Hi everyone,
On my first amplifier repair. It was previously repaired by someone else, and when I opened it up I found that the output FETs were shorted on the negative rail. I removed the rectifiers and the power supply seems to be doing its job correctly. Before ordering and installing output FETs, I checked the gate signal. The side that had the shorted FETs has what looks like an ac wave in it, the other side seems good. I checked my 5v regulator and noticed it has a really dirty voltage coming in and out. I am not sure of what my next step would be. Am I able to remove the voltage regulator and see if that straightens out my issue, to help me see if its before or after? Would love some advice! I'm going to be at guard drills all weekend, but would like to be ready when I come home so I can figure it out!
Thanks in advance
Pic 1 is the dirty gate signal
2 is the dirty voltage regulator
3 is the 12v output from the transformer
4 is the other leg of above transformer
5 is the diagram from transformer to voltage regulator.
I found the diagram for a Massive SL1500 to be identical for my amp, same values and identification numbers, so that's the diagram I'm going off.
On my first amplifier repair. It was previously repaired by someone else, and when I opened it up I found that the output FETs were shorted on the negative rail. I removed the rectifiers and the power supply seems to be doing its job correctly. Before ordering and installing output FETs, I checked the gate signal. The side that had the shorted FETs has what looks like an ac wave in it, the other side seems good. I checked my 5v regulator and noticed it has a really dirty voltage coming in and out. I am not sure of what my next step would be. Am I able to remove the voltage regulator and see if that straightens out my issue, to help me see if its before or after? Would love some advice! I'm going to be at guard drills all weekend, but would like to be ready when I come home so I can figure it out!
Thanks in advance
Pic 1 is the dirty gate signal
2 is the dirty voltage regulator
3 is the 12v output from the transformer
4 is the other leg of above transformer
5 is the diagram from transformer to voltage regulator.
I found the diagram for a Massive SL1500 to be identical for my amp, same values and identification numbers, so that's the diagram I'm going off.
Attachments
Last edited: