sssboa
Super Member
Hi
I opened my CR-1000, measured some voltages, replaced 4 caps on preamplifier (Filter Amp) from 10uF63v to 10uF35v. Had to resolder a few cables on the filter amp as well. I turned the receiver on and I have humming on both channels, irrespective of volume setting, doesn't change with volume at all.
I measured voltage again and now I have 62V from power supply to the filter amp (through tone amp). Before it was 52V.
I never touched the power supply. How is it possible that changing caps on filter amp (preamplifier) and resoldering some wires that snapped off in the process caused different voltage from power supply?
When I decouple preamp the humming gets like 5 times less loud but still is there.
If you remember after doing similar maintenance on preamp of my other CR-1000 (also changing some caps on the small preamp boards) I lost completely one channel, still haven't solved it either. That's why I opened the other Yammy, to compare the voltages, that were the same btw ( also for the lost channel) until the humming issue started. So the not humming Yammy (but without one channel) still has 52v from power supply to filter amp, the humming one 62v.
Strange, before, I did full recap with pre-emptive change of many transistors in one go on CR-1000 and I never had a major problem like now doing small things
I opened my CR-1000, measured some voltages, replaced 4 caps on preamplifier (Filter Amp) from 10uF63v to 10uF35v. Had to resolder a few cables on the filter amp as well. I turned the receiver on and I have humming on both channels, irrespective of volume setting, doesn't change with volume at all.
I measured voltage again and now I have 62V from power supply to the filter amp (through tone amp). Before it was 52V.
I never touched the power supply. How is it possible that changing caps on filter amp (preamplifier) and resoldering some wires that snapped off in the process caused different voltage from power supply?
When I decouple preamp the humming gets like 5 times less loud but still is there.
If you remember after doing similar maintenance on preamp of my other CR-1000 (also changing some caps on the small preamp boards) I lost completely one channel, still haven't solved it either. That's why I opened the other Yammy, to compare the voltages, that were the same btw ( also for the lost channel) until the humming issue started. So the not humming Yammy (but without one channel) still has 52v from power supply to filter amp, the humming one 62v.
Strange, before, I did full recap with pre-emptive change of many transistors in one go on CR-1000 and I never had a major problem like now doing small things
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