Triplett TVR10/100/1000 User Manual
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Main Unit’s Cable Test jack) and tracing it using The Remote Probe.
The remote Probe will emit a tone when it is close to (or touching)
the cable under test.
Note: The tone generator places a tone on a pair of wires at a time
(first 1,2 then 3,6 then 4,5 them 7,8). This is the AT&T 258A wiring
scheme. If all 4 pairs are wired, the tone will sound rather steady. If
only 1 pair is wired, the tone will only be on for 1/4 of the cycle.
Tips for tracing tones:
●
Tracing tones is usually best on wires that are disconnected from
any power source. Existing signals on lines can sometimes
interfere with the tone signal.
●
You will notice that the Main Unit’s tone generator circuitry steps
the tone from one pair to the next (i.e. “1,2” then “3,6” then “4,5”
then “7,8’). Listening to the missing gaps in the tone signal can
sometimes be helpful in understanding a problem.
●
Maximum sensitivity occurs when the tip is held parallel to
the conductors carrying the tone and the volume is high.
Caution: electrical cables carry a wide variety of signals that are
dangerous and can harm the Cable Tests jack. Telephone circuits
employ a –48V battery voltage. When ringing, voltages are much
higher (90 V RMS on top of the –48V). Also, the PoE voltage (48V)
will also harm the Cable Tests jack, so please exercise caution. If you
are unsure of safe procedures, do not continue.
Determining the pairs that are wired. Once the cable has been
located by tracing the tone, the Remote Probe’s RJ45 jack is used
to test the wiring of the cable. The Remote Probe decodes the wiring
data sent by the TVR1000 Main Unit’s Cable Test jack (the
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