• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

signal jammers

-=PEAKABOO=-

Active Member
Oct 29, 2001
642
3
28
What are some of the ways people know of building a simple signal jammer? An old radio on a car battery does not count, unless it uses a 555 timer triggered by the signal meter to key the radio for 60 seconds after the agitator keys up.
We have a real winner around us let me tell you.
 

Signal jammers are illegal. The fine folks of this forum would have no knowledge of such items.
 
I've got a schematic and .pcb files I made up last year, it does wide-band TX, most of 26, and the majority of 27 all at the same time, while staying out of adjacent ham bands.

And for anally challenged we'll just call it wide spectrum 11 meter tuning aid which runs on a single 9 volt battery for about a month, more batteries can be paralleled for extended operation.

Warning Tossing this device in a tree may cause such interference that it could render CB radios completely useless within a few hundred yards, and may be considered malicious interference! As such I suggest only using with an appropriate 50 Ohm Good-Buddy Load!

Its been about a year, so I'll have to dig up the DVD I have the files archived on.


Oh, and the nice thing is it just uses a hand full of parts, of which the most expensive is a 2N2222, If I recall correctly 2 or 3 bucks worth if you have an under stocked junk box and have to buy them all....
 
Oh; I think there are a few threads on this if you look around...

*$5 40ch/1 watt walkie-talkie from eBay; or a pair for $10
*Turn down the output to 50mw
*Disconnect speaker/mic and add resistor to maintain a load for the circuit
*Set it on the offender's ch/freq
*Extra battery pack installed so it lasts longer
*'Key it down' with several large rubber bands
*Be ready to beat a hasty retreat once it is keyed down!
*Place in nearby tree @ night so the job is stealthy
*Be certain that antenna/radio cannot be noticed
*Replace batteries every couple of days, same stealth procedure

It should affect only the party it is placed closest to. 50mw can only transmit a few hundred yards at best, and conserves battery power. Chances are, if you use another freq, he will just follow you there - so stay on the freq the walkie-talkie is set to. He should be getting a +30 S-unit reading or higher in his receive. It will make his station deaf as a post unless he changes the channel. This is why you must set it on the frequency that you want to use. It will be so weak as to not affect you or others at all - if any. You can also replace the antenna with an equivalent length wire to make it even more stealth-like; just keep it hidden...

He may well key down his station despite being jammed. There is no better way to handle him; unless there are other complaints from his neighbors. Talk to them and ask them if he is interfering with them. If he is; then help them file a complaint with the FCC. Use whatever leverage you can legally use BEFORE resorting to jamming/guerrilla tactics. If there are a few trees around him; you can be sure that he will look for it. Stealthy wins...


>I DON'T recommend doing this, and YOU WILL assume ALL RISKS<


But it's been done before...
 
I've re-rocked a 27 MHz RC transmitter with a CB crystal and replaced the antenna with wire and used 6 D cells for a battery pack with good results, but this is good for 1 channel at a time.
 
I've got a schematic and .pcb files I made up last year, it does wide-band TX, most of 26, and the majority of 27 all at the same time, while staying out of adjacent ham bands.

And for anally challenged we'll just call it wide spectrum 11 meter tuning aid which runs on a single 9 volt battery for about a month, more batteries can be paralleled for extended operation.

Warning Tossing this device in a tree may cause such interference that it could render CB radios completely useless within a few hundred yards, and may be considered malicious interference! As such I suggest only using with an appropriate 50 Ohm Good-Buddy Load!

Its been about a year, so I'll have to dig up the DVD I have the files archived on.


Oh, and the nice thing is it just uses a hand full of parts, of which the most expensive is a 2N2222, If I recall correctly 2 or 3 bucks worth if you have an under stocked junk box and have to buy them all....

a very interesting tuning aid,might be ideal for swr'ing the whole band at the one time ;) i'd certainly love to try that out :whistle::whistle:

even better with a range of a few hundred yards,i could do the f/s at the same time,plus no interference to adjoing ham bands,a bonus,lmao.
 
I have experimented with various ones over the years but never a really good one. I would like to fine an unstable or wideband oscillator circuit.
 
One thing we used to do was use the boards out of a texas star amplifier (oscillator boards) because we had like 100 of them. Modify the circuit a little, add a crystal, and there you have it.

We also used to take cobra 19s' because we had a box of them too, unlock the PLL, and the thing would jam about 26.400-27.600 or so Mhz.
 
Last edited:
Signal jammers are illegal. The fine folks of this forum would have no knowledge of such items.

...and so is running over 4 watts on Citizens band.:bdh:


I say build a extremely high powered broad-banded linear.

200S series, provides unparalleled anti-terror security and VIP protection in large sensitive locations, such as government facilities, military installations and embassies. 200S series jammers are also suitable for installation inside military shelters (operating from AC mains power).

Four models in the series provide varying levels of coverage suitable for any fixed-location installation. The most powerful model, the 203S, is capable of completely and simultaneously paralyzing all communication frequencies from 20MHz to 3000MHz, without “gaps,” at 1365 watts of total RF output power. Jamming of each frequency band can be activated or deactivated independently
 
If you mean a broadband jamming amp - that would be illegal. The kind of thing that both the DOD and the FCC would come a'runnin for - in a heartbeat!

You would have 'MIB' swarmin your QTH/10-20!

No silly, I mean a high powered Class C amplifier with emissions all over the RF spectrum!

Just spread out those coils!:wink: get a motor maul,:w00t: do a technique known as “volting”.:ohmy: Once you get the custom amp that deadkeys 2KW AM, then we can start talking. Verify that the amp is indeed splattering all over with a Oscilloscope, may have some tweaking to do to increase the splatter.

:pop:
 
No silly, I mean a high powered Class C amplifier with emissions all over the RF spectrum!

Just spread out those coils!:wink: get a motor maul,:w00t: do a technique known as “volting”.:ohmy: Once you get the custom amp that deadkeys 2KW AM, then we can start talking. Verify that the amp is indeed splattering all over with a Oscilloscope, may have some tweaking to do to increase the splatter.

:pop:

And git you some dxn done.:tongue:
 
Why not tell people how you use an oscilliscope to verify an amplifier is splattering all over the RF spectrum?

No silly, I mean a high powered Class C amplifier with emissions all over the RF spectrum!

Just spread out those coils!:wink: get a motor maul,:w00t: do a technique known as “volting”.:ohmy: Once you get the custom amp that deadkeys 2KW AM, then we can start talking. Verify that the amp is indeed splattering all over with a Oscilloscope, may have some tweaking to do to increase the splatter.

:pop:
 

dxChat
Help Users
  • No one is chatting at the moment.
  • @ BJ radionut:
    EVAN/Crawdad :love: ...runna pile-up on 6m SSB(y) W4AXW in the air
    +1
  • @ Crawdad:
    One of the few times my tiny station gets heard on 6m!:D
  • @ Galanary:
    anyone out here familiar with the Icom IC-7300 mods
  • @ Crawdad:
    7300 very nice radio, what's to hack?
  • @ kopcicle:
    The mobile version of this site just pisses me off