[sdiy] keyboard: good designs?

[MED]

On Thursday 20 November 2003 16:24, Ray Wilson wrote:
> Another source: pawn shops.
>
> Also I can't help but wonder why people in Santa Barbara can't give organs
> away? Is there some law against it? Does Arnold know about this?

I guess no one wants the ancient organs that warm up rooms and have horrible 
leakage/drift problems caused by thirty-year-old (sometimes paper) 
capacitors... for some reason.

> I am always on the hunt for keyboards too. I hate to part with $300.00 to
> $400.00 to get something I'm going to tear up. You can also switch-ify (I
> want credit for that word) an old piano keyboard and there are tons of old
> pianos around that people just want hauled away.

Okay, now this's going to be a pretty darn newbish question but i've been 
hunting around the net and going through schematics and whatnot and i can't 
find an answer. How do you connect keyboards to generate 1V/octave? I'd 
especially prefer to not use a microcontroller/digital scanner, because it 
seems truly overkill.
I've got three keyboards (pulled from an organ -- two manuals, one 
pedalboard). 
The manuals both have about 47 keys.
One has four metal rods running all throughout the keyboard, which are 
contacted by pins when the keys are pressed. I'm assuming these are the 
"buses" to which everyone refers. Correct me if I'm wrong, for I'm not sure 
if I have the lingo down properly :)
	The other keyboard simply switches between one metal rod when the key is up 
and another metal rod when the key is down, but has a wire coming from every 
key. Would this be two bus, or one bus?
The pedalboard (24 note) is more complex. I think was already wired for 
lowest-note-priority monophonic sound, because that is how it operated on the 
organ I pulled it from.
There are three pins per key: a common pin, a normally-closed pin, and a 
normally-open pin. The moving (connected to the key) pin rests on the top 
(NC) pin while unpressed, and it moves to touch the bottom (NO) pin when 
played.
It was soldered so that, from the top of the keyboard on down, the 
normally-closed connection of one is soldered to the pin connection of the 
next, and so on down the line. The lowest note's normally-closed pin is 
unconnected.

What is the best approach to make 1V/oct keyboards out of each of these 
keyboards? I mean both in terms of physical/wiring connection and electronics 
involved. I've been struggling with this for a while and want hte help of 
someones more experienced.
Thanks in advance,
-MED