[sdiy] switched mode PSU design

[Tim Parkhurst]

On 8/10/05, Peter Grenader <peter at buzzclick-music.com> wrote:
> just a heads up:
> 
> I've got a Buchla 259 here (analog)for repair  that's in a homebrew box
> which is powered by a single mutli-tap switcher (not a wallwart).  It's
> noisy as hell.  Replaced power with a linear - noise be gone.
> 
> - P
> 
> 
> 

You know, there has GOT to be a way to properly filter and/or shield a
switcher to keep it from goofing up audio circuits. Old PCs (with a
power supply) can be had for next to nothing, and someone really
clever (and with more spare time than I have) could take an old PC
case and make a really nifty little synth out of it. Where else could
you get a nice rugged sheet metal case AND power supply for $10 or so?
Maybe even use the motherboard as a 'backplane' to distribute signals
and to provide a nice mechanical mounting for synth modules. It sounds
to me like the toughest part would be figuring out how to quiet down
that pesky switching supply. Of course, you could just yank the
switcher, stuff in a linear supply and still use the case, but that
adds significant cost. Another method might be to 'remote mount' the
switcher supply in an external box, but there still could be noise on
the supply lines (and again, this makes the whole mess more costly and
bulky).

Any thoughts?

Tim (messy and costly, but not bulky) Servo
-- 
"Imagination is more important than knowledge." - Albert Einstein