[EMAIL PROTECTED] wrote:

> Run a couple of amps (from a current limited power supply) through the short and
> use a 5 1/2 digit voltmeter on the millivolt range  and you can get the short
> circuit location fairly easily.

Yes, that's the procedure.  But, with perhaps 500 holes tied to the ground
plane, covering the whole board, the voltage drop across the planes can be REAL
small.  I ran 6.5 A between the power plane and ground, and was able to apply
about 15-20 mV between the planes.  The actual location of the short was
found at a through hole with about 2 mV difference than the neighbors.
But, there was probably 5 mV of voltage drop across the planes.  So, it had
to be compared to local pads that weren't shorted to spot the bad one.

Then, I had to burrow into the board, through 2 layers, to dig out the short
right next to a grounded pad.

Jon


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