Then, sweep around the phone and its lines while watching the meter and listening to the
click rate. If these increase, hang up the phone. If they then decrease, you’ve got a pretty
good clue that you need to do some more checking. At this point, you would conduct a
physical search of the phone and phone line.
VEHICLES
While voice bugs can be installed in a vehicle, probably the most common type is the
tracking transmitter (bumper beeper). Most of these are the burst type which means that RF
is transmitted in short bursts rather than continuously.
These transmitters can be powered either by their own battery pack or by the vehicle
battery. The ones powered by the vehicle battery can have a much higher output power
and, of course, a longer useful life. The main advantage of the battery pack unit is that it is
very easy to attach.
To check a vehicle for bugs, turn the ignition on, but don’t start the engine. (Ignition noise
will thoroughly confuse the TD-53). Sweep around, under and inside the vehicle with the
probe.
Because of the limited brightness of the indicator LEDs, it would be better to do this away
from direct sunlight, if possible. Pay particular attention to the meter. Brief flashing at the
next higher level could indicate a bumper beeper.
SUMMARY & LIMITATIONS
The best way to become proficient with the TD-53 is to practice. A reasonable and readily
available practice transmitter is a child’s 49 MHz walkie-talkie sold by Radio Shack for $10
to $20 depending on the model.
For the most effective practice, get someone to hide the transmitter for you. The person
hiding the transmitter should be reasonable. As a practical matter, a spy is not going to hide
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