[mkm]

Is there a way to locate where the break is in a mic cable.

Possibly some kind of non contact voltage tester or something similar
for a reasonable price(under $100).

I have a number of long cables with a break in them and I would like to
locate the break and make multiple shorter cables.

Thanks
Mike

[Don Pearce[_3_]]

On Sat, 10 Dec 2016 12:42:23 -0500, mkm wrote:

Is there a way to locate where the break is in a mic cable.

Possibly some kind of non contact voltage tester or something similar
for a reasonable price(under $100).

I have a number of long cables with a break in them and I would like to
locate the break and make multiple shorter cables.

Thanks
Mike

There is an instrument called a time domain reflectometer (TDR) which
will show you the distance to the fault. Otherwise, 999 times out of
1000, the break will be close to a connector, and you can probably
find it by pushing the cable into the connector and suddenly hearing
the signal reappear.

There are not many circumstances that will break the inside of a cable
halfway along without the damage being very obvious on the outside.

d

---
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[Scott Dorsey]

mkm wrote:
Is there a way to locate where the break is in a mic cable.

It's almost always at the connector.

Possibly some kind of non contact voltage tester or something similar
for a reasonable price(under $100).

I have a number of long cables with a break in them and I would like to
locate the break and make multiple shorter cables.

Four strategies:

1. Cut off both connectors a foot from the end, and measure. They are
likely to be fine and the problems are in the connector or the last
foot of cable which gets a lot of flexing. Put new connectors on.

2. Use the capacitance tester on your ohmmeter to determine what the
capacitance of the section before the break is. Measure a cable of
the same type to figure out ohms per foot. This will get you within
a foot or two of the break (and likely it will be at the end or the
connector of course, which makes it even easier).

3. Cut the cable in half. Check each half. Put a connector on the good
half, now you have a half-length cable. The bad half... cut THAT in
half and measure the two halves. Keep going until the pieces are too
short to bother with. I'm always running out of three-foot cables so
it's nice to have a bunch fo shorties anyway.

4. Buy a "Fox and Hound" from your local electrical supply house. This is
a gadget that puts a signal on the cable and another gadget that inductively
couples to that signal. It will let you locate breaks very precisely and
while it's not really worth the trouble and expense for microphone cables,
sooner or later you will have to find a break in a wire inside a wall or
identify one black wire in a tray full of black wires and you'll be glad you
got it.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Scott Dorsey]

Don Pearce wrote:

There is an instrument called a time domain reflectometer (TDR) which
will show you the distance to the fault. Otherwise, 999 times out of
1000, the break will be close to a connector, and you can probably
find it by pushing the cable into the connector and suddenly hearing
the signal reappear.

You can make a TDR using the 1kc square wave generator on Tek scopes!
Output of the square wave generator goes to the scope input with a T
connector, the other end of the T connector goes to the cable with a
100 ohm shunt resistor to match the 110 ohm pair to the 50 ohm source.

You can look on the scope and work out the time between the leading edge
of the waveform and the reflection in nanoseconds by counting pips on
the graticule and multiplying by the timebase setting.

It is... well, it's crude as hell actually but it'll get you close enough
to the break to tell you where to start digging. And there is nothing that
impresses the white hats more than pulling a boatanchor Tek 545 out of the
back of the car...

There are not many circumstances that will break the inside of a cable
halfway along without the damage being very obvious on the outside.

Every time I have seen that it has been a manufacturing defect. But I
have seen lots and lots of installed cables over the years that somehow
got a nail run through them which nobody noticed.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[geoff]

On 11/12/2016 8:31 AM, Scott Dorsey wrote:


Every time I have seen that it has been a manufacturing defect. But I
have seen lots and lots of installed cables over the years that somehow
got a nail run through them which nobody noticed.
--scott

Don't think I've ever had a cable fault that wasn't an obvious cut or
similar, that wasn't either at the exit of the strain-relief, the
crimp/clamp/restrainty bit, or a wire fractired off the solder-cup.

Apart from actually damaged connector bodies/pins/back-shells....

geoff

[mkm]

On 12/10/2016 2:25 PM, Scott Dorsey wrote:
mkm wrote:
Is there a way to locate where the break is in a mic cable.


4. Buy a "Fox and Hound" from your local electrical supply house. This is
a gadget that puts a signal on the cable and another gadget that inductively
couples to that signal. It will let you locate breaks very precisely and
while it's not really worth the trouble and expense for microphone cables,
sooner or later you will have to find a break in a wire inside a wall or
identify one black wire in a tray full of black wires and you'll be glad you
got it.
--scott

Would this be suitable?

http://www.flukenetworks.com/datacom...Tone-and-Probe

Pro 3000 Tone and Probe Kit $70.00 at home depot.

