[sdiy] altering designs for paia 4700

[harrybissell]

Hi Richard

Since my modular still uses some 2700 modules I guess I'm qualified :^P

You CAN run a lot of non-PAiA modules from the voltages used in their
systems. Their power supplies are far from ideal... I would be more
inclined to
replace their supply with a good +/-15V and modify the PAiA modules to
use
that.

I run my 2720 VCA from +15 and ground... and I make a 'center tap' with
two resistors and capacitors.  This is necessary because the VCA control
voltage
is referenced to the 'negative' rail of the VCA... you'd want that to be
0V in a modular
system.

I'd be happy to advise what changes you'd need to make for any of the
modules, you
have but to point me to the schematics.

H^) harry

rkmoore at memphis.edu wrote:

> Hello everyone,
>
> Thanks a lot for the responses I got to a post about the large paia
> 4700/2700/8700 I got my hands on several months back.  The manuals
> from anders sponton's site have been extremely valuable in trouble
> shooting and repairing the analog and digital circuits in the
> 4700/8700.
>
> Now I'm wanting to add some different modules (namely a moog style
> filter, SSM filter, better LFO's), but there are a few issues.  All of
> this stuff runs off of -9/gnd/+9/+18 DC.  It seems like all of the
> stuff I find posted on DIY sites is +/-15 or +/-12.  I have a couple
> of extra paia power supplies and would prefer to use them if I can.
> Also, I think that the CV's in the paia are 0 to 5V instead of 0 to
> 10V.  Can I easily modify these designs to work with the power
> supplies that I have?
>
> In the end it may be better for me to go ahead and build a +/- 15V
> supply and get a FracRak or something to hold new modules.  Opinions
> and advice will be greatly appreciated.
>
> -Richard Moore