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Current Tracer - for findinding shorts in a PCB

Note that the above web page says "Locate Electrical Shorts on Circuit Boards" near the top of the page.

The last remaining one I have hidden from the visiting kids is marked

25-30C. It's about right for testing PCB heating. If unavailable, the next lower range might be better. Note that you're not going to see much linear range in temperature indication. There is a rather abrupt transition at some temperature in the range. Areas of the board that are hot are bright blue. Most everything else is black. In between is a smear of red and green. If there's an air gap between the board and the liquid crystal sheet, the affected area grows rapidly larger and is difficult to pinpoint. At that point, I would suggest using a IR gun type thermometer.

There are other sources for less $$$.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com               jeffl@cruzio.com
# http://www.LearnByDestroying.com               AE6KS
Reply to
Jeff Liebermann
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So as it is a populated board, how do you know it is a in-board short and not a shorted VTS , if SM can look very inniocent, or something similar?

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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Reply to
N_Cook

In fact I found the shorted component was a surface mount diode connected directly across the capacitor on the reverse of the board, which I've replaced. Now to connect it all up again and see if everything's working again...

Alan

Reply to
Scrim

And not one word about how you went about identifying the diode?

Dave

Reply to
DaveC

connected

So a TVS, but uni or bipolar ? and what caused the high A-t transient to knock it out ? or it will likely reoccur

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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Reply to
N_Cook

Good point, sorry! I used an old HP 546A Logic Pulser and an HP 547A Current Tracer. Designed for use with logic circuits, but perfect for this job. You can pick them up quite cheaply on eBay sometimes. Superb bit of kit, except the labels - don't try to peel the plastic layer off. It looks like that protective peel off plastic, but it's not!

Alan

Reply to
Scrim

I can only try to fix what I can and hope for the best...

Alan

Reply to
Scrim

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