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yamaha c70 preamp phono dead kink of

thanks for the tip on checking for phono at the rec out, right now the phono section is well so now it seems the problem is the headphone amp, its there i'm getting the one channel that is
out.
so its on to the next lesson.
 
If your getting a good pre-amp out. Then check your +/- 17vdc to opamp IC508 pins 4 and 8 and your +/- 30vdc to the collectors of TR529 thru 532..
 
Head phone jack contacts may be dirty. Or even bad soldered connections.
 
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i checked ic 504 pins 4 and 8 and got 17vdc, tr529s collector pin shows 29 volts dc and tr532
collector pin gives -30 volts dc but tr537 and tr538 get very hot after a few seconds of use.
headphone out works for now i'm beginning to think the hp jack is on the way out. i will reflow
the hp wires in a few minutes and see if that fixs that.
 
avionic
well its time to start work on the c70 again i now have a audio signal generator and am
looking at the solid state o scopes on amazon it looks like i will not need anything above
100mhz.
do you have any experience with these?
 
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