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[Discuss] Wire tester (like a tone tester)

Back in the days of 10BaseT coax runs with BNC T-couplers and
terminators, I used a BNC-banana plugs adapter on a cheap VOMeter to
check if visibility was to one terminator or two.  (50? if one,
broken, or 25?=2 in parallel if properly configured.)

> Now, if any of the wiring between the wall and the patch panel is a
> problem, is there similar testing gear to check on the wiring itself
> (i.e Cat 6, PoE, etc) to help validate no kinks or broken wires?

A DC voltmeter with RJ-45 modular plug on a pigtail should let you
check for PoE ?
(shouldn't that properly be an RP-45?)

I do have a pocket-size jack-checker that indicates presence of data
and if 10G or 100G if inserted into a dubious RJ45 ethernet jack. With
a RJ45 double-jack adapter (sold as cable extender?) it would report
if cable is passing data beyond the wall. Not sure if i got it at
MicroCenter or on-line. Wasn't expensive. Easily paid for itself
checking conference room jacks to see which was live !

To test for kinks, you need a Time Domain Reflectometer (or a
specialized Network diag instrument with a similar feature). A decent
old-school oscilloscope can be jerry-rigged into a TDR with very few
additional parts, you just tee the sweep into the test port and watch
for the reflection. You need to know the velocity factor to translate
from time to distance, since C=3E8m/s is only in (near)vacuum; there
are tables around.

73 de n1vux
Bill Ricker
bill.n1vux at

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