[sdiy] Anyone have schematics for a Kimball Organ rhythm machine?

[Oren Leavitt]

On 4/26/2012 4:45 PM, aankrom wrote:
> Thanks to some helpful info from one of you, I've learned that my unit
> is very similar to a Roland TR-77. The size of the units are even
> similar, but the circuits are, as expected, not identical. The TR-77 has
> more features - some that I'd like to add. There's an octal socket on
> the back of mine that looks like it could be discrete outputs for each
> sound or maybe triggers. I'm curious as to what could have been
> connected there.
>
> I wish my rhythm unit had each sound circuit marked on the PCB like on
> the TR-77. I can surmise which is which based on the size of the
> inductor bobbins, but that's about it. Some probing is in order...
>
> It will be cool when I have it all boxed with the 25W amp and the reverb
> unit.
>
> Anyone who's hacked a TR-77 or a unit like it, I'd welcome input or
> pointers to sources on the web. I like the tip on pushing buttons for
> two patterns at once. I don't know yet if that will work on mine, but
> I'm curious to see what comes out. The diodes on the pattern generator
> are these weird black plastic blobs...
>
> AA

Sounds similar to the Ace Tone (Before they became Roland) Rhythm Ace of 
the late 1960s.

- Oren