Radar Detector Detectors.

In some countries or areas around the world, see the list below, using a radar detector / laser detector or even just having one on or in the vehicle has been declared illegal. This can result in the device being confiscated or the user/owner being fined or even both.

Radar detectors are built around a superheterodyne receiver, and its local oscillator emits at least some radio signal that is approximately 10MHz above the radar frequency that it is trying to detect.

This means that it is possible to build a radar detector detector that can seek out the radar detector being used. Some Police radar guns have these devices built into them. On the other side (because it also uses a superheterodyne receiver) it then becomes possible to detect the radar detector detector because it is also emitting a radio signal of a given frequency. So then you have a radar detector detector detector. Are you still with us ?

The better radar detectors such as the Bel 550 and Bel 966 have this circuitry built in. This means that if they detect that the radar gun has a detector detector it will immediately shut down to prevent the Police radar gun from detecting the radar detector.

Talk about electronic warfare!

At the time of writing 06-09-2006 these countries are known to have issues with the legality of radar detectors check locally if they are actually illegal and the local penalties.

Australia
Canada
France
Germany
Taiwan
United States
Spain
Switzerland