RE: Radar

[Thi VanAusdal <tvanausdal@xxxxxxxxxxxxx>]

Policeman John F. said:
> A Digest member said:
> >By the time you get done with this you can ask How many cars where on
the
> >road at the time he got you with the radar and H he is positive it
was you
> >that the RADAR picked up?  None of this will work if you are going 40
> >faster than everyone else.
> 
> and?  I am sure you know that the radar will pick up the 
> target moving the fastest.  This changes at great distances,
especially when 
> there are other
> vehicles with considerably more mass, (ie I may not pick up a speeding
> motorcyclye until it is much closer than the cars it is 
> approaching with,
> likewise I may not pick up a car at a great distance when it 
> is surrounded by 18 wheelers.

That goes against everything I've ever heard about police radar.
I was always taught the reading is for the STRONGEST signal.
Otherwise we'd get the reading of your electric engine fan, or a
vibrating pager, and we could all put pinweels on our front bumpers
and they'd read that value and we'd get off! 
 "But Your Honor, my 2002 won't GO 140 mph."  (not since I blew up the
 7000 rpm turbomotor ... with my wife, Morgan Fairchild, riding shotgun)

And an 18-wheeler has a radar profile of many times that of my sedan,
and many more times that of a Ninja (motorcylce or person).  The radar
gun
sends out a radar signal at a frequency H, and reads the return spectrum
for
signals at H+_S (S is the Doppler shift).  It must decide which return
signal
to display.  The 8 dB signal reflected off that semi coming at 55 mph
800 ft 
away?  The 7 db signal off that BMW going 80 mph at 200 ft (and
apparently
ot paying attention!)?  Or the .5 db signal from your own heater blower
fan
spinning the equivalent of 110 mph?  C'mon, it's the strongest signal,
not
the highest speed value!  If you go with a complex algorithm for
determining
acceptable speed and signal strength values, you remove some of the 
operator's ability to interpret the reading during use.  Keep it simple,
display the strongest signal, and let the operator do the rest.

> This, however is where training and experience comes into play.
Everyone
> needs to understand, that radar is only used to confirm a visual speed
> estimate made by an officer.  Not to say that this is the case in
other
> states, but this is how things work in California.  Personally, I
would not
> compromise my integrity for the sake of writting a speeding ticket, by
> saying I made a visual speed estimate, if I had not.  But 
> that is just me.

I agree with this.  Every time I'd ever been in traffic court getting my
rectum aerated, the officer has stated he made a visual speed
estimation,
then clocked via radar.  That 

> Then again, I am a simple guy...
> 
> John

John has graciously added to this commentary.  

 - Thi VanAusdal

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