In Need of tone genertor/cable tracer

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I need to trace some cables (phone catv, ethernet) throughout a house.
An inexpensive tone generator would work but I don't have one.  Any recomme
ndations for an inexpensive one? or alternatives?  I rigged a 1.5V battery  
holder with alligator clips to be used in conjunction with a modified LED '
probe' flashlight which will work.  Looking for alternative ideas.
I did make a 'break out box' for the rj45 and rj11 sockets where needed.
Thanks
j

Re: In Need of tone genertor/cable tracer
On 2021/08/26 11:30 a.m., three_jeeps wrote:
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If you have an old portable AM radio you can whip up an electrical  
noise/spark generator that you hook to one end of the wire then track it  
through the house using the radio.

Not so many hand held radios lying around these days though...

John :-#)#

--  
(Please post followups or tech inquiries to the USENET newsgroup)
                      John's Jukes Ltd.
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Re: In Need of tone genertor/cable tracer
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At work, we have a device that works like that.  It contains a kind
of AM radio at one end and a simple "transmitter" (AM modulated generator)
for the other end.   You clip the transmit side to a cable and it is
able to detect the other end of the cable within like a 10cm (4") range.

It is intended to find connection points on MDF/LDF, network patch panels,
etc etc.

Indeed it should be possible to build something like this yourself,
or simply use a radio and a "short range AM transmitter" module.

Re: In Need of tone genertor/cable tracer
 three_jeeps wrote:
===============

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**   Did you mean * identify*  cables or find the actual path ?  

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**  What would you do if you did?  

  Why not use a AA cell and an LED ?  


......  Phil  

Re: In Need of tone genertor/cable tracer
On Thursday, August 26, 2021 at 2:30:11 PM UTC-4, three_jeeps wrote:
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https://www.homedepot.com/p/Klein-Tools-Tone-and-Probe-Tester-and-Tracer-Kit-VDV500-705/311456018

https://www.amazon.com/s?k=tone+and+probe+tester&crid39%72PA7CBL6GT&sprefix=tone+and+prombe%2Caps%2C152&ref=nb_sb_ss_sc_1_15    

No further than your local big-box and/or Amazon.  

Why go with a kluge when the real thing (and all the associated reliability thereto) is readily available?  

Peter Wieck  
Melrose Park, PA  

Re: In Need of tone genertor/cable tracer
On Friday, August 27, 2021 at 10:04:07 AM UTC-4, Peter W. wrote:
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How far would that read?

Power to my shed is underground, and I need to do some digging to fix some drainage.  it would really help to know exactly where the 220 is routed.  I suspect it's in the 6 to 8 inch deep range, given the slope, hopefully a little deeper some places.  .  

Re: In Need of tone genertor/cable tracer
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e drainage. it would really help to know exactly where the 220 is routed. I
 suspect it's in the 6 to 8 inch deep range, given the slope, hopefully a l
ittle deeper some places. .

That is a low-voltage device, not for power lines. Underground cable tracer
s are very different animals, and substantially more costly. if all you nee
d to do is 6-8" or so, borrow a decent metal detector and trace that way. Y
ou will be within inches - dig out that area by hand. In any case, do call  
your local One-Call service, it is free and often you have no idea of what  
may be down there. And they DO have the costly devices.  

Peter Wieck
Melrose Park, PA  

Re: In Need of tone genertor/cable tracer
On Saturday, August 28, 2021 at 10:45:55 AM UTC-4, Peter W. wrote:
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ome drainage. it would really help to know exactly where the 220 is routed.
 I suspect it's in the 6 to 8 inch deep range, given the slope, hopefully a
 little deeper some places. .
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ers are very different animals, and substantially more costly. if all you n
eed to do is 6-8" or so, borrow a decent metal detector and trace that way.
 You will be within inches - dig out that area by hand. In any case, do cal
l your local One-Call service, it is free and often you have no idea of wha
t may be down there. And they DO have the costly devices.
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Sorry to confuse the thread with two different applications.

My thought was that if a signal generator can put a tone on my line, I coul
d shut the breaker in the house, leave the shed dead, put the signal on the
 shed end, and trace the wire back to the house.  It seems like that should
 work if the wire is 6 inches down, maybe not if it's 18.  Or maybe those t
one generators don't work at all underground, I've never tried it.  I did b
orrow a metal detector some years ago but got inconclusive results.  Maybe  
i could rent a better one from a big box or electrical place.  I'm sure the
 there is no conduit, I hit a wire some years back that looked like UFB, so
 I know where at least one piece of it is, and it wasn't where I expected i
t.  

