TV | FM Jammer

- Disclaimer -
The following description can be illegal depending on how you use the device. I am not responsible for any trouble you may get in from improper use etc.


It's always fun to play jokes on people and considering how much people watch TV these days and listen to radio or iPods connected to the radio, a TV/Radio jammer is a great prank. I had tried to make a jammer when I was younger without much luck. The circuit was very unstable and very discouraging. I have since come across two jammers that both work excellently.

Here is the link to the jammer I show in this post. This is the download link for the other jammer plans that uses one IC and a variable capacitor. Both perform about the same except the IC one uses a lot less parts and is easier to construct. I decided to make the more complex jammer to see if it has any benefits over the IC version. The only benefit I can determine is that if I ever wanted to turn this jammer into and emergency transmitter, it wouldn't be all that hard. I tried it with the IC version and I was able to transmit an audio signal but it had a lot of extraneous digital noise on the signal which made it fairly pointless.


You can see in the picture at the top that it's a pretty simple setup. There is an antenna hole (attaching an antenna can make this illegal), the tuning hole and the power jack. I decided to use and coaxial power jack instead of just hard wiring the 9v battery clip. This will allow me to use an AC power source it I ever want to do some long term jamming or emergency transmitting. The small white thing is my tuning tool. If you use a metal screwdriver it throws off the tuning so I took a nylon spacer, sawed a notch in the bottom and glued a piece of a hair pin into the notch. It works quite well as a home made tuning tool. I glued the circuit board to the case with Gorilla glue and as you can tell, I went a little overboard with the glue.

- Operation -
I have cable TV but if you are sitting a few feet from the TV you can still cause some disruption on the screen with the jammer even with double shielded coax hook up cables. I haven't tried it on broadcast TV but I am sure it will completely mess it up. It is a little hard to tune and get exact since the capacitor doesn't exactly turn smoothly. FM jamming is decent but the range isn't more than about 10 feet so you have to be pretty close to the radio to accomplish anything.

Have fun and don't get in trouble.