[sdiy] Power supply idea found, need a bit of advice..........

[vitreousflux]

Makes sense,  I suppose. I'm still hoping for the best, perhaps there is
something simple I can hook up that will help them work together.

Wouldn't a few diodes and then something additional to limit overloading
them work in my favor?

I realize I'm grasping at straws here, but I *really* want to keep my SBM
power supplies cheap. I'm way over budget for my twin sbm's (currently $1200
and counting). I ordered those power supplies for $2 each. If all else fails
(read: 4 melted power supplies, burn hole clean thru the bench and singed
hair) I am only out some change, some ceiling paint and an $8 haircut...
hehehehe.


Rob



----- Original Message -----
From: "John L Marshall" <john.l.marshall at gte.net>
To: "vitreousflux" <vitreousflux at wwnet.net>; "`Synth DIY Maillist"
<synth-diy at node12b53.a2000.nl>
Sent: Sunday, April 29, 2001 2:53 AM
Subject: Re: [sdiy] Power supply idea found, need a bit of advice..........


> I prefer to use linear power supplies with audio circuits. As you mention
> switching power supplies are noisy but the switching frequency us usually
> high; 100 KHz to 1 MHz. High power amplifiers used in automobiles use
> switching power supplies. I have used these amplifiers to drive monitor
> speakers in my lab.
>
> If you use two of the power supplies together in tandem, you will have
only
> one usable output on the negative supply if the ground return line  for 5
> volts and 12 volts is common. The plus 12 volt lead from the negative
supply
> will be connected to your system ground and the ground lead will become
> negative 12 volts. Okay, I suppose that you could use the 5 volt output as
> negative 7 volts.
>
> > www.allelectronics.com
> >
> > item number CAT# PS-9505
> >
> > it's a switching power supply (so that's more noisy than linear, right?)
> >
> > Would it be feasible to connect two of these, and tap one backwards to
> > obtain -12v and -5v?
> >
> > at $2.50 each, I'd be willing to give it a shot and see just how noisy
is
> > noisy..............
> >
> >
> > Rob
> >
> >
>
>