Find Short Circuits the Easy Way?

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dibbons

dibbons

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Does this work?

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That may not do what you think. It is essentially what we used to call a "toner" which we used to use for telco circuits. It is more accurately a circuit tracer rather than a "short finder."

telco toner generator tracer - Google Search

The way they typically work is the box with clip leads has a switch, either generates a tone, usually 1 of 2 selectable, or provides weak "battery" for continuity and can be used with a buttset for "talk" power. The tracer or receiver is wireless, and picks up the weak toner signal when run along a wire

I'm sure that if you do have a short, it will react differently which you could find with practice, and "open" similar
 
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A typical automotive "short finder" is an entirely different breed. These have been around in some form since "I was a kid" (born in 48). They consist of a circuit breaker with a "likely" a resistor to limit current, and a magnetic meter works like a compass. You hook the clip lead breaker unit from power to the shorted circuit, and the internal breaker starts cycling, like a flasher. This sets up an on/off magnetic field around the wire. You run the meter along the wire, and it deflects differently or not at all when you get to or pass the short. Outfits such as KD tool have made these for decades

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My circuit "toner" consists of an old RF generator tuned to an AM radio frequency and then adding a 400 hz tone to modulate the RF. Attach that to the circuit I want to trace, then I take a simple handheld AM transistor radio tuned to the aforementioned RF frequency and move it back and forth over the area where I "think" the circuit is buried (I use this on underground wiring & cables) and when I hear the 400 hz tone, I'm there. Just a little back and forth motion to find the strongest signal and then mark the ground in that spot.

Works every time, not fancy or expensive stuff. Just using tools I already have.
 
cudamike13 said:
Hey Del! Did you ever get a chance to work on sound powered phones when you were in the Navy?
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LOLOL I was never on a ship at sea. My specialty was GCA RADAR tech, got sent to NAS Miramar, sposed to be there 2 years (I was in for 6) and in 72, got extended to end of enlistment

There's nothing to sound powered phones. They are a dynamic (electromagnetic) element that generates a tiny current, and that is repeated in the 'phones' end. Damn dear as simple as a pair of tin can phones.
 
I use a non contact thermometer to find shorts. Why? What do shorts have in common with a non contact thermometer? Heat. Follow the wire and you will find the hot spot and the short.
 
I just use the audible resistance setting on a cheapo Harbor Freight voltmeter. Use it to see if your hot wires are shorted to ground.
 
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