Can a probe and tone generator trace cables behind a drywall?

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Can they be used to trace cat 5 cables behind drywalls?

 

I didn't see any replies either, so I just checked it. My conclusion is
that if the cable is touching the drywall on the other side from you,
you'll hear it fine. If, however, it's the full 3.5" away that it might
be (assuming a 2x4 behind the drywall), tracing it will be a much more
questionable proposition.

 

here is one:
http://www.testequipmentdepot.com/AEMC/CableTesters/tr02.htm

 

First off, you should've asked thie on the more appropriate
comp.dcom.cabling newsgroup.

Cat5 cabling is so tightly twisted that if you connect the toner to a
single pair, you'll get nothing when the probe is right next to it. So
you have to connect one wire of the toner to one pair or one wire of one
pair, and the other wire of the toner to another pair or wire of another
pair. Try it and you'll see what I mean.

I have one probe that has a volume control and can be turned up, so it
will make enough noise to detect fairly far away - some probes don't
have a volume control. But it depends on what's around the cabling, how
new the battery in the toner is, etc. The toner will operate on a
battery that's down to just a few volts, so check it occasionally with a
DMM and replace it when it's below 7.5V.

 

This is true not the same pair. I have the older version of Fox and
Hound by Triplett (got it at a garage sale for a couple bucks):
http://www.lashen.com/vendors/triplett/fox_hound.asp
The leads to be traced can't be grounded or connected. I have been
able to trace Cat-5 cables by just waving the probe within a couple of
feet of cables on the surface. I also found the position of 2 cables
that I fished into a lathe and plaster wall from another floor (not in
conduit). Drilled a 1/4 inch hole and fished them out with a hooked
wire. Nice and neat.

Richard

 

Or connect one end of the tone generator to one wire of the twisted
pair, and run the other end of the generator to another jack in the
house (connecting to the same wire on the cable) via an external wire
(which would have to be spaced sufficiently from the wall to keep from
distorting your response). In this case, if the length of cable you
are tracking is included in your circuit, then you should get a good
strong response(?). Just an idea.

Sam B.

 

You must have thick plastering for the lathe not to show up poking out
of the wall!

 

Was it a wood lathe or a metal lathe?

 

Made out of wood; that is wht it was so hard to find..

 

The lathe or the lath?

 

Jeez I didn't know this was a spelling test. Well I actually do have a
metal lathe. It's only 8 " between centers and it would fit into a
lath and plaster wall. Sorry for the misspelling my spell checker
doesn't check context. It does seem to be a common missuse:
http://www.google.com/search?hl=en&lr=&ie=ISO-8859-1&q=Plaster+and+Lathe&btnG=Search

More on the subject l just used my kids metal detector to trace a live
bx in a ceiling to determine that it just ended in the middle of
nowhere (bare wires with old tape). So I was able to eliminate it and
terminate the the wiring in the box.

 

You are going to *kill* the wire?? In a *box*?

G R O S S !