Path: utzoo!utgpu!watserv1!watmath!att!cbnewsl!clyde!feg
From: feg@clyde.ATT.COM (Forrest Gehrke,2C-119,7239,ATTBL)
Newsgroups: sci.electronics
Subject: Re: Radar gun zapper: fact or fiction?
Message-ID: <3488@cbnewsl.ATT.COM>
Date: 4 Jan 90 17:36:30 GMT
References: <74719@psuecl.bitnet> <1198@ariel.unm.edu> <10657@ucsd.Edu>
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Reply-To: feg@clyde.ATT.COM
Organization: AT&T Bell Laboratories
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In article <10657@ucsd.Edu>, brian@ucsd.Edu (Brian Kantor) writes:
> A reasonably large magnetron feeding a reasonably large antenna on the
> front of your car, wired up to a bank of capacitors charged by an
> inverter from the car battery, might be able to emit a pulse of 10 GHz
> or 24 GHz of sufficient magnitude to blow the mixer diode in the typical
> cop radar to glory-be.  You'd clearly want to have it trigger off the
> radar detector mounted next to it, but shielded from it in some way.


There are a few problems with this: Discharging a bank of capacitors
results in only a single pulse of energy whose average may not be
particularly high, but whose duration may be too long for most
pulsed type maggies.  Secondly, that voltage has to quite high
(most pulsed type maggies are measured in kv). Thirdly, the
heater voltage for the cathode would have to be on continuously
and the life of these tubes is not particularly outstanding.
Most of the surplus maggies in the X band range are pulsed
type and it might be a better idea to actually arrange to
pulse them with a train of pulses.  The 2J42 would be a good
candidate and probably fairly cheap.  As for K band, even a 
surplus maggie might be out of sight for cost.

Probably a lot cheaper to buy an Escort fuzzbuster (;-))

I have often thought of going the spoofing ECM route: get hold
of a small X band TWT and arrange to retransmit the radar
information back to the radar receiver, but having first
processed that information to make it look like your are
moving 25 mph.  That should make an interesting sight to
see the jaws drop as you glide by at 90 mph!

Forrest Gehrke clyde!feg