Mark Willis wrote:

> Easy;  Someone writes up a "How to run this off an AC to DC adapter,
> by adding a power socket" web page, then someone who doesn't know what
> they're doing sticks a 48VDC 300 mA power lump into that socket,
> blowing things up if not protected.  (I've seen this done, sadly;
>  Also quite often just "any handy power lump that fits" is assumed to
> work just fine, a Zener is a GOOD idea, so's the FET.)

  Zener plus 8 amp SCR.  *That* should protect it.  Salutory effect on
the power pack too!
--
  Cheers,
        Paul B.