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Old 11th Mar 2006, 11:50 pm   #5
Jim - G4MEZ
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Join Date: Feb 2006
Location: Newport Pagnell, Buckinghamshire, UK.
Posts: 85
Default Re: Low hum on a Bush VHF64

Quote:
Originally Posted by Stewart
I had this exact same problem on one of my VHF64s - and as Setappeal says it was due to chassis members not making good contact with each other. I found this out by connecting a probe to the negative of the main electrolytic and moving around the various points that should be "grounded". An resistance check failed to reveal the problem - but this method did! If I remember correctly it was one of the side chassis panels that was not making good contact - even though it looked clean and secure.

Once attended to the set runs alomost silently! Good luck!

Stewart
Bingo!!! 'Twas exactly what it was. I have only so far tightened those I could easily get to by removing the back and the difference is quite marked. I'm sure whan I have the chassis out and do it properly it will then be 100% good. Some of the screws were so loose to be no more than hand tight. Thanks Stewart and setsappeal

Jim
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