Sekotech ST-300 SPIDER, Руководство по эксплуатации, Страница: 49 / 68

OPERATING MANUAL
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In the main screen of the “SWITCH” mode, set the pair “3”–“4” (2.4.1.1).
Go to the main screen of the “WR” mode (“F2” button).
The screen will display band activity for the pair “3”–”4”.
Activate the automatic mode (“F2” button).
Analyze all the detected signals at АМ- and FM-demodulation, as described in 3.4.1 above.
Exit the automatic mode (“ESC” button) to the main screen of the “WIRED RECEIVER” mode.
Go to the main screen of the “SWITCH” mode (“F1” button).
Set the next two wire combination (“3”–“5”).
Go to the main screen of the “WR” mode (“F2” button).
The screen will display band activity for the pair “3”–“5”.
Activate the automatic mode (“F2” button).
Analyze all the detected signals at both АМ- and FM-demodulation, as described in 3.4.1 above.
Proceed in this manner to test all the two-wire combinations named above.
If, during such analysis, the test sound can be heard in the headphones, it means that there is
an active high-frequency transmitter in the room, attached to the line. In this event, without
changing the combination that yields the test sound output, disconnect the telephone from the
tested line. If the suspect signal is no longer heard in the headphones and disappears from the
screen, its source is in the telephone.
If, upon disconnecting the telephone, the signal is still there, that means its source is connected
to the line somewhere in the room (as correlation with the test sound is in evidence).
Digital signals not correlating with the test sound also should be treated with caution, as those
may carry data from digital (or encoding) transmitters. It is advisable to test such signals further
in the the oscilloscopic mode (2.6.4).
It should be established if the detected signal is induced externally, or its source is connected to
the tested line. To do that, without changing the combination, disconnect the line from the PBX.
If the signal disappears, its source is attached to the line. If not, the signal is an ‘induced’ one
and therefore not dangerous.
3.5. NONLINEARITY DETECTION IN A CABLE
Object of Search:
– detection of electronics electrically attached (whether in parallel or series configuration) to the
tested cable.
Operation Modes of ST300:
– “NONLINEAR JUNCTION DETECTOR” (“NL”)
– “SWITCH”.
Additional Equipment:
Short-Circuiter (23, Fig.1)
Using ST300 in the “NL” mode on a powered line is strictly forbidden!
The use of the Electronic Switch is required.
The tested line must be disconnected from any equipment at the far end. All known equipment must
be disconnected from the line.