How a Radar Jammer Can Be Made at Home

Updated on October 19, 2017

Make a Radar Transmitter at Home

This is an example of a finished radar jammer
This is an example of a finished radar jammer

Most road users wanting to make better time on the open road will arm themselves with an expensive radar detector. However this purchased gadget will not work against a gun-type radar unit, a unit in which the radar signal is not present until the highway patrol has your automobile in his sights and pulls the trigger. Then it is too late to slow down.

A better way to safely make better time is to continuously jam any signal with a radar signal of your own. When I tested with the help of a local police officer, her device displayed random numbers when I was driving towards her. Building a low-power radar transmitter is very simple.

What Is a Radar Transmitter?

When encased in the proper size resonator, a special semiconductor named a Gunn diode will transmit microwaves when hooked up to 5 to 10 volts DC. This voltage can be sourced in-car by using an 8 to 3 terminal regulator. These regulators can be picked up at almost any auto-electrical shop.

Patrol officer radars usually operate on the K band at 22 GHz, or more often than not on the X band at 10.525 GHz. Pretty much all microwave intruder alarms and motion detectors (mounted over automatic doors in supermarkets, etc.) contain a Gunn type transmitter/receiver combination that transmits about 10 milliwatts at 10.525 ghz.

These devices work perfectly as radar jammers. If you can't get any in your area write to Microwave Associates in Burlington, Mass. and ask for info on "Gunnplexers" for ham radio use.

The finished jammer can be mounted outside the automobile, in a waterproof enclosure, or on the dash. When on the open road, switch on the power.

How to Test Your Unit

Correct construction and fine-tuning your radar jammer can be difficult, if you donk't have good measuring equipment for microwaves. One simple way to test your unit is to use a conventional radar detector, preferably one that indicates which band the radar is transmitting on.

Interesting Side-Effects

Your device will not jam radar behind the automobile or to the side, so be careful when passing speed traps regardless. Something interesting to observe is that any vehicle in front of you fitted with a detector will hit their brakes as you come up to large flat objects. Their detectors are being triggered by the signal your jammer is transmitting, bouncing off objects.


Many people go through the hassle to legally beat speeding tickets and pour thousands of dollars into fines and fighting them. Why not just build this little device and avoid them altogether?


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      Gary North Carolina 9 months ago


      How can this possibly work? If using the part from Motion activated door, and then using a RADAR detector to test Jammed police Radar, then I hate to say it but other RADAR units in other police cars would be jamming each other and we know that doesnt happen. Basically we need the exact frequency that X, K and KA operate on and then build a transmitter with about 3xs the power output. Then we will be jamming Radar because the info they get back on that frequency wont be what they sent out as my signal is 3xs stronger and therefore their signal should get mixed up with mine or JAMMED. Any way you can give me the plans for building what I discribed if I get you the correct frequencies?

    • profile image

      DeeAda04 21 months ago

      Camel Toker, spoken like a true idiot

    • profile image

      drake 2 years ago

      just saw this same post on the dark web

    • profile image

      Hack 3 years ago

      No, that is an example of a gun diode with wires. Any digital gun will ignore that.

    • profile image

      Johnf378 3 years ago

      This will be a fantastic site, will you be interested in doing an interview regarding just how you designed it? If so email me! edabeeddbeek

    • profile image

      Camel Toker 4 years ago

      Exposure to Microwave Radiation is worse than a speeding ticket. So, choose wisely.

    • CarNoobz profile image

      CarNoobz 5 years ago from USA

      Haha! That's cool. Voted up

    • profile image

      Dave 5 years ago

      Ok so... where are the plans to build this????

    • profile image

      Tom 6 years ago

      This is not what i what

    • johnsams profile image

      johnsams 7 years ago

      Hi Paul, I am not sure about the sweepable jammer, but you may be able to find more info on this website cheers!

    • profile image

      paul jones 8 years ago

      ok, sounds great! but how do i go about building it? i would like to build a sweepable jammer so that i can adjust the frequencey range that it jams/transmits. any ideas?


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