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TV Jammer

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pype2000

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I found a schematic for a TV Jammer. When I built the circuit nothing would happen. I was wondering if anybody had any ideas of why not or if they know of another circuit that will do the job? The schematic used a 6 volt power supply and three gates from a 7404 hex inverter. The output of the last gate ran into the input of the first and the output of this ran into the input on the second, and so on. On the last gate from pin 5 to pin 6 an adjustable cap was placed across it. I tried this on my own television and couldnt get it to work, but it uses a cable connection not an antenna. If anybody has any suggestions please let me know.

Thank You
 
I found a schematic for a TV Jammer.

What you're describing is nothing more than a noise generator. Connecting the hex inverters together gives you a simple oscillator whose frequency is largely determined by the time delay of the 7404's. Since the waveform is (more or less) a square wave, it has lots of harmonics, some of which will be within the TV band.

...it uses a cable connection not an antenna.

Here's your problem. The inverter oscillator won't produce much in the way of power. The cable connection is designed to resist external interferance, so it's doubtful that it would work at all as a "jammer".
 
...it uses a cable connection not an antenna.

Here's your problem. The inverter oscillator won't produce much in the way of power. The cable connection is designed to resist external interferance, so it's doubtful that it would work at all as a "jammer".

How would it be external interference? If its a cable connection, hes probably hooking it up to a cable terminal.
 
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He said so in the original post: "I tried this on my own television and couldnt get it to work, but it uses a cable connection not an antenna."

He says nothing about directly connecting it in place of the cable. If he replaced the cable with a set of "rabbit ears", then it may well have worked.
 
LOL you want what my mom doesnt want, a TV jammer that I have done 1000's of times.

Basically, you want a 1 or two transistor FM transmitter. Modify it so that you can transmit at a TV channel frequency.

I suggest using 0.1uH for the inductor and anything between 1 and 15pF for the capacitor.
 
i think i figured out whats wrong pype. It sounds like maybe you are using the coax cable for an antenna.

Coax cable is specifically designed to suppress radiation from the coax line (less losses). It is also designed to not accept any interference from outside the line. It is a good thing to use for feeding an antenna, but a terrible antenna, seeing as it will SUPRESS your signal instead of radiating it.

For your antenna, use a piece of wire.

BTW, you are not supposed to be posting here asking for help on something, this section is only for those who have a working circuit that they want to share with others.
 
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