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Troubleshooting from a schematic
To: CRTech <crtech@crtech.org>
Subject: Troubleshooting from a schematic
From: Dan Harder <dan@am91.org>
Date: Tue, 2 Jan 2018 07:12:44 -0700
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Hey all,

My son inherited an old Crate brand instrument amp from his uncle last summer. It worked well for about 3 months, and now is a white noise generator and only the smallest amount of audio from any of the 3 inputs leaks thru.

I have schematics, but the PC board is not marked at all, and I’ve spent several hours trying to determine the cause. I have access to a fluke scope-meter, 

The noise is constant and does not vary with any knob adjustment.

Would anyone here mind a look at the drawings and venture a guess as to what component(s) might be guilty?

Private message me if you’re interested.

Dan Harder

Follow-Ups: Re: Troubleshooting from a schematic
(Sherrod Munday <smunday@ieee.org>, 2 Jan 2018 18:39:27 -0000)
RE: Troubleshooting from a schematic
("Wiely Boswell" <wiely@faithradio.org>, 4 Jan 2018 15:55:37 -0000)
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