DIY bluetooth jammer, bluetooth jammer - final project

Seps111 7395 6
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  • A simple but effective 2.4 GHz jammer. This module can block BT and Wi-Fi. I designed it so that the cost of its implementation was as low as possible due to the semiconductor crisis. The circuit includes a simple astable multivibrator with a square wave to saw converter for generating the VCO control signal. The 5.1V power supply is provided by the MT3608L converter, so the device can be powered by any LiPo battery, but please make sure the battery can supply at least 500mA of current, if you want to use the amplifier, the current must be at least 1A. The VCO generates the sweep signal in the range 2100-2600 MHz. The output power is about 5-10mW, you can use an amplifier if you want more range. The CHRG fields are used to charge the battery, the 5V out pad is used to connect an external device, e.g. an amplifier. The SWEEP OUT pad is used to calibrate the output wave, the ADJ potentiometer adjusts the waveform, the correct signal should look something like this:

    DIY bluetooth jammer, bluetooth jammer - final project

    To emit a signal, a biquad antenna works best, I attach a link with an interesting article on how to make it and a model for printing a 3d antenna frame


    3D printing model: https://www.thingiverse.com/thing:4734227

    DIY bluetooth jammer, bluetooth jammer - final project

    To disrupt the signal, point the jammer at the receiver, remember that the effectiveness of the interference depends on the distance between the transmitter and receiver. When the phone is 20 cm from the loudspeaker, jamming is almost impossible, but when the phone is 2 m away, the jammer can easily block the signal within a range of several to several meters.

    An example of a 1W amplifier: https://pl.aliexpress.com/item/10050023541036..._list.0.0.37e01c24IXT8Uk&gatewayAdapt=glo2pol

    Cheaper 100 mW amplifier: https://a.aliexpress.com/_EJz6Zs5

    VCO used: https://pl.aliexpress.com/item/1005002503822581.html

    You can use a model other than YSGM232508, such as SV2450 or SM2400, the pinout should look like this:

    DIY bluetooth jammer, bluetooth jammer - final project

    Schematic diagram:
    DIY bluetooth jammer, bluetooth jammer - final project

    Tile appearance:
    DIY bluetooth jammer, bluetooth jammer - final project
    DIY bluetooth jammer, bluetooth jammer - final project
    Assembly diagram:
    DIY bluetooth jammer, bluetooth jammer - final project

    Mounting holes spacing:
    DIY bluetooth jammer, bluetooth jammer - final project

    In the attachments I include the GERBER file to order the board and the list of materials (BOM), if, for example, you want a PDF file for etching or purchase a printed circuit board (boards sold out!), I invite you to a private chat.

    Please remember that interference with Wi-Fi or bluetooth is illegal, a device for private use only to block, for example, spy devices (webcam, listening loudspeaker). The author is not responsible for improper use of the jammer, post and the information contained therein solely for educational purposes.

    Cool? Ranking DIY
    About Author
    Level 3  
    Seps111 wrote 135 posts with rating 36. Live in city Kielce. Been with us since 2018 year.
  • #2
    Level 35  
    Cool design, does the wave shape strongly affect the "effectiveness" of the operation?
  • #3
    Level 3  
    The waveform should be as linear as possible, keeping in mind that the peak voltage should be at least 4 V (then the VCO adjusts to 2500 MHz). By turning the ADJ potentiometer, not only the shape but also the amplitude changes. Very steep wave slopes may cause the jammer to malfunction.
  • #4
    Level 24  
    Why did you choose the astable multivibrator? Eyes hurt from looking at this thing on T3.
    When the slider reaches the collector, the transistor ends its life.
  • #5
    Level 3  
    I chose the multivibrator because it is quite simple and cheap in construction, it works perfectly for my requirements. With this T3 you rightly noticed, a stupid oversight on my part. However, surprisingly, when I calibrated the prototype and turned the potentiometer to the minimum, it did not get damaged, there was only squeaking due to high current. It probably survived because it worked in pulses, it is switched on with a frequency of 15 kHz.
  • #6
    Level 39  
    Need a battery for power? A LiPo battery is the better choice if it's going to be small. The battery in a cylindrical housing 18650 is an even better choice, because it is capacious and gives more current than the battery in the bag.
  • #7
    Level 10  
    It works effectively above my expectations, even on a mini omnidirectional antenna, soon tests on the one recommended by the author of the project ;)