Small TV Transmitter Circuit

This compact video transmitter is highly effective for short-distance video surveillance, operating efficiently up to 100 meters. It can be paired with either a black-and-white or infrared camera module, providing excellent image quality on standard color or black-and-white televisions. Instead of using the BFY90 transistor, any VHF NPN transistor can be utilized, and any NPN transistor can replace the BC550. The concept involves creating a small television transmitter that accepts input from a digital set-top box. The digital video signal must be converted into an analog video signal for transmission, which can then be received in a local area using an aerial or antenna.

This video transmitter circuit is designed to facilitate short-range video surveillance applications, making it suitable for various environments such as homes, offices, or industrial settings. The core functionality relies on the conversion of digital video signals from a set-top box into analog signals that can be transmitted over the air.

The circuit typically consists of a camera module, which can be either black-and-white or infrared, depending on the surveillance requirements. The choice of camera impacts the quality of the transmitted video, with infrared options providing enhanced visibility in low-light conditions.

The transmitter utilizes a VHF NPN transistor, which serves as the main amplification component for the RF signal. This is crucial for ensuring that the transmitted signal can cover the required distance of up to 100 meters. The circuit should be designed to include appropriate biasing resistors and capacitors to stabilize the transistor operation and filter the output signal.

To convert the digital video signal into an analog format, a video encoder circuit may be incorporated. This encoder will take the digital input from the set-top box and process it to produce a composite video signal suitable for RF transmission. The output of the encoder is fed into the transmitter stage, where it is modulated onto a carrier frequency suitable for VHF transmission.

The overall design must also consider the antenna system, which is essential for effective transmission and reception. The antenna should be tuned to the operating frequency of the transmitter to maximize signal strength and minimize interference.

In summary, this video transmitter circuit is a versatile solution for short-range video surveillance, combining efficient signal processing with reliable transmission capabilities. The use of standard components allows for easy assembly and customization, making it a practical choice for various surveillance applications.This small video transmitter is very usefull for video surveillance on short distances ( up to 100m ) equipped with a black and white or infrared camera module it delivers excellent pictures on a standard color or b/w tv. Instead of BFY90 you can use any VHF NPN transistor and instead of BC550 any NPN transistor. suppose we make small tv transmitt er and give input from any digital set-up-box, then the digital video signal have to convert into analog video signal and transmit the analog signal to air, and we can watch with the help of an Ariel or an antenna in local area. 🔗 External reference