Ive got a GT-40 that has speaker output levels about 1/2 the volume on both Left channels than on the Right channels.
Took a look at some notes and decided to remove all 4x 1UF caps, C38, C39, C40, C41. The problem is, the signal with the caps removed is still only about half on the leading pads of those left channels using my scope against function generator. And the caps are measuring OK off the PCB.
I have not removed the board from the sync as I don't want to damage the sync retainers if I don't have to.
Does anybody know if there is some kind of muting circuit under the board I may be missing? A schematic would be helpful with these Boston amps. I'm going to work on 3x Boston GT-42 amps next also.
Took a look at some notes and decided to remove all 4x 1UF caps, C38, C39, C40, C41. The problem is, the signal with the caps removed is still only about half on the leading pads of those left channels using my scope against function generator. And the caps are measuring OK off the PCB.
I have not removed the board from the sync as I don't want to damage the sync retainers if I don't have to.
Does anybody know if there is some kind of muting circuit under the board I may be missing? A schematic would be helpful with these Boston amps. I'm going to work on 3x Boston GT-42 amps next also.
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The clips are as easy to remove as on other amps. I've never had one break.
Does your signal source have a grounded shield (0 ohms between source shield and 12v power supply ground)?
Check both channel grounds.
Did you try swapping the inputs?
Do any of the pots or switches make a difference?
The attached is the only Boston diagram I have.
Does your signal source have a grounded shield (0 ohms between source shield and 12v power supply ground)?
Check both channel grounds.
Did you try swapping the inputs?
Do any of the pots or switches make a difference?
The attached is the only Boston diagram I have.