High quality of china cell phone jammer

Discrete low-noise amplifiers are usually in a common emitter circuit, to the weak RF signal amplification and offset caused by the RF filter insertion loss. In the low-noise RF transistor amplifier, low noise performance from the start, its bias or bias supply filter through the supply of electrical resistance, this can avoid power supply noise and bias resistor thermal noise introduced into the RF channel, the impact amplifier noise performance. Figure 4-7 Motorola P7689 phone GSM900 low-noise amplifier circuit. In the circuit, low-noise amplifier transistor Q400 is the core of the device. Q400 and the surrounding components together constitute the GSM900 low-noise amplifier. Which is the input capacitance C402, C405 is the collector output capacitance. LA02, R401, C403 and so together constitute a reactance filter power supply circuit, the RX-275-GSM power supply filtering, and then to the Q400's collector power. The inspection report of  cell phone jammmerneeds the signature of the director of  cell phone jammmerworkshop.
I_A01, R403, C403, also constitutes a reactance filter circuit, the RX-275-GSM power supply filtering to Q400's base power. R401 is the exchange of load resistance, Q400 amplification is demonstrated by the resistance to adopt. L402 is the DC collector channels. In the base circuit, resistor R403 form a fixed bias circuit. Q400 in the core of low-noise amplifier circuit and the first one after one, there is a RF filter. The two RF filters are band-pass filter, allowing only the RF band GSM reception signal. The factory inspection and acceptance personnel should sign the report of  cell phone jammmerif  cell phone jammmer is qualified. Ribbon–cutting Ceremony of  cell phone jammmer Factory
Shown in the figure is a circuit with a switch double hearing device components, TXVGSM and TXVDCS the control side, GSM-TX, GSM-RX not representative of the GSM transmitter and receiver ports, DCS-TX, DCS-RX represent 1800MHz transceiver's transmitter and receiver ports. Dual hearing device GSM and DCS RF signal RF signal separation, and the switching circuit will transmit and receive RF signals RF signal separation. Nokia 3310 cell phone with built-in antenna. Antenna receives induction of cellular high-frequency signal is converted into electrical signals, these signals include GSM900 receive RF signals. DCSl800 receive RF signals, and other unwanted signals. The factory plans to employ more workers to improve the productivity of  cell phone jammer.
Antenna to the RF signal is first to reach Z502. Z502 is a dual information contained RF switch devices. Its GSM and DCS RF signal RF signal channel switching, but also for receiving and transmitting RF signals to be separated. Z502 module control signal from the N500. When TXVGSM signal is active, Z502 GSM antenna connected to the receiver and transmitter circuit; when TXVDCS signal is active, Z502 connect the antenna to the DCS receiver and transmitter circuits. As can be seen from the above analysis, two information and antenna switch in the circuit structure and function are very similar, the difference is, the antenna switch IC is a set of internal switches and no filter, and dual-duplex information not only inside filter, but also includes the switching circuit. The factory has got more market share recently for the low price and high quality of  china cell phone jammer.
Low-noise amplifier in the antenna circuit is mainly sensitive to the weak RF signal amplification in order to meet the mixer input signal amplitude requirements. In the cell phone circuit diagram, the low noise amplifier is the abbreviation of LNA (Low Noise Amplifier). Receiver low-noise amplifier is the first stage amplifier circuit, the circuit is located after the antenna. Before and after the low noise amplifier, RF filters usually have. Low-noise amplifier is a high-frequency small-signal amplifier, the amplifier transistor requires a high cutoff frequency, magnification, noise coefficient. The first-level signal is very small, lower than the operating point is usually set at the same time plus current negative feedback, reducing the noise. High-frequency amplifier circuit using low-noise amplifier can improve the overall receiver noise figure. While high-frequency amplifier also prevent RXVCO signal radiated from the antenna path. The general manager promises that the bonus will be higher if the worker can complete the tense production task of  cell phone jammmer.