Radio remote control is used in many fields due to its advantages of long transmission distance, strong anti-interference ability and no directionality. However, due to complex electrical appliances, huge sending equipment, and difficulty in debugging, etc., it has been restricted in the civilian field. With the development of electronic technology, these problems have been solved, making it have a strong vitality.
Here I will introduce a method of making a radio-controlled transmitter and receiver.
Circuit introduction The radio remote control transmitter is a miniature transmitter with a transmission frequency of 315MHz and a 12V power supply. The remote control distance is 100M and the operating current is only 4mA. The radio receiver is a receiver and demodulator like the high-frequency head of a TV. Its typical working voltage is 6V, the waiting current is 2mA, and the receiving frequency is 315MHz. Using them, various radio remote control devices can be easily manufactured, which have the advantages of miniaturization, long transmission distance, low power consumption, and strong anti-interference ability. Can easily replace infrared, ultrasonic transmission and receiving head.
The principle of the radio head circuit is shown in the figure. Circuit four transmitting tube V1 and peripheral components C1, C2, L1, L2, etc. constitute an ultra-high frequency transmitting circuit with a frequency of 315MHz, and transmit to the air through loop antenna L2. Antenna L2 uses silver-plated wire or enameled wire with a diameter of 1.5mm, and the antenna size is 24mm (length) X9mm (height). Transistor V1 selects high-frequency transmitter BE414 or 2SC3355.
The circuit principle of the radio remote control receiver T631 is shown in the figure. The receiving circuit is mainly composed of V1, IC, etc. V1 and C7, C9, L2 and other components constitute an ultra-high frequency receiving circuit, fine-tuning C9 to change its receiving frequency, so that it is strictly aligned with the 265MHz transmitting frequency. When the antenna L2 receives the modulated wave, it is tuned by V1 to amplify the low-frequency component, and then pre-amplified by V2 and sent to IC LM358. After further amplification and shaping, it is output by pin 7 of LM358. The actual size of the printed circuit board is 31mmX23CC The size is 27mm (length) X9mm (height). OUT is the signal output terminal, the transistor V1 selects BE415 or 2SC3355. Capacitor C9 can choose small adjustable capacitor. IC selects LM358.
In order to reduce the volume in the transmitting and receiving circuits, all the resistors use 1 / 8W or 1 / 16W metal film resistors; electrolytic capacitors also use ultra-small capacitors, and other capacitors all use high-frequency ceramic capacitors. When soldering, the component pins should be as short as possible to make them close to the circuit board. The circuit board material should be a high-frequency circuit board.
The following is a two-transceiver device that uses an acoustic surface. Compared with the previously introduced circuit, it has a longer transmission distance, stronger anti-interference ability, and easier production and debugging. The price is
Launch part:
Receiving part:
Follow WeChat
Download Audiophile APP
Follow the audiophile class
related suggestion
wireless microphone,