins on 640 with no fets in have really high voltage present from gate - drain pins. 78v on source 79v on gate while 640 is much lower. Lost on this amp..
You can NOT use voltage on the output locations to troubleshoot when the feedback loop is open (no outputs installed).
I gotcha. It just seemed odd one side was very high. How can I go about troubleshooting this channel? There’s 13.98v at the terminals with no remote connected.
Contact Rockford and get the diagram for this amp. You'll need to PC# off of the board to get the correct diagram.
What's the DC voltage on all 3 terminals of the two voltage regulators on that half of the amp?
What's the DC voltage on all 3 terminals of the two voltage regulators on that half of the amp?
I found the problem. It was a defective transformer. Everything else was good. That’s why I was confused because none of the output fets were shorted. I had to unwind it to find the short. Amp works again