“7,8’). Listening to the missing gaps in the tone signal can some-
times be helpful in understanding a problem.
Maximum sensitivity occurs when the Remote Probe’s tip is held
parallel to the conductors carrying the tone. It is normal for the
volume to change along a cable's path (volume can change as the
cable length changes; as the angle of the probe to the conductor
changes; as the signals on or around the cable).
Caution: electrical cables carry a wide variety of signals. They are
dangerous. Telephone circuits employ a –48V battery voltage. When
ringing, voltages are much higher (90 V RMS on top of the –48V).
Telephone signals should not be on the same cables as LAN signals
but exercise caution. If you are unsure of safe procedures, do not
continue.
Test example #6. Testing the cable’s pair configuration (using
the Main Unit and the Remote Probe).
No other tester provides
the ability to locate the cable (see tracing, above) and simply plug
it into the Remote Probes jack to determine its pairs configuration.
This is called the “One step” feature. Note: With this test you can
determine if your cable is straight thru or crossover; if it has inverted
pairs (cable fault); and what pairs are terminated. To test a cable's
pair configuration:
Step 1:
While leaving the far end of the cable plugged into the Main
Unit's Cable Test jack, plug the cable end you just located in test
example #5 into the Remote Probe’s RJ45 jack.
Step 2:
The LEDs on the Remote Probe will tell you the following
information about the cable:
PAIRING: If pairs “1,2” “3,6” “4,5” or “7,8” are present and are of cor-
rect polarity, the pair’s LED will light green. The Remote Probe tests
for pairing and polarity according to the AT&T 258A standard
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