Hum on Hammond L-122

[tonewheel1966]

Hi</P>


I recently aquired a Hammond L122. It is immaculate (church owned) but was sold to me as a non runner as the TG would not kickin. I don't know if it was the journey home from London but when we got her home she fired up. What happens with the hum is it appears about 15-20 secs after turning on(as the valves warm up). It is coming through the speakers (disappears when disconnected) and is very deep. It seems to "mimic" the sound of the TG running. I have removed the valves and cleaned their sockets with switchlube but this has made no difference.</P>


Is this a common fault?</P>


It hadn't been played for over a year and before that it hadn't been played for years.</P>


Cheers</P>


Dave</P>
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[bluetantra]

Re: Hum on Hammond L-122



Dave-</P>


My first guess would be failing electrolytic capacitors. You should be able to find the original FP type of multi-section capacitor (the aluminum can on the main amp chassis) from Antique Electronic Supply (www.tubesandmore.com). If you're not concerned with originality, individual axial or radial caps of equivalent value will work fine.</P>

[tonewheel1966]

Re: Hum on Hammond L-122



Before I had the organ, the previous owner said that it had refused to start on several occasions I mean no light or anything. Could this be linked?</P>


It would be nice to kill 2 birds with1 stone!</P>


Do these caps just pull out like the valves and how do I de-energise them?</P>


Many thanks</P>


Dave</P>
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