Digital Body Wire Systems
Conventional analogue body wire systems suffer from vulnerability to
monitoring. They are also susceptible to drop-outs if the
transmitter moves out of range and temporary loss of communication
results. On the receiver side, the usage of audio cassette
recorders to record conversations is inconvenient and prone to mistakes.
The DFH-DAR-902 digital spread spectrum body wire system changes all
that by offering:
Unique TriMode(TM) modulation system (choice of three operating
modes - three devices in one!)
Digital encryption for unbeatable security
Frequency hopping spread spectrum for safety from detection
Digital audio recording in both the transmitter and receiver
Multiple receiver capability
User programmability
The Transmitter
Contained in an elegant black aluminium case,
the transmitter measures 55 x 87 x 19 mm
(2.2 x 3.4 x 0.7 inches) and works on four
standard AAA batteries. The maximum power is
400 mW. The in-built digital audio recorder
has over sixty minutes of recording capacity.
The recorded audio remains preserved even
when batteries are removed. The transmitting
function can be disabled, making it possible
to deploy the device as a solid state recorder
only.
The transmitter contains a sensitive
microphone with a connector for an external one.
There is also a serial data connector for
interfacing to the base receiver, for the purpose of
programming the transmitter and for
downloading the recorded audio.
The transmitter can operate in one of three possible modes: "hi-fi"
analog, digitally encrypted, and frequency hopping spread
spectrum. The selection between these three modes can by done by
connecting the transmitter to the receiver via a
programming cable, and selecting the mode using the receiver keypad -
simple instructions are clearly shown on the in-built
LCD display of the receiver.
In a similar way, the transmitter can be also programmed to one of three
possible power settings. This has a direct effect on the
transmission range and the battery life.
The transmitter can be also connected to the parallel port of a PC via a
special high-speed interface adaptor. This makes it
possible do download the recorded audio directly to a PC in a standard
WAV format, and play it back immediately using standard
multi-media capabilities of a PC.
The recorded audio can be also downloaded to the recording memory of the
receiver and played back from there.
http://www.sst.com.au/bodywire.htm
