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T[_6_]

On 08/10/2016 12:09 AM, wrote:
Our town recently got one of those Traffic Speed Detecting Signs, that
tell you how fast you're going. I've always wondered how they work, and
why they dont detect cars going the opposite direction.(I assume they
work on radar). I also noticed that they only have TWO digits.
Therefore, if you exceed 99mph, what does the sign do?

Last night I was in a convenvience store, when one of the local cops
walked in. That was my chance to ask him what happens if someone exceeds
99mph. His reply was "I'll give you a speeding ticket". I laughed and
said "that's what I thought you'd say". Then I said, "besides the
ticket, what would the sign do?" He said he never tried it, so he dont
know.

If a cop dont know, who does? I'm wondering if they go back to zero, or
just keep showing 99?????

We got one of them things. Ours works on Ka band radar.
They are great for checking your calibration on your
speed-o-meter. I have called the town and asked where
they have parked the thing to check on several occasions.
It also light up my radar detector, which gives me the
hint to check my cruise control.

My guess is the the display is set by a BCD (binary coded
decimal) counter and that it would just roll over at 100
to 0.