I just completed a rebuild of an SCA-35. The phono output is virtually nonexistent, you can just barely hear it at full volume, I mean barely at all. All other high level inputs are fine. The turntable is preamped and switchable on or off so even when the preamp is on (high/line level) output the audio is just barely there at all at full volume through any of the phono inputs but again it works through the line levels so I know the turntable s functioning properly. I'm at a loss. Every resistor and cap in the entire unit is new, both cap cans are new. The PEC modules are original and I did not test the phono before the rebuild. Seems unlikely they would both L/R be bad. Is there a simple way to remove the PEC's, leaving the other old inputs inoperable. One phono input for mm phono is fine. It's almost as if the phono section isn't getting amplified or is being retarded by something but I cannot trace it down.
2 posters
SCA-35 phono input issue
peterh- Posts : 1833
Join date : 2012-12-25
Location : gothenburg, sweden
- Post n°2
Re: SCA-35 phono input issue
An easier way is to inject 5mV 1khz into the phone input and follow the signal with a scope.DynaMan63 wrote:I just completed a rebuild of an SCA-35. The phono output is virtually nonexistent, you can just barely hear it at full volume, I mean barely at all. All other high level inputs are fine. The turntable is preamped and switchable on or off so even when the preamp is on (high/line level) output the audio is just barely there at all at full volume through any of the phono inputs but again it works through the line levels so I know the turntable s functioning properly. I'm at a loss. Every resistor and cap in the entire unit is new, both cap cans are new. The PEC modules are original and I did not test the phono before the rebuild. Seems unlikely they would both L/R be bad. Is there a simple way to remove the PEC's, leaving the other old inputs inoperable. One phono input for mm phono is fine. It's almost as if the phono section isn't getting amplified or is being retarded by something but I cannot trace it down.
Have you done anything with the signal switcher ?
DynaMan63- Posts : 2
Join date : 2019-07-28
- Post n°3
Re: SCA-35 phono input issue
All I have is a digital multimeter and of course I could output the signal from my PC, or use the turntable if that would work.
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