robb wrote:

wrote in message
ups.com...

On Nov 7, 7:46 am, "robb" wrote:

no shorts on any of the power regulator chips 5v L387 or the
L298s

and still get 76 ohm continuity between 5v an 0v ref.

Ummm, what's wrong with that? I = E/R: 66mA. This
(static) current isn't blowing the fuse.

TM


oh yes the fuses blow.

ther were 3 bussman fuses on different lines and such and they
are all blown

right now i am trying to track down the short(S) so i ca do
better static tests on various components without removing and
then try and power the board back up and look for other problems

at least according to the advice i have recieved etc.
thanks for taking time to look and offer some help , i sorely
need it,
robb


I have an idea for you.
get your self a low voltage auto tail light lamp.
use it in place of the fuse that blows. start disconnecting
things until the lamp glows dim or not at all.
this will allow you to keep the circuit on, you can then
track down some heat traces which won't be much..
actually, you'll be able to do a volt tracking using that
method..
You might have some logic issues that is causing current
to exist only when the circuit is fired up.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5