Ca 810 no audio signal from pre out.

Good morning !!
Been working on this 810 for awhile.Got her running.
Today I turned her on..relay clicks no audio.Hmmmm.
No meter deflection.I bypassed the pre/main connection and went directly
into main in.Plugged in headphoines and I get audio.Put everything back
the way it was and I get humming /buzzing sound through headphones.
Sounds as if something isnt grounded.Will double check everything again.

Audi2014 said:

Good morning !!
Been working on this 810 for awhile.Got her running.
Today I turned her on..relay clicks no audio.Hmmmm.
No meter deflection.I bypassed the pre/main connection and went directly
into main in.Plugged in headphoines and I get audio.Put everything back
the way it was and I get humming /buzzing sound through headphones.
Sounds as if something isnt grounded.Will double check everything again.

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I´d first verify that the pre-amps power source ( regulated DC supply) is putting out a good clean supply of approx. +/- 25 vdc to pins 9 and 10 of the power supply. You may have a one or more bad electrolytic caps in the regulated supply.Or even a bad solder connection in the same supply can be very noisy.(Check the pass transistors, in the reg. supplies solder connections:thmbsp They are the TO-220 transistors TR805 and TR806 .They should have small heatsinks fastened to them.