TELETECH TX 916, Руководство оператора

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pg. 9
To enable this feature, connect the PROBE leads to the
OSCILLATOR Blue test leads, either directly or via an unbroken
cable pair. Press the PROBE’s and
600 keys simultaneously
and hold them down for about 1 second until a beep is heard. This
places the OSCILLATOR into TONE mode (the
warble tone will be
produced) and causes the OSCILLATOR to sound its buzzer if
either a short circuit or a reverse polarity battery is present between
its Blue test leads. The enabled / disabled status is non-volatile and
will not change, even if the battery is removed. If enabled, the
oscillator will beep three times when it is turned on.
To disable this feature, perform a factory reset, i.e. connect the
PROBE leads to the OSCILLATOR Blue test leads, and press the
PROBE’s and keys
simultaneously and hold them down
for about 1 second until a beep is heard.
Note: When in TONE mode, the OSCILLATOR applies a nominal 4.5
V DC to the cable pair to which it is connected. This voltage is
necessary for the OSCILLATOR to be able to detect a short circuit.
4.4. OSCILLATOR MODES
The OSCILLATOR has six operating modes. The selected
operating mode is indicated by a flashing light on the
OSCILLATOR next to the mode symbol. The modes are:
Short Circuit (Without White Wire)
The OSCILLATOR tone generation is stopped and the cable line is
looped. The White lead and the Red leads are open circuit. After
disconnecting the PROBE leads from the line, the loop resistance
and ground leakage can be measured. An RFL Bridge can be used
to locate any short circuit faults on the line (See section 6.3.1, Two
Wire Test). A TDR can measure the distance to the OSCILLATOR.
Customer Exchange
600 Quiet Line – 600 Ω termination
The OSCILLATOR tone generation is disconnected and the line is
terminated with an AC coupled 600 Ω. This termination is suitable
for measuring line noise or Return Loss. The White lead and the
Red leads are open circuit. The termination is 900 Ω in regions
where this is the standard network termination.
Customer Exchange