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fisher 800c intermitant hum
fisher 800c intermitant hum
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Old 27th May 2007, 11:59 PM   #1
slhoward is offline slhoward  United States
diyAudio Member
Join Date: Mar 2007
Angry fisher 800c intermitant hum

No sooner do I get one thing fixed, than another thing starts to go bad. Lately my fisher 800c has developed an intermitant hum in the right channel. I have replaced all caps, I mean all electrolytics. I was told that plate resistors that are going bad can cause this?

Where would I look to fix this issue? The driver phase inverter tubes or the 7591 outputs.

Am I right concerning the plate resistors.? I swapped the output tubes around as well as the drivers and no change, so I don't think its the tubes. I checked the grounds and they appear ok.

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Old 28th May 2007, 05:16 PM   #2
slhoward is offline slhoward  United States
diyAudio Member
Join Date: Mar 2007
Smile problem fixed

Found loose coupling cap at output stage. Sorry for hastle and unnecessary thread.

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