>>>>Yeah, they're radar, aren't they, and work on the Doppler Effect principle. The hand-held, multi-directional ones are called, I think, Vascar.
>>>
>>>
>>> Vascar has nothing to do with radar. It's a simple time vs distance measurement to determine speed.
>>>
>>>http://www.vascarplus.com/Pages/How_it_works.htm
>>
>>I always thought the hand-held "guns" that the UK police used were Vascar.
>>
>>While on the subject, do your police use a "breathalyser" to test DUI of alcohol - a gizmo that you blow into that registers the blood-alcohol level? Whenever I see progs like "The world's scariest police videsos" (or whatever), the troopers/traffic cops always seem to be farting around with the "sobriety test": standing on 1 leg, reciting the alphabet, walking a straight line, etc., but I never see the motorist blowing into anything.
>
>No personal experience, but I believe they do. The police usually don't go that far unless you can't pass the "field sobriety" test of normal functionality. The breathalyser usually comes after you've been arrested for suspicion of DUI, I'd presume.

Strange - all that palarver when a simple blow into the m/c will give the result.
Mind you, it makes good TV! :-)

"... don't go that far"? - it's not as if the police draw a blood or urine sample at the scene! :-)

Mind you (again) it was possible to circumnavigate the results with the old system (where you blew into and inflated a bag, and turned crystals green if over the limit) by hyperventilating for c. 30 seconds prior. I've seen this done by a guy who was defo over the limit.