CB radio Jammer counter measure

[Mercur]

Right I have been hunting all over the place for a solution to this and haven't found one.
My problem is that during Private Paintball Games my friends and I use CB's and Some bright spark has managed to jam our Frequencies, this isn't actualy affecting anyone aside us as we are out of range f anyone else; however I was wondering if there was a counter measure for this ?
Radio Details:
Cb Uniden 2 Watt 40 channels with 104 DCS Channels on about 25 of the 40
Location Australia (W.A)
Jammer range on any channel is I think though I'm not certain to be around 5 Km
My electronics skill: 2 years NZ curriculum electronics courses so minimal at best.

 

[Nigel Goodwin]

Track where the jammer is and destroy it.

 

[Mercur]

No other options?
As annoying as it sometimes is, It does add an extra element of competition.
If there is no other option than to 'seek and destroy' how would one track it down?

 

[Nigel Goodwin]

Direction finding - for 27MHz an RF loop aerial would allow you to measure the direction.

 

[picbits]

Report it to whoever polices your radio frequencies in your country and let them sort it out legally.

I had an interesting conversation with someone the other day. He has a GM/Vauxhall car which was showing some interesting problems with the central locking system.

If he parked up outside his house, his remote locking would not work. If he parked up outside work it would work fine.

He had the car looked at by a dealer and they couldn't replicate the fault or find what it was so he asked for help on the vauxhall community. I suggested there was something in his local area that was interfering with the signal on the frequency it was operating on. He then mentioned that his cordless doorbell wasn't working properly either.

He ended up calling in Ofcom (or someone similar) who came out with a scanner/analyser and traced the "jamming" signal to one of his neighbours houses. She was using a wireless infrared remote control extender and this had gone faulty flooding the area with a 433Mhz carrier jamming a lot of the alarm systems and doorbells.

I have a similar problem with my car when I park it near the local dentist. I can lock the car with the keyfob but it won't open and sets the alarm off every time I get in the car with the key. I suspect that due to the very old Victorian houses with thick walls, some resisdents are using boosters on their wireless house alarms which is jamming a lot of the remotes.

 

[Mercur]

Okay
picbits; I'd prefer not to go into the legal area as it isn't actualy harming anyone to my knowledge and unless it does I won't take it up officially. Thanks for the anecdote by the way.

N.Goodwin; By loop areial do you literally mean hook a loop of wire into the areial port and work out the direction ?

 

[Nigel Goodwin]

Okay
picbits; I'd prefer not to go into the legal area as it isn't actualy harming anyone to my knowledge and unless it does I won't take it up officially. Thanks for the anecdote by the way.

N.Goodwin; By loop areial do you literally mean hook a loop of wire into the areial port and work out the direction ?

No, it's a tuned loop at the required frequency, it gives two null points as you rotate it. For low frequencies you can use a ferrite rod aerial, for high frequencies a yagi, but for 27MHz a loop aerial is usual.

A simple google finds loads of information:

http://users.netonecom.net/~swordman/Radio/re-loop-article.htm

 

[Mercur]

Much appreciated, thanks for the help.
By the way heres a link should anyone wish to do a similar thing.


**broken link removed**

 

[JimB]

Just one problem, I believe that CB in Australia is on UHF (462Mhz ish).

As you have 40 channels to chose from, why not just turn the knob and use another channel?
Or does the jamming gremlin follow you?

JimB

 

[Mercur]

JimB: the Gremlin as you call them; does indeed follow us and unfortunately two of us do not have DCS capable radios so we haven't bothered trying that.

 

[ericgibbs]

JimB: the Gremlin as you call them; does indeed follow us and unfortunately two of us do not have DCS capable radios so we haven't bothered trying that.

What form does the jamming take.?

 

[Mercur]

Basically it prevents any of us communicating with each other or sometimes the channel is full of white noise or static (perhaps distance is the cause of the static)
it is literally the perfect defintion for jamming'Denial of service'

 

[ericgibbs]

Basically it prevents any of us communicating with each other or sometimes the channel is full of white noise or static (perhaps distance is the cause of the static)
it is literally the perfect defintion for jamming'Denial of service'

hi,
https://www.cbradioaustralia.com.au/
https://en.wikipedia.org/wiki/UHF_CB

As a long shot, its not a dodgy transceiver being used by someone in your group.?

 

[stevez]

The jamming is likely to be illegal however enforcement is a challenge. If it's 27 mHz the signal can travel a long way if conditions are right. You might get them to minimize their jamming by convincing them that you are hunting down their jammers.

Are they able to jam all channels? If not then you might adopt some kind of plan to constantly change frequencies.

 

[Mercur]

ericgibbs; could be but I highly doubt it is intentional if that is what you mean. However the non DCS enabled ones are old so one or the other of them may be causing the problem I'll see what Removing them fro the net does.

 

[Mercur]

stevez; the frequency is UHF 477Mhz, they are able to block all channels except they don't touch the telemetry and the 'truckie' (40) channels as well as the emergency channel but so do we for obvious reasons.
Yes I am aware that the jamming is illegal but legal action is not something I or any of my mates would pursue unless it caused harm such as preventing us from getting help etc.

 

[Nigel Goodwin]

stevez; the frequency is UHF 477Mhz, they are able to block all channels except they don't touch the telemetry and the 'truckie' (40) channels as well as the emergency channel but so do we for obvious reasons.
Yes I am aware that the jamming is illegal but legal action is not something I or any of my mates would pursue unless it caused harm such as preventing us from getting help etc.

Right, if it's 477MHz a fairly small yagi aerial would do the job nicely.

 

[Mercur]

N. Goodwin; Thanks I'll see if I can buy one or if not make one.
I belive this sort of thing is a sport like Rogaining or Orienteering except with Radio signals?

 

[Nigel Goodwin]

N. Goodwin; Thanks I'll see if I can buy one or if not make one.
I belive this sort of thing is a sport like Rogaining or Orienteering except with Radio signals?

Yes, I did it many years ago on 145MHz, on a motor bike, using a collapsible yagi I built from 300 ohm balanced feeder, wooden dowel, and rubber bands!.

 

[Mercur]

N. Goodwin; roughly how large was your set up ? (I need it for 477Mhz)