The debate continues over the use of jammers – both passive and active – over whether they actually do what they are designed for or if they are a pretty piece of plastic to decorate your dash.
Basically, some of the best radar testers in the world have tested a number of the supposed ‘best’ jammers with a range of results – mainly bad! Below outlines the way that jammers are designed to work, so readers can make their own opinion before buying such products.
Radar detectors are passive devices that merely pick up the presence of a radar and alert the driver, whereas newly designed jammers are designed take an active role in messing with the signals in police equipment.
These products have a radio transmitter, which emits a jamming signal. They are supposed to block radar by mixing with and sending back a FM radio noise that confuses the radar gun’s computer.
With this information added, the radar receiver gets a confusing echo signal, and the police can't make an accurate speed reading.
Also on the market are laser jammers which work pretty much the same way as a radar jammer. This detector has its own built-in light emitting diodes that make a beam of their own. When this beam shines on the lidar system, the receiver can't recognise any reflected light and so can't get a clear speed reading.
While these products seem like the magic solution for all speeders, in actual fact, they are not! Like with radar detectors, a number of environmental factors can influence the jammers making them less-effective or ineffective. Most radar experts recommend they are used in combination with a good radar detector in order to get the best results.
As to the legality of jammers, this varies all over the world. Some passive ones are, but the majority of active jammers are prohibited in most countries. Before purchasing one, the best advice is to check the law in your state/country.