hammond m3 vibrato/chorus

[chillphil]

hello all
i have a slight problem with my organ. the vibrato and chorus function is not opperating properly.when the switch is in the off position the organ functions normaly, when the switch is engaged the volume drops to zero. the only thing i have done to try and remedy this problem has been to replace to tubes, but this had no effect. i have the full technical manual for the organ with scematics and all of that. if anyone has a sugestion for a posible solution to this problem i would greatly apreciate the tip.~thanks

[hh]

At the risk of stating the obvious, there must be a break in your vibrato circuit, anywhere from the switch itself to the scanner or somewhere in the vibrato drive & recovery amp. I'd spray the switch contacts with cleaner to begin with. Try holding your finger close to some of the capacitors in the circuit, but stay away from the tubes' high voltage of course. When I do that on my T-582 (which is solid state, but probably similar from a basic operation standpoint), it hums whether the switch is on or not, which indicates that the amp is working. If you can't get any hum, then you may have blown a component in the amp.

If I disconnect the input or output wire on my vibrato drive amp, I still get faint leakage sound when I press a key. Since you get zero, which is what I get when I pull the V+ to the vibrato amp, that indicates it's likely your amp is dead. Check its power first, and then start checking individual components, for excessive browness or opens when they should be resistors, etc.