Removing a drum machine from a Kimball 700 Organ to use as a standalone drum unit

[trumq]

You should be able to get the proper voltage by turning on the organ, and probing with a voltmeter the spot from which you disconnected the drum machine .

[Torea]

You might also try over on the organforum(.com). Lot's of people who know how to do what you want to do.

[SuburbanLoser]

Thanks! Unfortunately, pulled this out of an organ at a thrift store and ditched the organ so there's no way of testing it from the original source

[SuburbanLoser]

What is the technical term for the piece that connects to the white plastic part of the power supply? No definite answers yet but read somewhere that similar units take -25v power. Is that negative 25 volts??? Please help!

[brianroth]

That connector is a Molex plug. I have no clue what voltage the electronics requires.

Bri

[acreil]

There's no power transformer, so it's certainly not 120VAC.

[SuburbanLoser]

Hey, found a schematic for this. Not really good with reading these things - any help here on what you think the voltage for the plug is?

[mjrippe]

Looks like it takes 24v AC from the organ and converts it to -16v DC.

[SuburbanLoser]

So if I were to get a plug to connect I'd need a 24 AC Plug? Also, how do I connect to that molex plug?

[mjrippe]

Yes, you can look for a 24v AC adapter - a wall wart is fine, just make sure it is AC not DC. You can look for a matching molex connector or just cut it off and find a jack that matches your adapter.

[vince @ speck]

That's a rhythm machine....not a drum machine. Most of those older rhythm add-ons had basic clickin' & cluckin' & shaker sounds.

[Ghosted]

Why don't you just sample the sounds out of it and sequence your own patterns?

[aankrom]

I have one of these that I am making into a nice rhythm machine, using the amp and reverb from the organ.

The power supply is in the amp. Looks like the rhythm unit takes +18V from the organ power supply, though I would have guessed -18V. It's possible that it a positive ground, but this doesn't make sense because the organ has a -18V supply. There must have been a reason they wired it that way. I will go over the service manual again to check.

I'm glad I stumbled onto this post because the organ service manual does not include the rhythm unit (which is basically a modified Rhythm Ace FR-2L).

I can supply a link for the service manual for the Rhythm Ace FR-2L if anyone is interested.

Anthony

[aankrom]

Well I'm glad I doublechecked what goes to what on the Molex connectors.
The wire going up to the rhythm unit was red just like the +18V, so I assumed it was +18V. But the service manual for the organ said -32V was on that Molex pin (and that the wire was supposed to be pink).
The schematic that was posted shows 24VAC going into a single diode to make a negative voltage, but if you'll notice the posted images of the actual rhythm unit under discussion, the power lead (in the images in which they can be seen) goes right to that big green 100 Ohm resistor. There's no diode there (not on mine either).
You need -32VDC & a 24VAC transformer and a rectifier will give you that.

Anthony