DIY cell phone signal jammer

With the development and spread of mobile phones, means for reading information through GSM channels have also appeared. Various spy gadgets are currently available to cybercriminals. They allow you to connect to any telephone and read information from it. Cases of remote activation of the microphone in the phone and listening to what is happening around are also common. If you are worried about the privacy of your calls, you can assemble a silencer for your cell phone signal.

Will need

To make the device we need:

• Integrated timer chip NE555.
• Bipolar High Frequency Transistor BF495.
• Ceramic capacitor 2 pF; 7 pF; 3 pF; 47 pF; 30 pF.
• Electrolytic capacitor 1mkF, 63V.
• Resistor: 10 kOhm; 6.8 kΩ; 82 kΩ; Ohm; 6 kOhm.
• Copper wire with a cross section of 0.5 mm.
• Mini-slide switch, type SPDT.
• 3 mm LED (green).
• Two-pin plug connector.
• Crown battery connector 9 Volt.
• Battery 9 Volt.

Jammer circuit

There is nothing complicated. A high-frequency generator operating at a frequency of 50-120 MHz is assembled on the transistor. And the timer has a low-frequency square-wave generator for modulating the output radio signal.
The cell phone itself operates at a frequency of 2.4 GHz. So how does a jammer suppress a signal at such a high frequency? The fact is that the output generator does not have a bandpass filter at the output and all side harmonics are heard at all frequencies above.
There is one more trick: in fact, to be precise, the jammer does not jam the signal completely, it only interferes with the mobile phone, as a result, it cannot register on the network.

Printed circuit board

To get started, we will order or make a printed circuit board for our product on our own. You can make a printed circuit board with your own hands using laser-ironing technology.

Production of contour coils

From 0.5 mm thick copper wire, we will make three coils:

• The first is 4 turns;
• the second - 3 turns;
• the third - 15 turns.

The diameter of each coil is 5 mm.
For ease of manufacture, you can wind the wire around the tip of a screwdriver. At the first two ends of the windings we clean. The third coil will act as an antenna, so we need only one pin, we cut off the second.

Getting to the manufacture of the device

We install and solder the radio components according to the scheme.
We solder the wires from the battery connector to the contacts of the plug connector. Be sure to observe the polarity.
We connect the battery, turn on the toggle switch. A lit LED indicates muffler operation. We check the performance of the product.
After turning on, the "network is gone."

Customization

With good parts, the device starts working immediately. The only thing is that the frequency must be set with a variable capacitor at the maximum exposure distance.