[OT comment] Re: Doppler Ocsillation

Jerry Avins wrote:
[snip] In the early 50s, I made a "hood
ornament" that consisted of a pair of counter-rotating wind-driven pinwheels in front of a reflecting screen. The resulting Doppler indicated a speed of over 200 mph when I was going 60. That speed was so clearly ridiculous that I never got a ticket. Transmitters are illegal, but any group that wants to use radar can hardly object to a reflector.


Reminds me of a story I read when smaller police departments started using radar.

Speeder demanded trial and challenged accuracy of radar.

Prosecutor produced 'expert' witness who demonstrated calibration by reflection from a tuning fork.

Defense claimed prosecutor had proved radar was unreliable as it was evident that guy holding tuning for was NOT going 60 MPH.

Case dismissed.

I always thought the story apocryphal, but I do believe it represents some early reaction to radar.


But now you have me thinking. Could you have set it up such that Doppler said you were either standing still or perhaps going backwards?
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Relevant Pages

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