[sdiy] Crumar Composer: Breath controller

[Bob Weigel]

Well the resonance turned out to be just a trace I forgot to fix when I 
retro'd in the pots. doh.  I adjusted it up to have a good squeel and 
got the knobs all set up looking almost stock after a bit of pain.  The 
switches I got from all didn't mount very well.  Had to bend the shafts 
a little with heat even.  But it's done.  Now I guess I'll have to make 
something to extend the key spring contact alligners that are single 
spring on the keys I have unless someone turns up real quick with those.

Meanwhile the breath controller was full on.  I pulled it apart.  Some 
cracked rubber around the outer part...and I'm not sure what I'm looking 
at here.  Maybe someone will have an idea.  THe circuit board under 
where this thing screws down on...it's just two insulated rectangular 
trace blocks separated by maybe 1mm.  Stuck over the top was a piece of 
conductive foil and an impression matching it's orientation on the 
rubber diaphram that I had just removed.  I assumed that it came unglued 
from the diaphram and got stuck down there.  But...hmm..looked like some 
kind of adhesive holding it there!  Minute variations in capacitance?   
Anyone seen this type of device before? -Bob

Bob Weigel wrote:

> I got ahold of some dpdt rotary switches from ALl electronics.  They 
> height was PERFECT!  They substitute for those weird 14 pin french 
> switches that were in there after hard wiring them  and just bending 
> the lugs out sideways.
> These synths are very cool sounding.  The organ presets are great! And 
> I like strings better than trilogy at least I think. Fairly elaborate 
> BBD useage.  to create some decent roto effect for the day.  Some 
> really nice layering possibilities I already hear.  Synth part is two 
> Curtis chip channels for a mono and a paraphonic poly.  Great tone 
> qualities.
>
> Only one problem remains ..well two
>
> 1) The keys are the same fatar design used in Siel DK600, DK80 and 
> some other Crumars I think...save..these have dual spring switches and 
> hence use a different piece that extends down to move those parts.  
> I'm missing 9 of them.  ANyone have a key like that in stock?  
> Longshot I know.. otherwise I have to manufacture something to 
> duplicate what that piece does...which wont' be that bad probably...
> 2) No RESONANCE!  Not sure why.  Will trace from Pin 9 on the 
> CEM3320's unless someone has a diagram for these things.
>
> -Bob
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