Percussion won’t decay on only one key

[SpaceOrgan]

I have an M3 I have been working on. According to the Captain Foldback site, it is from 1958. I’ve got it all almost perfect, except for one tiny problem.

I recently pulled the upper manual to repair some key contacts on the top C key, it all went back together pretty smoothly and I didn’t really notice any problems until I was looking for missing tones and found one on the lowest G, top drawbar. This tone works on all other keys (poor man’s foldback). I also noticed the percussion will not decay on that same note.

I shifted the bus bars and checked my solder connections from the tone generator and all that checked out fine.

Any ideas? I’m thinking a broke a connection on a resistance wire while I had the manual out, but I want to get some ideas before I go through the ordeal of pulling the manual again.

Thanks all!

[Bobmann]

I have an M3 I have been working on. According to the Captain Foldback site, it is from 1958. I’ve got it all almost perfect, except for one tiny problem.

I recently pulled the upper manual to repair some key contacts on the top C key, it all went back together pretty smoothly and I didn’t really notice any problems until I was looking for missing tones and found one on the lowest G, top drawbar. This tone works on all other keys (poor man’s foldback). I also noticed the percussion will not decay on that same note.

I shifted the bus bars and checked my solder connections from the tone generator and all that checked out fine.

Any ideas? I’m thinking a broke a connection on a resistance wire while I had the manual out, but I want to get some ideas before I go through the ordeal of pulling the manual again.

Thanks all!

Only one missing tone on only one key/drawbar combination means there is a contact problem. If you are missing the same tone on multiple key/DB combinations, the problem lies with the TG or the wiring between the TG and keyboard.

If bussbar shift did not clear it up, it looks like the resistance wire may be a logical suspect...or there is an off chance that the one contact is not touching for some reason.
On the very outside chance that the contact actuator is not pushing down all 9 of the contacts, take that particular key off and push the actuator down with your finger.

Just make sure that there are absolutely no other missing tones on any other key/drawbar combinations before you proceed to make sure you are looking in the right place.

Bob

[SpaceOrgan]

Is this THE Bobmann from YouTube? I also saw a news piece about you? Thanks for the reply. I looked at the key contact under magnification and it does have a pretty good dent in the palladium wire. I have contacted someone for a replacement. It is the upper manual, lowest G, white drawbar. The contact is one with a green wire. I have a parts organ now, but it is from 65 and I believe it has the black foam, which means it has the lacquer coated resistance wires, right? I just got it today for free and haven’t had a chance to open it yet.

It looks like it just wouldn’t trigger the percussion, though, rather than triggering and not decaying, but I’m pretty new to working on them.

Thanks again.