🚀 go-pugleaf

In article <1990Aug25.210746.4753@zoo.toronto.edu> henry@zoo.toronto.edu
(Henry Spencer) writes:
> In article <1990Aug23.002733.1080@mentor.com> waltw@mntgfx.UUCP (Walt
> Wilson) writes:
> > ... mounting my home-made anti-collision device on the dash fits the
> > stated purpose of HAM radio.
>
> The police have no, repeat *no*, sense of humor about such things.

In the only case I know of where someone was convicted of building an
active radar jammer, the fines were in the six figure range.  That is
more than I'm willing to risk for the luxury of driving at whatever
speed I desire.  I understand that HAMs with  a `technician' license
are allowed to use some of the same frequencies used by police radar;
however, FCC rules forbid the use of the airwaves for this purpose.

I think a passive (or pseudo-passive) approach is a good alternative.  I
had an idea similar to the bicycle wheel idea recently mentioned in this
group, in fact, I had intended to someday market such a device.  What
I planned to do was build something like a weatherman's annemometer (the
gadget that measures windspeed); however, instead of using hemispherical
cups I would use corner reflectors.  This device would be mounted on my
dashboard, so there would be no problems with wind drag (but perhaps
some major problems with visibility :-).  An electric motor would cause 
the device to rotate (since there wouldn't be any wind).  I talked with
an engineer whose specialty is radar, and he felt that the device would
probably work if the reflectors were large enough.  He did't think the
reverse side of the reflectors would be a problem, since the behavior
of an inverse corner reflector is the opposite of a corner reflector,
i.e. dispersal of the reflected waves.  The corner reflectors, as viewed
by police radar, would be constantly moving backwards.  The only problem
might be police radar behind me.  It would also see the reflectors moving
away, but in this case, it would add to the relative speed.  A shield
would probably do ok her, and another device might be mounted in the
rear window to fool radar behind me.

Another idea we talked about is to build a spark gap.  The principal is
that while a spark gap isn't really a `transmitter', it does emit large
amounts of power over the entire spectrum.  My radar expert believes this
might be enough to fry the radar speed detectors front end.  Unfortunately,
it would also fry the front end of any radar detectors in the vicinity.  I
could build a spark device that was triggered by my own radar detector, and
which shorted together the input to my front end just before it fired, but
this wouldn't help the other people.  Their detector would be fried, result-
ing in a false sense of confidence and probably a speeding ticket.

Stealth techniques will probably work, but you'll have to be willing to
compromise the appearance of your vehicle.  All the RF absorbing materials
I've seen are flat black, which isn't exactly my idea of a nifty color for
sports cars.  :-)  Does anyone know if it is possible to paint over these
materials with conventional auto paints without loosing their absorbing
qualities?

As for the legalities, the spark gap may have some problems.  While it
isn't what I would consider a `transmitter', it certainly isn't passive.
I also wouldn't want to go down the road frying the radar detectors of
my fellow drivers, because I know I wouldn't want someone to do the same
to me.  I rely on my detector to help me keep a semi-clean record, and I
know many others do the same.  The corner reflector pinwheel is truly
passive; therefore I can't see how it could be deemed to be illegal.  It
might be cited for obstructing my field of vision (if it is very large)
but it certainly isn't a transmitter.  I can't see anything illegal about
the stealth technique either.  There certainly isn't any law against
painting your car, nor is there a requirement that your car have surfaces
which are orthogonal to oncoming radar waves.

Why go to all this trouble just to avoid traffic tickets?  Well, for one
thing there is alot more cost involved than just the tickets.  Insurance
rates in the USA tend to skyrocket when you get more than one ticket in
a three year period.  Enough tickets can also result in a revoked license.
I habitually exceed the speed limit, especially when I'm driving on the
interstate or other limited access highway.  I know myself to well to
assume that I'm going to change anytime soon.

I've saved alot of hassle already by religiously using a radar detector.
I turn it on anytime I start the car, even if I'm just driving down the
block.  I turn it on right as I start the car.  My model is one of those
which put out an annoying series of beeps as it performs a self test, so
I put on my seat belts while it self tests, then turn up the volume.  In
fact, using a radar detector has succeeded at doing what driving school
and all those TV commercials failed to do: get me to wear a seat belt. :-)
I think passive countermeasures is the next logical step in my defense
against police radar.  In fact, if radar detectors are banned nationwide,
passive countermeasures may be our only defense. :-(

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