I need help making my own signal jammer.

[unbuildpain]

I'm an up and coming magician, one of the tricks I've planned involves blocking a cellphone from making or receiving calls. The blocking device has to cover at least 2 feet from me in 360 degrees. In addition to blocking regularly used frequencies mobile phone use, it should allow me to block custom frequencies through a dial, knob, etc. The custom frequencies can be anywhere from KHz to GHz.

As a magician, I don't know anything about electronics(I can solder wires, parts, etc), so I need to know what parts will I need, do I need a PCB, their approximate prices and if I can make it portable enough to wear it on my person, how can I safeguard from any shock when worn on my body, they'll be over cloths.

 

[Audioguru]

It is illegal to jam communication signals.

 

[unbuildpain]

It is illegal to jam communication signals.

Even in my personal space?

I can buy one on Amazon without license and it will cover approximately 300 meters, so building one which will be effective up to 2 meters from me wouldn't pose any problems.

 

[Audioguru]

How to you shield your "personal space" from everybody else?

If your jammer blocks a neighbour from calling for help and dies then you will be in BIG trouble.
If your jammer or its harmonics blocks an airplane or police/ambulance communications then .....

 

[unbuildpain]

How to you shield your "personal space" from everybody else?

We are talking about radio waves not humans.

If your jammer blocks a neighbour from calling for help and dies then you will be in BIG trouble.
If your jammer or its harmonics blocks an airplane or police/ambulance communications then .....

The advertising on Amazon says it is effective up to 300 meters, they work on the principle of over powering mobile phones signal with their own, so I don't see why the same problems which affect cell phone towers can't affect them, the energy they transfer at are not as much as a cell phone towers, with walls and everything else, the effective range could only be up to a room to few rooms.

It is not like neighbors are only confined to few feet from our premises, if they experience problems in signal reception, they can walk some feet away and call anyone(including emergency services).

Airplane, police and ambulance may only experience those problems when they are within the range of the jammer, not when they are at neighbors or nearby. Highly unlikely a plane will fly so low as to experience it.

The question really asked for 2 feet, why are you conflating it? If Amazon sells it without license, I don't have to worry about disrupting others. I'm sure many places utilize it, like academic institutions, offices, etc, don't they require emergency services? How do you think they call emergency services?

 

[FvM]

The jammer will probably disturb radio services, e.g. aeronautical communication in a wider area. It can be located by administrative radio monitoring.

If Amazon sells it without license, I don't have to worry about disrupting others.

You'll be surprised how many articles sold on the internet, including Amazon, are conflicting with legal regulations. Your assumption isn't substantiated at all.

 

[unbuildpain]

The jammer will probably disturb radio services, e.g. aeronautical communication in a wider area. It can be located by administrative radio monitoring.

You'll be surprised how many articles sold on the internet, including Amazon, are conflicting with legal regulations. Your assumption isn't substantiated at all.

The original question asked for effective range of 2 feet only, highly unlikely it'll disturb neighbors, aeronautical communications, police, ambulance, etc.

Amazon doesn't sell firearms but sells these, obviously it is treated as avoidable or tolerable interference.

 

[FvM]

You need a relative large RF field strength to block a GSM receiver. Hence I guess the 2 feet limitation won't help you much to move your jammer into the legal zone. If someone has practical experience with GSM jamming, please correct me.

 

[unbuildpain]

You need a relative large RF field strength to block a GSM receiver. Hence I guess the 2 feet limitation won't help you much to move your jammer into the legal zone. If someone has practical experience with GSM jamming, please correct me.

What would be the lowest effective range?

 

[andre_luis]

Regardless of the range, a Jammer is not a type of circuit that people could talk about openly, since, at first glance, it could be scalable in power, therefore, the limit of an alleged personal and illegal use is unsure.

--- Updated Jul 12, 2020 ---

...and I could bet you have not means to measure the electromagnetic field strenght.

 

[unbuildpain]

What would be the lowest effective range?

I found that lowest effective range is 9 meters.

Regardless of the range, a Jammer is not a type of circuit that people could talk about openly, since, at first glance, it could be scalable in power, therefore, the limit of an alleged personal and illegal use is unsure.

--- Updated Jul 12, 2020 ---

...and I could bet you have not means to measure the electromagnetic field strenght.

Why? Is the equipment to measure electromagnetic field strength expensive or difficult to obtain?

 

[andre_luis]

Is the equipment to measure electromagnetic field strength expensive or difficult to obtain?

Irrelevant, as said, Jammers are illegal devices.

I found that lowest effective range is 9 meters

I dare not ask where you got such information. Anyway, you have already been informed of how sensitive this subject is; please do not insist.

 

[unbuildpain]

Irrelevant, as said, Jammers are illegal devices.

Jammers are not illegal devices, they are sold on Amazon.

I dare not ask where you got such information. Anyway, you have already been informed of how sensitive this subject is; please do not insist.

I found the information on this link:

I understand if you don't want to talk about it or if the forum is unwilling to be associated with it, but don't say it is sensitive to be not discussed on the Internet, when they are sold on Amazon and discussed on sites accessed by teenagers and children, like YouTube, etc.

 

[ZASto]

@unbuildpain, would you be so kind to drop further discussion on this matter, please

 

[unbuildpain]

@unbuildpain, would you be so kind to drop further discussion on this matter, please

If you don't want me to reply to this thread sure.