Here are the answers to some of the most common questions I hear about radar detectors:

Officer shooting PL2

Q: Why didn’t my radar detector go off when I passed a cop?

A: A radar detector is not a police car detector. It’s a radar detector. If a police officer doesn’t have a radar gun in their vehicle (and many don’t) or if they simply aren’t transmitting and clocking cars, there’s nothing for your radar detector to detect and thus it will stay silent.

Q: Why is my radar detector going off when there’s no police around?

A: There are many sources of radar that can trigger a radar detector, and a police radar gun is just one of them. Examples of other sources include automatic door openers in drugstores and grocery stores, those “your speed is” signs, as well as cars and semis with the new collision avoidance systems and blind spot monitoring systems. These collision avoidance systems that often operate on K band are becoming especially common and can be very tough to filter out.

Q: Are radar detectors legal?

A: They are legal across most of the country, except in Virginia and Washington D.C. If you’re caught in Virginia, it’s a small ticket and no points. They used to confiscate your detector, but the law has been relaxed and they no longer do that. They simply write down your RD’s serial number instead. You can read the VA law here. Radar detectors are also illegal on military bases or in any commercial truck over 10,000 pounds no matter where you drive.

Q: Are laser jammers legal?

A: They are legal in 40 out of the 50 states and are illegal in 10 including California, Colorado, Illinois, Minnesota, Oklahoma, South Carolina, Tennessee, Texas, Utah, Virginia, & Washington D.C. The penalty for getting caught with a jammer is generally along the lines of a fix-it ticket, similar to having no front plate when you need one or window tint that’s too dark. No points, no insurance hikes. So the penalty for speeding is actually far worse than the penalty for having laser jammers. Check local laws of course, this is not legal advice, yada yada yada. Now a quick note: When jammers are used correctly (slow down when shot and kill your jammers in about 3 sec and allow them to get a reading), they’ll generally have no idea and you’ll get a nice save. This is the proper way to use your jammers no matter where you drive.

Q: What’s the difference between radar detectors and radar jammers?

A: Radar detectors work by detecting radar that’s being shot up ahead of you and giving you time to adjust your speed accordingly when it’s your turn to be clocked. Radar jammers actually turn around and jam the police radar gun, preventing it from getting a reading. The thing is that unlike radar detectors, radar jammers are massively illegal. I’m talking huge financial penalties and jail time. Additionally, the radar jammers that were produced years ago don’t work well against modern radar guns and no one has made anything new to jam radar for obvious reasons. It would be a terrible business idea. 🙂 So radar detectors are cool, but radar jammers are not.

Q: What’s the difference between laser detectors and laser jammers?

A: Laser is very different than radar. With laser, you generally don’t get any warning ahead of time. It’s only when the officer specifically targets your car that your laser equipment will go off. Radar detectors have laser sensors built in, but they’re basically just ticket notifiers. Not only that, but because a laser beam is so thin, they may not even go off when you get shot. There is such a thing as scatter which is when you get a warning when a car up ahead of you gets shot due to reflections and whatnot, but this is extremely rare and not a reliable means of laser defense by any means. A better tool is a laser jammer. This is a custom installed piece of equipment that detectors when you’re being shot and then actively fires jamming pulses back at the police officer, preventing him from getting a reading. Your job is then to slow down to the speed limit and shut your jammers off as quickly as you can. 3 seconds is a good target to aim for. Many jammers even give you the option to automatically stop jamming after a few seconds which is great in the heat of the moment. Them getting no reading on a vehicle for a few seconds is not too atypical. Either way, this allows them to acquire your speed, it’s no big deal, and they’re off shooting the next car behind you.

Q: What do the different bands mean on my radar detector like X band, K band, and Ka band?

