Vintage Synth Repair

I recently bought a 31h and when I attached it to my model A discovered 
there was a rather loud hum comming from the bass rotor. After it has 
been on for a few minutes, the hum get much quieter, but dosen't go 
away. Anyone have an idea that I can try. Thanks.    Mark.

Mark;
Have you had the Hammond A amplified prior to this time?
 
It is possible the 31H needs to have its filter and coupling caps
replaced.
 
It is also possible there is a poor ground connection between the organ
and Leslie.
 
Mike
 
 
<snip>
 
I recently bought a 31h and when I attached it to my model A discovered 
there was a rather loud hum comming from the bass rotor. After it has 
been on for a few minutes, the hum get much quieter, but dosen't go 
away. Anyone have an idea that I can try. Thanks.    Mark.

These are all good sources of information
 
HAMTECH@...
 
hammond@...
 
hammond_zone@yahoogroups.com
 
http://theatreorgans.com/hammond/faq/
 
http://www.dairiki.org/HammondWiki/
 
www. <http://www.captain-foldback.com/> captain-foldback.com
 
www.speakeasyvintagemusic.com <http://www.speakeasyvintagemusic.com/> 
 
www. <http://www.tonewheelgeneral.com/> tonewheelgeneral.com
 
http://www.bentonelectronics.com/
 
 
Mike
 
<snip>
 
Michael, thanks for your answer. Yes, I had the A attached to a tone
cabnet and ther was no hum. Michael, I'm a middle aged rookie, when it
comes to the technical stuff. Will you direct me to a site wher I can
find information, regarding filters and caps? Thanks again,,,, Mark