Path: utzoo!mnetor!uunet!husc6!mit-eddie!uw-beaver!cornell!rochester!ur-tut!sunybcs!boulder!hao!ames!eos!aurora!labrea!decwrl!decvax!mandrill!neoucom!wtm
From: wtm@neoucom.UUCP (Bill Mayhew)
Newsgroups: sci.electronics
Subject: Re: radar countermeasures
Message-ID: <1032@neoucom.UUCP>
Date: 2 Mar 88 13:32:41 GMT
References: <4596@pucc.Princeton.EDU> <20271@bu-cs.BU.EDU> <912@spar.SPAR.SLB.COM>
Organization: Northeastern Ohio Universities College of Medicine
Lines: 32
Summary: Just get an issue of Radio Electronics


Radio Electronics has a history of publishing quasi-legal
do-it-yourself articles, such as: a TV descrabler, Radar Gun
spoofer,...  They get away with it on the basis that the articles
are for information only and should not be used to construct
illegal devices.  Chuckle.

Two years ago, R-E published a DIY article to build a radar gun
spoofer.  They published the article supposedly for the purposes of
calibrating your own radar gun that you use to measure the speed of
your kid's softball/baseball/..? pitches.  Right!  (I guess they
never heard of something simple like a tuning fork.)

The basic operation of the circuit was a Gunnplexer that was
modulated by an audio carrier that corresponds to the doppler shift
for a given MPH.  I don't have my phyiscs book here, and I'm too
lazy to calculate it; i think it works out to 3.2 Hz per MPH.  You
simply set the modulator to the speed you want to the radar gun to
read.

I thought it was a nice touch that their sports radar gun tuner
included a relay the you could attach to the LED on a radar
detector so that you wouldn't run down the battery on the radar gun
tuner.  The idea is that the gunnplexer would only come on when
illuminated by a radar source.  Right.

If you are determined to build an illegal device like that, go to
your pulbic library and look up the specific issure of R-E in the
Reader's Guide to Periodical Literature.  I'm pretty sure it was
published within the last two years.

--Bill