The longitudinal axis stands for the shielding radius of cell phone jammer

In the actual circuit, usually using frequency synthesizer to provide sufficient accuracy and good stability frequency. One or more of the reference frequency signal is transformed into one or more of the desired signal frequency is the frequency synthesizer technology, otherwise known as frequency synthesis technology. The basic composition of the frequency synthesizer. Handsets commonly used for the band PLL frequency synthesizer. Each frequency synthesis loop includes five basic functional circuits: reference clock oscillator, phase detector, low-pass filter, VCO and divider. Shown in Figure 4-22. Reference oscillation signal is set f1, set the VCO output signal is f2. Divider output signal is f2 / N. Purpose of the control loop is to make f1 = f2 / N. The line centralized controller of cell phone jammersystem is the relatively independent hardware case.
Reference clock oscillation circuit. Handset reference clock oscillation circuit is a very important cell phonecircuit, resulting in the 13MHz clock, while the logic circuit for the handsets provided the necessary conditions, on the other and provide the basis for the frequency synthesizer circuit clock. Cell phone13MHz reference clock circuit, there are two circuits: one dedicated 13MHzVCO components, VCO components generally have four side El: output, power supply side, AFC control terminal and ground. Figure 4-23 is the Siemens 2588 cell phone13MHzVCO circuit. Figure 4-24 is the Nokia 3310 cell phone26MHzVCO circuit. The other is by a 13MHz (26MHz, 19.5MHz) quartz crystal, integrated circuit and external components, the crystal oscillator circuit. If the antenna of cell phone blocker is also needed, please inform us of information of antenna you need timely.
Figure 4-25 is the Ericsson T28 mobile cell phone13MHz crystal oscillator circuit. By the N234 and 13MHz crystal B320, varactor diode V322, V321, etc., the circuit 13MHz signal, processed by the N234 module output two-way: the way through capacitor C300, C302 to D300 module 15 feet, to the frequency synthesizer circuit to provide reference signal; the other way 52 feet from the N234 output logic to the logic circuit provides the clock signal; 13MHz circuit module control signal VCXOCONT from the N800. Figure 4-26 is the Motorola V998 mobile cell phone26MHz oscillator circuit. From the 26MHz quartz crystal Y230, varactors CR230 and IF module U913's internal oscillator circuit is composed. In the prison, the position of cell phone jammer is relatively higher than the normal level.
Circuit, Y230 crystal is 4 feet, of which three feet are linked to a ground terminal, while the other foot is as output, AFC automatic frequency control voltage output from the U913 side of J7, U913 in J8 pin power supply side, U913 13MHz reference frequency oscillator generates a reference frequency signal source all the way to synthesize a variety of carrier frequency, the other side all the way from the J6 output of U913 to the central processor, the logic of the clock as a mobile phone. Figure 4-27 is the Samsung A188 mobile cell phone19.5MHz oscillator circuit. U101 and Y101 by the quartz crystal and other components, the resonant frequency of quartz crystal Y101 (reference frequency) is 19.5MHz, the U101 module for 1.5 times the frequency processing to get the reference signal and the frequency synthesizer logic of 13MHz clock signal. Understand distribution situation of the base station around the prison where cell phone jammer needs to be installed.
Frequency synthesizer reference signal output from the foot of C10 U101; logic clock signal output from U101 feet of H7. U101 pin power supply side of the D10. VCO components or whether the composition of the crystal oscillator circuit, the control signal needs to AFC, AFC signal from the logic circuit in the DSP (Digital Voice Processor) output. As the GSM mobile cell phonewith time division multiple access (TDMA) technology to different time periods (time slot) taken between user, system, time synchronization with mobile phones is very important. Such as mobile phones clock with the system clock is not synchronized, it will cause the cell phonecan not communicate with the system to normal. The longitudinal axis stands for the shielding radius of cell phone jammer.