Localization of eavesdropping devices using ST-301 and CAYMAN non linear junction detector

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 402 "CAYMAN" in the SEARCH mode.
ST 301 operator actions:
1. Disconnect all regular devices from the cable.
2. Connect the tested cable to the Analyzer.
3. Turn on the Analyzer.
4. Turn on LFA.
5. Connect pair on which the signal of the eavesdropping device was detected (LFA or PR) or connection to the cable is revealed (NL or REF).
6. Connect headphones. Control existence of a characteristic signal of a NLJD "CAYMAN" and in case of its listening to report about it to the second operator.
NLJD operator actions:
1. Turn on a NLJD "CAYMAN" and set the search SEARCH mode.
2. Move the antenna of a NLJD along the tested cable.

More information about ST-301"SPIDER" you can find HERE and about ST-402 or ST-403 CAYMAN HERE


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