The company exhibited some samples of cell phone jammer to the client

This structure is simple, but the stability is poor, only the early Nokia mobile phones (such as 8110,3810,6150,3210,7110, etc.) transmitter circuit adopted this structure. Direct conversion transmitter circuit. With the advent of new mobile phone, a number of new mobile cell phoneuse in direct conversion transmitter. Such as the Nokia 8210,8850,3310 phones. This receiver circuit shown in Figure 4-16. This transmitter circuit, logic circuit audio output TXI / Q signals directly to SHFVCO signal (local oscillator circuit of this structure is generally referred to SHFVCO) modulation, the final transmit signal. Adapter of cell phone jammer is a kind of key part for cell phone blocker.
The characteristic parameters of a signal with another signal of a change in the process or process is called modulation. Carrier modulation parameters with the situation by changing the number of different modulation can be divided into two categories: continuous modulation and pulse modulation. Continuous modulation is divided into three types: amplitude modulation (AM): the amplitude of the carrier wave with the amplitude of the signal changes; frequency modulation (FM): the frequency of the carrier wave with the amplitude of the signal changes; phase modulation (PM): carrier phase with the signal wave amplitude changes. digital cell phoneuses digital modulation techniques. Digital mobile cell phoneis known as digital cell phoneis that it uses a digital modulation technique. In either transmitter circuit, TXI / Q signal output from the logic of the audio circuit, the RF circuit are to TXI / Q modulator. cell phone jammer plays an important role in protecting people’s privacy and security.
In the TXI / Q modulator, 67.707kHz of TXI / Q signal to modulate the transmitted carrier frequency, intermediate frequency signal has been already transferred. TXI / Q modulator is usually an intermediate frequency processing module, a small number of transmitters have a special modulator module. TXI / Q modulated carrier signal used in a frequency from the VCO circuit. For most phones, the receiver transmitter IF VCO and IF VCO shared, individual, there was a cell phonecall a special launch intermediate frequency VCO, such as the Motorola 928 cell phone. TXI / Q modulation diagram shown in Figure 4-17. Be noted that: Nokia 3310,8210,8850 and other mobile modulation circuit is rather special, the modulated signal is ultimately transmitted signal (via balanced / unbalanced converter directly added to the amplifier), rather than transmitting the modulated IF signal . cell phone jammer can use jammer’s omnidirectional antenna which can changed into directional antenna if reducing interference with outside environment is needed.
TXI / Q modulated signal processing circuit transmitting frequency, transmitter frequency circuit different phones are different, but mainly in two ways, the launch frequency circuit, TXVCO output signal all the way to the power amplifier circuit, the other way TXVCO signal mixing with RXVCO signal, reference frequency signal to be fired; launch with the launch of the IF signal has been adjusted reference IF signal conversion module during launch phase detector for comparison, and then by a pump circuit (a double-ended input, single-ended output of the converter circuit), the output pulse of a send data containing a DC control voltage signal. To control TXVCO circuit, forming a closed loop, so that the final output of the circuit by the TXVCO transmit signal is very stable. The company exhibited some samples of cell phone jammer to the client.
Block diagram shown in Figure 4-18. The vast majority of mobile cell phonetransmitter frequency circuits have adopted this approach. 2 on the transmitter on the frequency inverter circuit emission spectrum is actually a moving circuit for the transmitter with a transmit frequency on the circuit. Inverter on the launch, the launch processing circuit output IF transmit modulated IF signal, and RXVCO (or UHFVCO, RFVCO) signal mixing, the final transmit signal. Transmit up-converter is a mixer circuit. Talked about in the mixer, the mixer has two input signals, an output signal. Launch on the same frequency, it has been tone input signal is transmitting IF signal and UHFVCO (RXVCO, RFVCO), the output signal is finally transmitted signal. cell phone jammer is of small volume and light weight.