Re: In Need of tone genertor/cable tracer
  snipped-for-privacy@gmail.com wrote:
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** LOL -  that is  NOT what tone generators do !!  

Their job is to facilitate cable  *identification*  where multiples exist.  

OTOH  a buried mains cable reveals it *location * by the magnetic field created by all the damn AC current flowing in it !!



.....   Phil  

Re: In Need of tone genertor/cable tracer
On Sat, 28 Aug 2021 18:03:03 -0700 (PDT), Phil Allison

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This might help:
"Buyers Guide To Cable Locators"
<https://www.tigersupplies.com/LC/Buyers-Guide-To-Cable-Locators-.aspx
There are some that work at 60 Hz, but most use higher frequencies.
There's just too much interference at 60 Hz.  Also, the higher the
frequency, the higher the resolution, which translates in a more
accurately located cable.
"Successful Locating Depends on Knowing Which Frequency to Use"
<https://www.utilityproducts.com/tools-supplies/article/16003409/successful-locating-depends-on-knowing-which-frequency-to-use

More than you probably wanted to know:
"The theory of buried cable and pipe location"
<https://www.radiodetection.com/sites/default/files/Theory-Buried-pipe-manual-V10.pdf

For what it's worth, I used an RF signal generator to locate buried
cables.  The trick is to build a series resonant RF transformer
(ferrite torroid) for your choice of RF frequency.  I picked the 160
meter ham band (1.8 to 2.0Mhz), much to the irritation of the local
ham radio operators.  The generator was set to about 70% AM modulation
at 1KHz to produce a detectable tone.  The resonant transformer will
pass the RF but not the 60 Hz line frequency, thus insuring that there
is some hope that the RF generator will survive the exercise.  It also
provides an ungrounded connection to the power line, which should
prevent some types accidental electrocutions.

The difficult part was designing and building a suitable pickup coil.
I finally resorted to a ferrite rod (loopstick) antenna similar to
what is found in many SW (short wave) receivers.  
<https://www.google.com/search?q=loopstick+antenna&tbm=isch
Such a loopstick antenna a nice deep null in the antenna pattern off
the end of the rod, which makes direction finding possible.

If I were to design a cable locator today, the system would be quite
different.  The problem with using only one frequency is that various
types of dirt attenuate different frequencies differently.  Instead of
one frequency, I would use a range of frequencies (spread spectrum),
in the hope that at least one frequency will make it through the dirt
(and interference).  That's how ground penetrating radar works.
<https://ieeexplore.ieee.org/abstract/document/9381259>

The last time I had to locate some underground wiring, I was lazy and
used an acoustic method.  I made a low frequency "buzzer" that ran
from compressed air.  I shoved the air hose as far up the PVC conduit
as possible and turned on the buzzer.  With a 1 HP motor, that might
produce 200 watts of audible buzz, which should be audible at ground
level.  I used a stethoscope to locate the buried conduit.  It wasn't
very precise at locating the conduit, but good enough to provide
clearance for a backhoe trencher.

Good luck.

--  
Jeff Liebermann                 snipped-for-privacy@cruzio.com
PO Box 272      http://www.LearnByDestroying.com
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Re: In Need of tone genertor/cable tracer
On Saturday, August 28, 2021 at 9:03:05 PM UTC-4, snipped-for-privacy@gmail.com wrote:
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Thanks for pointing out the inaccuracy of my post.  My task is one of identification.  
I just bought an inexpensive one from one of the references.  I'll use my flashlight arrangement as a backup.
I did learn something from Jeff about cable locators - TY.  Will file that away as I may be doing some of that in the future.

J

Re: In Need of tone genertor/cable tracer
On Monday, August 30, 2021 at 8:47:01 PM UTC-4, three_jeeps wrote:
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e:  
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I could shut the breaker in the house, leave the shed dead, put the signal  
on the shed end, and trace the wire back to the house.  
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.  
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created by all the damn AC current flowing in it !!  
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tification.  
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flashlight arrangement as a backup.  
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 away as I may be doing some of that in the future.  
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Yes, I agree, thanks much for that link.  There was much in there that had  
not occurred to me, especially about other current sources coupling to unde
rground lines.  It seems just possible though maybe not likely that I can f
ind an AM radio or other device that will buzz a bit close to the line, and
 that the effect is larger if it's carrying a good current, worth a try any
way.  I'm pretty sure my line is shallow and maybe even DIY.  

