Sv: Re: [sdiy] switched mode PSU design

[Daniel Araya]

>>> Tim Parkhurst <tim.parkhurst at gmail.com> 2005-08-10 22:00:53 >>>
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


I work in the broadcast industry (FM radio) and we have been using
switchers in audioequipment since the the mid 80:s. I have salvaged a
lot of switchers but i usually use linear supplys anyway since i know
how to repair and trim them correctly. 
I use two switching Schroff supplys for +/-15V and +5/+12 on my
prototype modular though, they work very well, no measurable (by me
anyway) interference.

/daniel