Well, I've thought about that one before, but the problem I've always had
with the idea is that it would be too easy for even experienced users to
plug a 9V device into a 15V socket (you get the idea).  Of course, this is
possible with warts too if they use the same plug and you get them mixed
up.  Most of the devices I'm currently running from warts are not
internally regulated.  But the current situation, 1 wart per device, is
ridiculous.


JMNSHO - Martin R. Green
elimar@bigfoot.com

----------
From:   John Payson[SMTP:supercat@MCS.NET]
Sent:   Thursday, September 04, 1997 10:17 AM
To:     PICLIST@mitvma.mit.edu
Subject:        Re: PIC power supply ...

> Wall warts are indeed an economical supply for many projects, but I have
so
> many of them in behind my stereo stand (and of course, they are too wide
> for one slot on the power bar), that they almost take up more space than
> the equipment they power.

Actually, what I'd like to see would be some smaller wall warts.  Although
there have been a few that use HF transformers with optocoupled feedback
(an oscillator on the "hot" side generates a signal which is fed through
the
transformer; the oscillator adjusts itself according to feedback about the
regulated voltage) they've tended to be expensive.  What I'd like to see,
though, would be a wall wart that skipped the feedback step and simply gave
you pretty much unfiltered DC which was 18-24v peak.  The user application
could then regulate the output in whatever manner was desired (7805 plus a
resistor and a couple caps being a nice choice).  This should be cheaper
than an optocoupled feedback circuit, but would allow the wall wart to fit
in a much smaller plug than normal.

Alternatively... what if someone just produced a multi-output power supply
with output plugs suitable for use with all those appliances?  Should be
much cheaper than a foot of wall warts; smaller too.  Think that'd be at
all practical?