I think that this would work but I would like some verification before
I cut myself opening the package.

Thanks Scott!

[Adrian Tuddenham[_2_]]

mkm wrote:

Is there a way to locate where the break is in a mic cable.

Possibly some kind of non contact voltage tester or something similar
for a reasonable price(under $100).

I have a number of long cables with a break in them and I would like to
locate the break and make multiple shorter cables.

Assuming your problem is an open-circuit, not a short, and the screening
on your mic leads is not super high quality:

Connect one end of the faulty conductor to a signal generator with the
shortest possible piece of wire and feed a high audio frequency (3 Kc/s
or thereabouts) into the cable at a the highest voltage the sig gen will
give. Earth all the conductors, including the faulty one, at the other
end of the cable.

Plug one end of a jack-to-jack lead into a high impedance amplifier,
such as a guitar practice amplifier, make sure the amplifier and the sig
gen earths are connected together. Now run the tip of the free jack
plug along the outside of the cable.

Unless the screening on that lead is really superb, you ought to hear
some of the high frequency audio coming through - you will probably
hear lots of other noises too, try to ignore them. The high frequency
sound will suddenly stop as you go past the break.


--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

[Scott Dorsey]

mkm wrote:
http://www.flukenetworks.com/datacom...Tone-and-Probe

Pro 3000 Tone and Probe Kit $70.00 at home depot.

I think that this would work but I would like some verification before
I cut myself opening the package.

Yeah, that is the classic "Fox and Hound." Clip it to the pin with the break
and run the hound up and down the cable.

It is an absolutely marvelous tool for tracking down unlabelled cables,
cables in walls, and so forth. It's serious overkill for your application
and I probably wouldn't even think of bothering with it for a mike cable.
But it IS a very cool tool that will find your break. (And I bet a nickel
the break is at or right near one of the connectors).
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

On Saturday, December 10, 2016 at 11:12:45 PM UTC+5:30, mkm wrote:
Is there a way to locate where the break is in a mic cable.

Possibly some kind of non contact voltage tester or something similar
for a reasonable price(under $100).

I have a number of long cables with a break in them and I would like to
locate the break and make multiple shorter cables.

Thanks
Mike

Hi Mike,

I have been using Fluke Networks Pocket Toner to detect open or short circuits, continuity, AC/DC voltage. It is very easy to install and test. It can protect up to 52 volts.Refer to this link for different models and its services - http://www.flukenetworks.com/telecom-tools/pocket-toner

Thanks,
Ryan

[[email protected]]

On Saturday, December 10, 2016 at 12:42:45 PM UTC-5, mkm wrote:
Is there a way to locate where the break is in a mic cable.

Possibly some kind of non contact voltage tester or something similar
for a reasonable price(under $100).

I have a number of long cables with a break in them and I would like to
locate the break and make multiple shorter cables.

Thanks
Mike

My guess, the break is near the end where it gets most abused, unless there's severe kinks elsewhere. If coaxial cable, grab the center conductor (both ends) with pliers and tug on it. If broken, it should easily pull out. I can't see the braided shield being damaged.

Jack

[[email protected]]

On Saturday, December 10, 2016 at 8:53:17 PM UTC-5, geoff wrote:
On 11/12/2016 8:31 AM, Scott Dorsey wrote:


Every time I have seen that it has been a manufacturing defect. But I
have seen lots and lots of installed cables over the years that somehow
got a nail run through them which nobody noticed.
--scott

Don't think I've ever had a cable fault that wasn't an obvious cut or
similar, that wasn't either at the exit of the strain-relief, the
crimp/clamp/restrainty bit, or a wire fractired off the solder-cup.

Apart from actually damaged connector bodies/pins/back-shells....

geoff

Sort of like headphone cables, breaks occur at plug or headphone entrance, where the cable takes the most abuse, tugging, bending, etc..

Jack

[Scott Dorsey]

wrote:

I have been using Fluke Networks Pocket Toner to detect open or short circu=
its, continuity, AC/DC voltage. It is very easy to install and test. It can=
protect up to 52 volts.Refer to this link for different models and its ser=
vices - http://www.flukenetworks.com/telecom-tools/pocket-toner

Is that not just a fox and hound?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

On Saturday, December 10, 2016 at 12:42:45 PM UTC-5, mkm wrote:
Is there a way to locate where the break is in a mic cable.

Possibly some kind of non contact voltage tester or something similar
for a reasonable price(under $100).

I have a number of long cables with a break in them and I would like to
locate the break and make multiple shorter cables.

Thanks
Mike

You could short on end of the cable, and at the other end apply a few thousand volts between the two conductors, and when you hear arcing and maybe see melting, you found your open! :-)

Jack