No Subject ( camera nonsense )

[Michael Motyka]

Lucky Green wrote:
> 
> Traffic analysis is performed using wire loops in the the road. The
> sensors mountend on overpasses near truck scales fulfill a different (so
> far unknown) purpose.
> 
> --Lucky
>
The wire loops I know about use 60Hz AC and measure inductance. I 
believe that this would make them unsuitable as speed measurement
devices since measurement would extend over a number of cycles. They
might work if they were widely separated but you would have to be sure
there was only one vehicle generating the peaks.

I'd stick with the speed detector radar for now to explain the overhead
doo-dads.

m