OTHER PROCEDURES AND EQUIPMENT
37
REI
CPM-700
OTHER PROCEDURES AND EQUIPMENT
Computers And Related Equipment
Today’s business offices contain many pieces of RF-producing equipment.
Personal computers, facsimile machines, copiers, cellular telephones, and
other devices may radiate RF energy. These devices will show some RF
levels when probed with the CPM. They may also emit VLF signals onto the
power lines.
Two kinds of problems must be solved: 1. Determine whether an
eavesdropping device is planted in those products, and 2. Prevent
sophisticated eavesdroppers from gaining information from unintentional
radiation (via the computer monitor or data I/O cables).
CATV, CCTV
Nearly every business or residence today has some type of cable system for
TV or FM stereo reception. An eavesdropper can use the cable to reverse
feed a signal out of the target area or building. To check for RF, VLF, or
audio bugging, disconnect the cable at the point the cable enters the
building and, using the RF and VLF probes, the Auxiliary Input Patch Cord,
and a DVM, look for any signal on the building side of the cable. In most
cases, there will be no signals or DC voltage present on the cable. Use a
DVM to check the incoming line for any DC voltage. Unless your system
has a power supply for a preamp (booster), the incoming line should have
no DC voltage.
Fiber Optic Bugs
Fiber optic bugs, as with wired microphones, can be extremely difficult to
find if they were installed during construction or modification. A thorough
search of any access to the target area is necessary. When the level of
threat is sufficient to warrant such high technology, proper supervision must
be provided with any modification or new construction.
Infrared Link
Infrared (IR) provides a useful transmission medium for surveillance. Its
advantages are that it is not detectable by conventional RF detectors,
directional beam, and extremely small size. Disadvantages include a
limitation to line of sight, visually clear transmission path and high current
consumption, which limits battery use. The emitter may be a wide-angle IR
diode or a narrow beam laser.