Re: In Need of tone genertor/cable tracer
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 not occurred to me, especially about other current sources coupling to und
erground lines. It seems just possible though maybe not likely that I can f
ind an AM radio or other device that will buzz a bit close to the line, and
 that the effect is larger if it's carrying a good current, worth a try any
way. I'm pretty sure my line is shallow and maybe even DIY.

This might be possible for an acutely sensitive device - and most AM radios
 are not that. some basics, and a few assumptions first:

a) The underground cable in question is either UF cable, or several conduct
ors run in some sort of conduit. If the conduit is metallic, or otherwise s
hielded, the AM radio trick will not work.  
b) This cable is in the US, and so is single-phase, 240 V, and consists of  
two (2) hots, one (1) neutral and one (1) ground per present code. I will n
ot speculate on Euro/Aussie codes or cables.  We do know also from Phil tha
t electricity has unusual properties down under.  

So, if the goal is to locate the cable so as not to dig through it, proof-o
f-concept would suggest that if the target radio were to be placed near to  
say.... an active AC line cord inside, it should buzz. And it should start  
buzzing within 18" or more, at least. Given that most ground is at least a  
little-bit-damp, and so will do some shielding, and the depth is unknown, t
his margin is needed.  

Just a few thoughts - considering that if it were that simple, an undergrou
nd power cable tracer would be a trivial device vs. their actual cost.

Peter Wieck
Melrose Park, PA  


Re: In Need of tone genertor/cable tracer
  snipped-for-privacy@gmail.com wrote:
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**  It would be a plus to put a triac dimmer controlled load on the end of that cable run.  


.....  Phil  

Re: In Need of tone genertor/cable tracer
On Wednesday, September 1, 2021 at 5:32:47 PM UTC-4, snipped-for-privacy@gmail.com wrote:
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Dang, that's a good idea. I was thinking a heater plus a lamp with led and CFL, but the dimmer sounds good.

Re: In Need of tone genertor/cable tracer
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Re: In Need of tone genertor/cable tracer
On Sat, 28 Aug 2021 05:32:12 -0700 (PDT), Tim R

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The minimum depth of buried power cable varies from 6 inches to
perhaps 24 inches.  This might help:
<https://www.hunker.com/12271976/depth-requirements-for-buried-electrical-cable
If the power cables are inside a steel pipe, none of the RF or
induction methods of wire location will work.  However, a common metal
detector will work quite nicely at detecting the pipe.

Maybe call 811 (in the USA)?
<https://call811.com

Maybe hire an underground utility location service?
<https://www.google.com/search?q=underground+utility+location+services

--  
Jeff Liebermann                 snipped-for-privacy@cruzio.com
PO Box 272      http://www.LearnByDestroying.com
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Re: In Need of tone genertor/cable tracer
snipped-for-privacy@cruzio.com says...
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Around here you can go to miss utility on the web or call 811.  They  
only do the commercial power, phone, cable and gas.  If you have your  
own wire from the house to an outbuilding or well they will not do it.

It is a free service.  I have used them twice.  Once when I had some  
stumps ground up that had roots that extended out about 10 feet from the  
tree.  Good thing I did as the underground power cable was under a small  
tree stump so I told the grinder man to only go low enough the lawn  
mower would not hit the stump.  A year later when I had a garage bulit  
and the foundation needed to be dug.  The man only did the power line  
the 2nd time.  They were not going to come out when I filled out the web  
page, but I called them and told them I knew the power line was probably  
in the way.  They marked the power line but not the cable line.  Sure  
enough the cable line was cut as it was about 2 feet inside the garage  
foundation.  Cable people replaced it at no charge as I had called the  
utility people.



Re: In Need of tone genertor/cable tracer
https://www.harborfreight.com/cable-tracker-94181.html?_br_psugg_q=wire+tracer

$25 US

Works well tracing house wiring.
Just remember to turn off ALL circuit breakers in the mains panel.


Re: In Need of tone genertor/cable tracer
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No.  "Designed for use with telephone lines, alarm cables, computer cables, intercom lines, speaker wires, and thermostat wiring."

Not line voltage. And not for underground tracing either.

Peter Wieck
Melrose Park, PA  

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