radar detectors

[chubbs220]

Hi - I didn't know where to put this thread so I put it basically where the most were. I just bought a new 2003 corvette that is torch red. The fact that it is a torch red corvette concerns me about getting pulled over by the cops. My friend says that radar detectors are a waste of money and that car door openers can set them off. Can someone tell me how a radar detector works, what their experiences with them are, are they worth buying, etc...?

[rsxer45]

Im not a hundred percent sure on this, but I think radar guns operate under the principle of the doppler effect. A radar gun shoots beams of light waves at a moving target. When it hits the target, it reflects back with a new wavelength that depends on the speed of the moving vehicle. If the moving vehicle is moving at a high speed, the wavelength reflected will be much longer than if it were moving at slower speeds. The gun then, detects the reflected light and interprets the wavelength (taking into account the speed of the police cruiser) and determines the speed. I think this is right. I don't think radar guns operate by measuring time differences from the light exiting the gun and reentering it.
Oops, I just realized that you were talking about radar detectors and not radar guns. Well, just take into account what I previously said about how the cops' radar operates and add to that the fact that these radar guns emit certain wavengths of light with certain frequencies. A radar detector then is programmed to detect these certain frequencies (I think its like KA band, K-band, or something and few more bands) and make a noise when it detects these. If you get an older detector it will only detect some of the older bands not used often by the police.
I have a radar detector and it works great. I have never been pulled over since getting it and most of the time it warns me of a cop at least minute before I see him. However, there are occassions where a cop drives by without the dectector going off. Maybe the cop had his radar off, or maybe he had a different operating frequency? Overall, radar detectors are pretty effective at least in my experience.

[SaabJohan]

The police might also use a "laser gun". Then a radar detector will not work.

A "laser gun" measure the time for the infra red light to travel to the moving object and back. After a number of successful measurements a speed is calculated. As one example Kustoms Pro Laser II are sending 250 laserbeams per second and to get a speed value it needs 80 approved measurements.

Two manufacturers of speed meusuring equipment:
http://www.kustomsignals.com/
http://www.lasertech.com/

Devices that detect laser/radar or disturbs measurement are also illegal in some places.

[chubbs220]

Are you sure? Because Iv'e been looking at them and in the features/specifications it says stuff like laser detectors and sensors.
-And is there any difference between jammers and detectors?

[rsxer45]

Originally posted by chubbs220
Are you sure? Because Iv'e been looking at them and in the features/specifications it says stuff like laser detectors and sensors.
-And is there any difference between jammers and detectors?

Yes there is a difference though some radar detectors come with jammers built in. Jammers sends out noise on the same frequency (or laser wavelength) of the radar or laser gun and causes the gun to malfunction due to the noise. I think there are certain jammers for laser (called LIDAR, I just found out) and for radar. There are also things called diffusers that bends the reflected light around the vehicle rather than reflecting it back to the police gun.
I found some more info on the LIDAR guns too. I heard that detectors for LIDAR (laser detectors) are pretty ineffective considering the fact that the range of LIDAR is not that long. So by the time your LIDAR detector goes off, the cop will already be on your tail. So, I wouldn't recomend buying one of those detectors. Although more and more cops are using LIDAR these days instead of radar, which kind of cancels the benefits of a radar or LIDAR detector.

[911GT2]

Detectors can tell you when radar is near, jammers stop the radar from reading you.

Detectors can be illegal depending on location, but jammers are totally illegal.