How to Buy a Radar Detector

The obvious way to avoid a speeding ticket, of course, is not to speed. But where's the fun in that? Crafty manufacturers, such as Escort, Valentine, Bel-tronics and Cobra, have developed sophisticated radar detectors to keep those flashing red lights out of your rear-view mirror.

Instructions

1. Understand that radar used by law-enforcement officers works by shining microwave searchlights down the road. When your car comes into range, the beam bounces off of it. The radar antenna calculates your speed from the reflections it receives.

2. Decide where you'll mount the radar detector--to the windshield, the dash or the visor, for $50 to $100--or have it custom installed for upwards of $1,000. Where the unit is mounted significantly affects signal detection--the higher the better. Consider, too, whether you'll use it in one particular vehicle or in multiple vehicles (in which case you'll need a mount that's easy to remove).

3. Shop for a radar detector that's most appropriate for your driving habits. The greater the detector's sensitivity, the more effective it'll be. An experienced salesperson can help you determine the best detector and placement for you.

4. Look for a unit that detects a wide range of frequencies, or bands, including laser (sometimes called Lidar). Police radar guns use a variety of frequencies to clock speeders. If you want to be stealthy, look for VG-2 alert, which protects your vehicle from VG-2 radar detection and makes your detector undetectable. Check with a salesperson for the frequency in your area.

Tips & Warnings

• Radar detectors aren't foolproof. You can get false positives or be alerted too late to that radar gun behind a hill or around a bend.

• Radar detectors are illegal to use in some states and Canadian provinces, and on certain vehicles. Obey the laws wherever you drive.

• Avoid radar jammers: They're illegal and don't work.