Hi all,
I bought a Revox B750 mk2 amplifier a while ago, and it had some issues with dropping channels and it was quite scratchy on the knobs. So I bought an upgrade kit from this German website (http://www.revox-online.de). What a struggle! As I don't speak German and the gentleman on the other side don't speak English, but that's another story. It is basically a full cap replacement kit for all the boards in the amplifier.
I took my time and replaced all the caps, but on putting everything back together, the right channel now has a constant buzz coming through. The left channel is fine. I have tested the preamp out into another power amp, and have swapped the left/right power amp boards, so the problem definitely lies on the right channel's power amp board.
The board still makes music, it just has this constant buzz coming through as well.
Something I did notice though is that the two big filter caps on the right channel board has small dents in them. Can this cause the issue? or is it more likely a bad soldering joint or a dodgy ground connections? I don't really have the tools to test things properly, I only have a digital multi meter.
So I guess my main question is... does anybody have any advice on how to start troubleshooting this?
And does anybody know of anyone in cape town that I can take the amplifier to that can help me troubleshoot and trace the problem?
Below is pictures (both of the net) of the amp and the power amplifier boards.
I bought a Revox B750 mk2 amplifier a while ago, and it had some issues with dropping channels and it was quite scratchy on the knobs. So I bought an upgrade kit from this German website (http://www.revox-online.de). What a struggle! As I don't speak German and the gentleman on the other side don't speak English, but that's another story. It is basically a full cap replacement kit for all the boards in the amplifier.
I took my time and replaced all the caps, but on putting everything back together, the right channel now has a constant buzz coming through. The left channel is fine. I have tested the preamp out into another power amp, and have swapped the left/right power amp boards, so the problem definitely lies on the right channel's power amp board.
The board still makes music, it just has this constant buzz coming through as well.
Something I did notice though is that the two big filter caps on the right channel board has small dents in them. Can this cause the issue? or is it more likely a bad soldering joint or a dodgy ground connections? I don't really have the tools to test things properly, I only have a digital multi meter.
So I guess my main question is... does anybody have any advice on how to start troubleshooting this?
And does anybody know of anyone in cape town that I can take the amplifier to that can help me troubleshoot and trace the problem?
Below is pictures (both of the net) of the amp and the power amplifier boards.
