Firstly, get in your car and drive past a cop doing radar at about 20 mph over the limit. Take real good notice of what your speedo reads as you go past him. Preferable that you use cruise control and a digital readout.
When he gives you the ticket for speeding, see if it matches your speedo reading. If it does, then you know your car speedo is 100%.
If it does not then you can calculate what your speedo reads at a certian speed.
For instance if you were doing 60mph past the Po-po and your ticket reads 62 mph, then you know you have a 2 mph variation on your speedo.
Then get your radar unit and find a long straight bit of road out of town with a large road sign on the side. Get a good run up and set your cruise control to 60 mph. Set your radar to static mode (if possbile). As you go past the sign, hit it with the radar and see what it reads. You can then use this to see if the radar is as accurate as the officer that gave you the speeding ticket.
if the radar unit you have has no static mode, you may need a friend to drive at you at 60 mph while you test the speed of your car with your radar.
Or you could try and buy some tuning forks....either way!:D
"He didn't want to tell the cop he was on his way to the Butt Pirate Palace for a little two-step with Joe-Joe during the Village People marathon." - Cat_Doc
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You can't flip it over and start again...Don't blink..." Kenny Chesney
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