Thread: Ts4d Motorola
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Old 03-24-2018, 02:12 PM
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timmy timmy is offline
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Quote:
Originally Posted by robert1 View Post
This is where the method of *Process Of Elimination* comes in handy. What i would suggest is to disconnect what is connected to pin 2 on V7 (6SQ7) & then power up the set & see if you still have hum. there should be silence. if the hum stops, You can eliminate the audio amp & output stage as being the problem. the problem then, would be somewhere upstream in the I.F. or in the audio detector stages. If the hum is still there, there is a problem with the source voltage from the B++ rail that supplies the audio amp stage.

Are you sure that the hum is a 60 cycle ripple, & not a buzz caused by sync pulses?
Well it sure does sound like 60 hz it's sure loud enough and don't sound like a buzz but rather 60 hz .
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