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RE: Do jammers work? NO Audi content



SOME jammers work,some don't.  If you have an RF source more powerful than
the RADAR gun, on the proper freq, it'll work.  The signal you're
transmitting just has to be strong enough to override the X, K or Ka band
RADAR signal.  I built an X-band jammer about 15 years ago using a 100mW
10.5 Ghz GUNN diode and a 555 chip set up as an audio oscillator.

Principle is simple enough.  RADAR guns (at least the old ones) calculate
the Doppler shift between the signal they transmit and the one that is
reflected back off the object they are illuminating.  The frequency shift
difference is converted to your mph.  All you have to do is inject the
proper shift frequency onto the RF carrier at the RADAR frequency you want.
Using this method, you can make the RADAR read anything you want.  I tested
mine after I built it on an old X-band traffic unit I had given to me by a
friend who worked at the local PD.  It really did work.  The read out on the
RADAR unit was 53 mph no matter how fast, or slow I was going.

Of course these days hardly anyone uses X-band anymore, so the jammer is
pretty much useless...except to set off the RADAR detector in the cab of
that truck that's two feet from your bumper!  I've had some fun with people
who wanted to pass me.  Let them go by, hit the transmit switch, watch the
brake lights, they get brave again, pass me...hit the transmit switch..etc,
etc,etc.  Great fun ! 8-]

Since I have an amateur radio license and am authorized to transmit in the
10.5 Ghz range, I always thought I could explain to a judge that my 10.5 Ghz
"transmitter" COULD have been causing interference to the REO's RADAR.
Never had the opportunity to test that theory, though.

"Will I build one for you?" NO.  No longer have the parts, or the time.

--Kurt
NBGS/1
'89 200 TQ