[sdiy] Info request (longshot) - Technics keyboard mech/encoder

[Steve Lenham]

Hi,

I've acquired a lovely graded hammer-action keyboard mechanism from a 
Technics PR-series digital piano/ ensemble.

I can think of lots of things to do with it, but before I rush in and start 
making contact strips and encoders from scratch I just wondered if anyone 
had any information or schematics for Technics' own encoder circuitry? In 
particular:

1. There is an encoder board mounted on the mechanism with a 64-pin Technics 
M7U042-016 IC (presumably some sort of ASIC/mask-programmed device) and a 
serial EEPROM. It connects to the rest of the instrument via a 16-way cable. 
Anybody know anything about this circuit or what connections are required to 
it?

2. The key contacts themselves are not the usual 
spring-wire-plus-two-busbars that I was expecting to see; instead, there is 
a row of individual rubber buttons sitting on the PCB. Normally I would 
associate that sort of thing with cheapo keyboard mechanisms, but this is 
from a multi-thousand pound/dollar/euro instrument which I know for a fact 
plays very well and has first-class velocity sensitivity. It's not obvious 
how that sensing is done - anybody know? (Obviously I could learn more by 
taking it to pieces, and probably will in the end, but perhaps someone knows 
already).

Any information, however minor, would be much appreciated.

Cheers,

Steve L.