Looking for a Hammond Organ repair manual...

Hey guys,
I don't know if this is a "bad" thing to be asking for here or not because of the age of the unit, etc. I've got a R-128. This is the R-100 series tone-wheel organs that they made in the early 70's. My understanding is that it is the same guts as the B-3 (different cabinet) except all transistor amps and built in cabinets. Anyway, two of the tone bars are not working and I've been trying to trace the issue with no luck. I saw there are some companies selling the old manuals for $65+, but I don't know if that would even help me...Anyone have any leads on these manuals, or experience fixing tonebars?

Thanks.
Joel

Do you mean tonewheels or drawbars? Two different things.

I mean drawbars. I've also seen them called "tonebars" in some of the manuals. Specifically, the Root drawbar and the first overtone drwabar for the upper manual don't work. They used to. I just got this a couple of months ago, but in moving the 400 lb beast, something came disconnected I guess...
Joel

The easiest thing to do is make sure the wires for each drawbar are connected. One wire per drawbar, color coded. They can snap off during transport. Just open up the back... there should be one wire coming off the back of each drawbar.

http://www.captain-foldback.com/Hammond_sub/hammond_schematics.htm

Thanks for the reply guys, I've been out of town and just now can reply. Unfortuanetly, I already saw that schematic link and it's pretty much unreadable. The wires are connected to the drawbars as best I can tell. There's A LOT of freaking wires in the back of those. Still looking for a full manual...

Joel

hi Joel ,

If you could do a few searching out measurements and compile a few questions, I could pass on your info to my friend .
He repairs these older organs all the time , usually without the luxury of schematics. He may be able to point you to things to check.(He is not connected to the net. )

cheers,
Lance

Thanks hitchiker. As best I can tell, the wires are going from the drawbar to the switches for "built in stone settings" to the percussinn relays then on and on. If I play a note I don't hear the root-note, or the first harmonic when in the "drawbar" setting, but if I switch the setting to some type of preset (like brass for example) then those root note and overtone do come thru, maybe that helps explain?

Joel

Hi Joel,

I just got back from vacation and checked my service manual - it doesn't cover your model. If you're getting all the partials when you use a preset but not when you use drawbars it sounds like you might have dirty drawbar contacts. Forgive me if you know all this already. There are (I think) nine contacts for each drawbar. If you push a key down very slowly with all drawbars out you can hear each additional partial start as you make contact with each. Have you cleaned the drawbar contacts? If you take off the back of the organ with the drawbars all in you should be able to see the ends where the wire is soldered onto each end. I'm going from memory of my RT-3 here - so look at yours and make sure it works the same way. When you can identify each drawbar by pulling them in and out you can carefully put a little DeOxit on a Q-tip and clean them. I don't remember if it makes contact on the top or the bottom. See if that does it. You should hear all the partials one by one when you push a key down slowly. Let me know if this gets you anywhere. When I find a minute I'll re-read the manual and see if there's more.

Good luck,

hi Joel,

besides the previous advice....my friend says...

first thing to try is to reach in and shift sideways the drawbar whisker contact to maybe get a good connection and hear the frequency.
sometimes this is difficult because you have to be able to identify the
bar from the back side and sometimes you have to get in with long needle nose pliers.

If that doesn't work then you really need the two pages from the manual
that give you the note frequecy table and the tone wheel generator location for that frequency.

And I think there are wires that can be broken there but it's very difficult without the manual pages to guide you to the phisical location.

Unfortunately he has no info on any of the R series but says that he sometimes gets those two pages from another repair shop when he's
doing a repair.

I hope this helps ,
Lance