[sdiy] Polyphonic keyboard scanner

[David G. Dixon]

Terry, that's a very tempting offer!  I'm in Vancouver BC, so I don't get to
LA much, although my parents live in N. California, and I'm having to visit
them more and more often (only surviving child, father with Alzheimer's,
mother barely coping...).  However, I'm sure many of us in synth-diy land
would love to see whatever you've got hidden under your bench!

> >> I will have the boxes brought out so I can look for them. I know I
> don't
> >> have them in electronic readable form. Just hard copy.
> >
> > Terry, I found the schematics (in the form of the service manual) for
> OB-Xa
> > here:
> >
> > http://www.lazyblueoctopus.com/html/oberheim.html
> >
> > One glance at these was enough to convince me that a microcontroller is
> the
> > way to go!  Does the circuit really need to be that complicated to do
> what
> > it needs to do?
> >
> Hi David,
> 
> The Z-80 was used for Keyboard scan, Front Panel control, Auto-Tune etc.
> 
> The E-Mu 4060 keyboard was about the simplist incarnation from that time
> point.
> 
> The 4060 was a 16 voice Gate and CV based system. Later on we added a disk
> drive and extended memory card to the the system.
> 
> Simple programs were loaded via Cassette using a Kansas City Style loader
> from a cassette deck.
> 
> The keyboard could be split and it was a true polyphonic sequencer
> controller.
> 
> I still have mine in the flight case in the Garage.
> 
> We never published the schematics for this design but I have the complete
> archive here in my Lab. The software listing is on a printout in a box
> under
> my work bench I think.
> 
> So much history is hidden with the dust and spiders in my garage I fear.
> 
> Where are you based at? I am in the Los Angeles area if you wish to
> explore
> some of this history.
> 
> Regards,
> 
> Terry