BASIC OPERATIONS
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7.5. BASIC OPERATION #5
LOCALIZATION OF THE DETECTED EAVESDROPPING DEVICES
If during testing a transmission channel of the eavesdropping device is detected, it becomes
necessary to localize it.
In case of detection of uncoded transmission channel of the eavesdropping device it is possible
to define the place of its installation by means of PTS. This method of localization is called
"Acoustic method" (item 7.5.1.).
Localization of the eavesdropping device (with an encoded transmission channel) or a non-
operating eavesdropping device (containing semiconductor elements and connected to the cable)
is performed using the
or similar devices (item 7.5.2.).
7.5.1. ACOUSTIC METHOD OF LOCALIZATION
The use of the acoustic method is possible only if an uncoded transmission channel of a
eavesdropping device is detected.
To implement the method, two operators are required. One operator moves the PTS around
the room, the other operator controls the level of the received signal using ST 301.
Action with PTS:
1. Turn on PTS and reduce the volume level.
2. Slowly move PTS within the room.
Analyzer operator actions:
1. Turn on LFA or WR (depending on which device the eavesdropping device was detected).
2. Connect headphones. Listen to an acoustic background of the room.
3. Control level volume of PTS.
The installation place of the eavesdropping device will coincide with the place where the
audibility of the test sound of PTS was best.
7.5.2. LOCALIZATION BY MEANS OF ST 301 AND NLJD
By this method it is possible to localize the eavesdropping device having electronic
components.
Two operators are necessary. One irradiates the tested cable with a NLJD, another - controls
the NLJD signal level in the cable by means of the Analyzer.
At radiation by a NLJD of the electronic devices close to the tested cable, but not connected to
it the operator of a NLJD receives responses second and third harmonics, and the operator of ST
301 does not fix any signals.
If the NLJD irradiates the electronic device connected to the cable, NLJD operator fixing
nonlinearity.
The operator of ST 301 hears a characteristic signal of a NLJD in headphones.
The place where both operators detect the responses, is an installation site of the
eavesdropping device.
This method is most effective when using NLJD ST 400 "CAYMAN" in the SEARCH mode.