I was using a Stalker Dopler hand held standing on a side road one day.
Little truck comes zooming up, I wave him over.
He proceeds to tell me I can't write him a ticket because his detector didn't go off. Basically calling me a liar saying I was guessing his speed and never turned it on. ( Radar confirms my estimate only, as I can guess your speed very acurately. )
He had a brand new everything machine worth several hundred dollars sitting on his dash, ( That never sounded off.)
I asked him if it was on, he said yes. I pointed the handheld at a passing car, pulled the trigger and it still didn't sound off. Next car went by I held the trigger for twice as long as I needed to get a reading. BINGO, his detector sounds off.
So later on to expieriment we tried quick shots with laser and two other bands in the same senario as the ticket I wrote.
Each of our radars could be used fast enough as not to be detected by the detector, strange. At longer distances it didn't work as well.
But as most people know, if Im aiming at you, forget it your caught no matter what type of radar is used. Sometimes you may pick it up on your machine, sometimes not. The radar gun has your speed before your detector sounds off anyway. So good luck jamming the brakes
( Im not covering radar jammers.)
We tried two different types of detectors that day. Sorry I don't remember the models, one was laser. Its been a few years ago so the models have changed anyway.
*PS, that black box will insure you get wrote, if I see it.