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Old 31st May 2013, 07:11 PM   #41
ffejgo is offline ffejgo  United States
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Finally put the 2.2uf cap in today. I now have 298-304v across R30. So the lower cap took care of my high voltage issue.
But...
I have a 3 way input selector switch and it didn't matter which pole was selected they were all dead quiet. Now I have a hum when no inputs are connected. The hum wasn't there previously when nothing was connected (except the speakers). All I did was swap out the 22uf for the 2.2uf cap at C4. Would the lower cap value contribute to a hum in the system?

I can live with it since on the 2 inputs I am using 1st one is quiet, the 2nd one has a very slight hum with my ear within a couple of inches and the 3rd... I can hear it from the kitchen (greater than 25feet). Could it be the switch?

I don't know why I now have a hum?? Any help is appriciated.
Thanks ahead of time for your responses.
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Old 31st May 2013, 07:20 PM   #42
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Quote:
Originally Posted by ffejgo View Post
Now I have a hum when no inputs are connected. The hum wasn't there previously when nothing was connected (except the speakers).
Triple check your wiring.....

Does the hum go away if you short the inputs when nothing is connected?
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