getting back to the original question.
jammers are for lazer.you get a chance to slow as when they are targeted they beep beep to warn you to slow.cop gets ********* on his read out.this give you time to slow,unit then switchs off to avoid detection ,he takes a second reading and gets you hopfully with in the limit.
if your the only car on the road he will probally know its you jammin but if there are other car he wont know who did it.
one type over here is sold as a garage door opener and has a handy side effect of blocker lazer.you will need to prove you have elec garage doors if brought to court tho

rob