工业控制 | 能源技术 | 汽车电子 | 通信网络 | 安防监控 | 智能电网 | 移动手持 | 无线技术 | 家用电器 | 数字广播 | 消费电子 | 应用软件 | 其他方案

电路设计->信号产生电路图->其他信号产生器电路图->三级9V调频话筒(英文)-----Three Stage 9V FM Transmitter circuit

三级9V调频话筒(英文)-----Three Stage 9V FM Transmitter circuit

作者:dolphin时间:2012-11-22

Three Stage 9V FM Transmitter circuit diagram
This circuit is a powerful three stage, 9V FM transmitter (Tx) with a range of up to 1 kilometer in the open. It uses an RF transistor in its output stage and two BC547’s for the first two stages. Distance of trans-mission is critically dependent on the operating Conditions (in a building or out on the open), type of aerial used (single wire or dipole), operating voltage (12V is better than 6V) and if the circuit is peaked for maximum performance.
Three Stage 9V FM Transmitter circuit
Components List:
Resistors, 5%, 1/4W:
100R 1
470R 1
4K7 1
22K 1
39K 1
47K 2
1M 1
Capacitors:
Trim cap 5-20pF, red C 1
5.6 pF ceramic C 1
10p ceramic C 2
47pF ceramic C 3
1nF ceramic C 1
20nF or 22nF ceramic C 2
100nF monoblock C 2
RF transistor ZTX320 C 1
Small signal transistor BC547 C 2
6 turn tinned copper coil C 1
6 turn enamelled coil C 1
8 turn enamelled coil C 1
9V battery snap C 1
Electret microphone C 1
PCB-mounted SPDT switch C 1
Antenna wire 1.6m
The circuit is basically a radio frequency (RF) oscillator that operates around 100 MHz. Audio picked up and amplified by the electret microphone is fed into the audio amplifier stage built around the first transistor. Output from the collector is fed into the base of the second transistor where it modulates the resonant frequency of the tank circuit (L1 coil and the red trimcap) by varying the junction capacitance of the transistor. Junction capacitance is a function of the potential difference applied to the base of the transistor T2. The tank circuit is connected in a Hartley oscillator circuit. The final stage built around T3 amplifies the output RF signal.
Note:
This circuit comes from kitsrus.com and the kit for this circuit is available there.

关键词: 三级9V调频话筒

评论

技术专区