900 Mhz Frequency Hopping Spread Spectrum radios. Anyone try these ?
http://www.trisquare.us/images/media...talTwo-Way.pdf
Be a great way to have car to car clandestine chat.
900 Mhz Frequency Hopping Spread Spectrum radios. Anyone try these ?
http://www.trisquare.us/images/media...talTwo-Way.pdf
Be a great way to have car to car clandestine chat.
are you sure it's been defeated? many threads on RR that it's untrackable.
FWIW, it uses the ISM band
Yes certainly the feds could defeat it but nobody outside Military or CIA sorts
would have the gear to do it. It will certainly stand the test in a civilian
environment.
Sound like fun toys.
Here is an example of an interceptor..
The frequency-hopping interceptors are special advanced reconnaissance wideband receivers capable of simultaneously tracking a large number of frequency-hopping encrypted transmissions even in high background noise environments.
An example of such a reconnaissance device would be the FH-1 frequency-hopping interceptor manufactured by VIDEOTON-MECHLABOR Manufacturing and Development Ltd of Hungary. The FH-1 frequency-hopping interceptor is a modern reconnaissance system based on parallel signal processing technology.
The equipment has 160 independent receiving channels covering a 4 MHz wide IF band with 25 kHz channel spacing, 60 dB channel selection and 60 dB intermodulation suppression. The 4 MHz wide IF band is the IF output of a special high-speed front-end receiver which has a 20 to 1,000 MHz frequency range.
The digitized output signals of the channels are multiplexed and fed as 1 Mbits/s data to a fast dedicated signal-processing computer. As the processing time of the 160 channels is 200 µs with the front-end receiver 4 MHz frequency setting time, the processing speed of this interceptor is 4 MHz/200 µs or 20 GHz/s. This high speed makes it possible to process the complete 30 to 80 MHz ground-to-ground VHF band within a 2.5 ms time slot.
The system's processing algorithm filters out noise spikes and stationary transmissions and in this way hopping transmissions can be classified either in the traditional frequency versus amplitude mode or in a waterfall-like frequency versus time display mode. Optional software modules are available for direction-finding the FH transmission and for controlling a remote follower/jammer.
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yes.
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