Dennis Gearon wrote:
>The cops measure speed with a radar. What they do is use a non linear
>xtal to mix the incoming with the outgoing reference. It outputs RF from
>the mixing! The rest is easy. Laser doesn't work as well in bad
>conditions, but your target selection is more accurate.


Non-linear xtal .. nifty!  Not that I really understand yet, but it sounds
cool anyway.

Hmm... does anyone know how laser works?

Ken