BASIC OPERATIONS
57
Initial status
The scheme of connection of the device - without change.
Type of the connected cable and number of contacts - without changes.
Operations procedure
1. Set gain of 0 dB in the LFA main menu.
2. Set bias voltage of +12 V.
3. Set the tabular cursor to the row corresponding pair 3-6.
Possible results
1.
If PTS signal is heard in the headphones, an electret microphone is detected. It must be
localized using PTS.
2.
If the PTS signal is not heard when the bias voltage is applied to the cable, the polarity of
the applied voltage should be changed.
3.
If the PTS signal is heard after changing the polarity of the voltage, an electret microphone
has been detected. It must be localized using PTS.
4.
If the PTS signal is not heard when applying bias voltage (with positive and negative
polarity), there is no working electret microphone on the cable. There may be a faulty
electret microphone (or a powered-off electret microphone with autonomous power supply)
on the cable. These microphones are detected using NLJD and REF.
Recommendations
If during testing the PTS signal is heard, it is possible that the microphone is installed
directly in the telephone. In order to verify this, disconnect the device from the cable. If the
TCP signal in the headphones is gone, then the eavesdropping device is installed in the
telephone.
If a non-PTS signal is heard, it is recommended to analyze it in the OSCILLOSCOPE or
SPECTRUM ANALYZER mode.
7.2. BASIC OPERATION #2
DETECTION OF HF SIGNALS IN POWER MAINS AND LOW-CURRENT CABLES
The purpose of the basic operation
is the detection of signals of the high-frequency
transmitters using power and low-current cables for information transfer.
Objects to test:
power mains;
telephone cables;
LAN cables;
coaxial TV cables;
other low-current cables including which are not operated, disconnected from terminal
units and/or illegally laid.
The used device - WR
