On Wed, 10 Aug 2016 06:28:06 -0700, Taxed and Spent
wrote:

On 8/10/2016 6:21 AM, DerbyDad03 wrote:
On Wednesday, August 10, 2016 at 9:11:53 AM UTC-4, Pat wrote:
On Wed, 10 Aug 2016 03:09:05 -0400, wrote:

I've always wondered how they work, and
why they dont detect cars going the opposite direction.(I assume they
work on radar). ???

Yes, they work on radar. Cars going the opposite direction DO get
detected, but they show up as going a negative speed. The built-in
software just ignores those signals and displays only positive speeds.

So I want to speed past one of those set-ups I should drive in reverse?


no, that is how you turn back your odometer before you sell the car.
Only if it is a rather old car. Most cars today with electronic
speedos will register mileage in both directions. Some even register
reverse speeds.