Thread: Radar Sentry
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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default Radar Sentry

wrote in news:897efd44-c79b-4335-95de-
:

I purchased one of these from Ebay:

http://www.guysoflidar.com/museum/th...mercial-radar-
detector...

They show up occasionally on Ebay; first manufactured in 1961, when
the police in some states were use X-band radar to detect speeding
vehicles. They may not be sufficiently sensitive to pickup a ships
radar in time to be of any use, but at $20 they are worth testing
versus the $500 C.A.R.D.

Cheers, Jim


Be informed those old units radiated like hell and will JAM anyone's
radar that picks up the stray X-band radiation from them. When their
radar scanner points in your direction, they will see a sectorized blob
from its CW Xband output blanking out your radar return so they cannot
see where you are. This radiation is caused by the poorly designed
local oscillator in the old X-band radar detector's waveguide cavity, a
Gunn Diode on approximately 10.525 Ghz.....

The jamming will make you invisible or nearly invisible when you are
close to the radar equipped boat....when he needs to see you the most.

Radio Shack used to sell an X-band radar detector that is quite large,
has an octagonal black metal case with two knobs and a big red light on
it. It made such a great radar jammer for the cops, the FCC stepped in
from law enforcement complaints against it and forced RS to stop its
sale. I have one, just for grins...(c;

Cops use Ku (24.5 Ghz) band for more accuracy, smaller stealthy antennas
or laser scanners, now.

By the way, the magnetron out of a Raytheon Pathfinder (AN/SPS-21 in the
Navy) made an excellent radar jammer for the old "Speedmeter" analog cop
radars on X-band back in the 60's. Speedmeters had a silver transceiver
that hung out the left rear window of cop cars with the flat side
pointed forward. Coupled with a stock 27db feed horn, the 1KW peak
power magnetron would blow the mixer diode clean out of the Speedmeter
as you passed by him pulsing 1KW into the 27 db feedhorn. His meter
pegged negative with no mixer....a failure mode...(c; I never did this,
of course, just heard of it....(c;

Why someone hasn't started marketing Taser-proof conductive clothing to
short out the HV from a taser fired at you remains a mystery to me.