On Sun, 04 Jan 2004 03:18:07 GMT, Larry W4CSC wrote:

....snip

Junk it. I did mine. If that damned series pass transistor ever
shorts, you can kiss all your equipment hooked to it good bye when the
20-some volts hits them.

You probably know this, but you can (actually, must) prevent that happening
by putting a "crowbar" circuit across the output, after the fuse. This is
just a large scr with a resistor from the bus to the gate with a 14 or 15
volt zener to ground. It doesn't conduct until the voltage exceeds the
zener limit and then the scr shorts to ground, blowing the fuse and
protecting the equipment.
--

Larry W1HJF
email is rapp at lmr dot com