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Uncle Monster[_3_]

wrote:
On Mon, 15 Sep 2008 04:24:22 -0500, Uncle Monster
wrote:

Jud McCranie wrote:
Our house has a buried cable that was laid by the previous owner for a
potential lamp in the yard. It is hooked to a switch in the house,
but there is nothing on the other end. Is there a way for an
electrician to find it without digging?
I've used a small battery powered radio
switched to the AM band to trace live
wires before. Tune it to a relatively
quiet section of the band and wave it
near a known live wire and listen to
the humming sound it makes. I have also
used a tone generator of the type used
for tracing telephone and network cables
in conjunction with an AM radio to trace
hidden wires. The toner produces enough
RF harmonics in the AM band that tracing
a wire is no problem. You would have to
make sure there was no power on the circuit
first before hooking up a toner.

[8~{} Uncle Monster

I agree with some of this, but there is a problem using the AM radio.
The wires need to be powered, and I would not power up a dead ended
wire under the lawn. Begin he Where is the wire exiting the
house? Look in the basement, or look for a piece of steel or pvc
conduit coming out the house. It might be near the switch. When you
find where it exits, make a straight line from the exit point on the
house to the location where the yard light should be. If you have no
idea where it should be, it's generally placed near a sidewalk or
driveway, and toward the road. (but not always). Take a string and
make a straight line to the road. Follow the string with a detector
device. You can buy those detectors for around $20 at many building
supply houses and hardware stores. With them, you do NOT power the
wires. The device uses batteries and sends the signal into the wires
at the switch or any other point in the feed. Then you carry the
other device and listen to it.

So you think the guy buried the wire for
a future light and did not cap or tape up
the ends to protect the wire from water?
I'd like to know what detector costs $20.00,
what brand is it? The toner and detector I
have costs over $100.00. The other wire and
cable finders I have are very expensive and
beyond the means of do-it-yourselfers. I
repair a lot of cable locating and telecom
equipment for a friend of mine that we put
on eBay. The older equipment is affordable
for a contractor but I doubt a home owner
would want to invest in it. Something like
a 3M Dynatel 573A sheath fault cable locator
is an older unit that could be bought for
$150-$250 in good condition. A Radio Shack
brand metal detector may work and Harbor
Freight also sells one for $50.00.

http://tinyurl.com/57aopq

[8~{} Uncle Monster