A: They’re basically referencing the different frequencies that police radar guns can operate on. X band is the oldest technology and least common and it operates around 10.5 GHz. K band is newer and operates around 24 GHz. Ka is the newest and most common and and you’ll find it on 33.8, 34.7, & 35.5 GHz. X band is only still used in a few places around the country such as OH, NJ, and some places in OR. K band is in use all over the country and unfortunately there are also quite a few sources of false alerts on K band. Ka band is a very popular frequency and there’s very few sources of false alerts so these alerts should always be taken seriously. To find out what is used in your area, click here. To learn more about the various radar bands themselves and what all that means, watch this video.

Q: Can police get my speed while they’re driving?

A: Yes. Radar guns have the ability to operate in stationary or moving mode, whether they’re driving in the same direction as you or the opposite direction. Police officers can also pace you which means they drive at the same speed as you and measure your speed by looking at their speedometer. Unlike using radar, pacing doesn’t set off radar detectors. Laser, on the other hand, can only be used when stationary.

Q: Can my speed be read when I’m behind a police car?

A: Yes. Many police officers use dual antenna radar guns, front and rear. This means that if you are driving towards a police car and then you pass him, he can change antennas by pressing a button and continue tracking you even after you pass the police car.

Q: Where’s the best place to mount my radar detector?

A: Generally the best place to mount a detector is up high by your rear view mirror. That gives it the best view of the road and thus the best performance, you can hide it behind your tint strip so it’s less visible from the outside, and it leads to a cleaner install when you hardwire the detector. There are other options as well. Watch this video to learn more about the different options, as well as their pros and cons.

Q: Which radar detector is best for me?

A: That depends on your own personal needs, preferences, and even personality. Check out my ultimate guide to buying a radar detector.

Q: Do radar detectors work? Will they actually save me from speeding tickets?

A: Yes, but not always. They work by picking up police radar when he’s clocking cars up ahead of you. You slow down before it’s your turn to get clocked and once he clocks you, no problemo. If there’s no traffic up ahead of you or he doesn’t turn on his radar gun until he sees you and decides he wants to target you, your detector will have nothing to pick up on and you will receive no advanced warning. Additionally, if he’s using some other technique to measure your speed such as a laser gun, a radar detector won’t help you.

Q: What do you recommend to someone who’s starting out?

A: A standard kit is comprised of three different things. 1) Radar detector 2) Laser jammer 3) Waze. A radar detector will protect you from radar. Here are my favorite radar detectors. Many places now also use laser. Some almost exclusively. Against laser you’ll want a good laser jammer. I recommend the AntiLaser Priority. Finally, run the free app Waze on your phone. It’s a navigation app where people can report not only traffic information and get directions, but people also report where police are positioned around town. No setup will make you totally immune to speeding tickets if you speed, but a good setup can definitely help lean the odds much more in your favor.

Q: I don’t want to spend a ton of money. Won’t an inexpensive radar detector work just as well? I understand that cheaper radar detectors won’t have 10 miles of range, but I can slow down well before then. Who needs that much range?

A: Awesome question. In ideal conditions where there’s not much to block the radar gun’s signal and the officer leaves his gun on all the time, any radar detector can save you. However, real life isn’t always ideal. A detector that can pick up a signal 10 miles away in the wide open desert may only pick up a signal a quarter of a mile away in the mountains. If an officer is using instant on (I/O) and turning his radar gun off in between vehicles he’s targeting to try and prevent radar detector users from getting advanced warning, the additional sensitivity of a higher performing detector may mean the difference between picking up an I/O shot around the bend or not. Heck even in the wide open desert, if traffic is sparse, an I/O shot 10 miles up the road may be the only warning you get, so it helps even in “easier” conditions too. In addition to raw all out performance, a higher end detector will provide you with better false alert filtering. If your detector cries wolf too much, you will begin to ignore it over time and that may come around to bite you at the worst possible moment. Again, check out my guide on the best radar detectors to figure out which good detector is for you. They are available across a variety of price ranges.

Q: How do I set up my radar detector?

A: Check out my tutorials. Note: Many detectors are very similar so you if you own a detector that I haven’t covered, you can watch a tutorial on a similar detector and apply the same principles and ideas. Many detectors are very similar, especially those made by the same manufacturer.