On that date, the U.S. Air Force launched the 24th Navstar satellite into orbit, completing a network of 24 satellites known as the Global Positioning System, or GPS. In the same year it is also definitely decided to authorise the world wide civilian use free of charge. With a GPS receiver that costs less than a few hundred dollars you can instantly learn your location on the planet–your latitude, longitude, and even altitude–to within a few hundred feet. Today we have GPS system running all around us. In our, cars, boats, aeroplane and in many other transportation units.
High accuracy RF system using PLL controlled VCO
High output power, equivalent power = 3.4 W
Long Jamming range 1000-2000 feets
Small zise 1″ X 1.8″ (25 mm x 46 mm)
7-12 V DC power supply, 9V battery is default
LED flash indication of operation.
Low current consumption.
Blocks all known GPS and trackers on the market today.
Simple to build and tune
The Main part of this project is a VCO, PIC16F870 and a PLL LMX2322. The PIC control the PLL through LE, Data and clock input and set the PLL to lock the VCO to the GPS frequency 1.57542 GHz. A feedback system of R4 and C7 feed the PLL with RF frequency. X1 is a VCTCXO oscillator which acts as reference frequency. It feed both the PLL and the PIC. A pot P1 is added to fine tune the output frequency. X1 is a very stable and exact oscillator. You will achieve best performance from the jammer if X1 is calibrated with a frequency counter. Still, the VCTCXO is so exact that the jammer will work even if X1 is not tuned.
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