In this note, we are going to know about Color TV Transmitter Block Diagram. Welcome to Poly Notes Hub, a leading destination for engineering notes for diploma and degree engineering students.
Author Name: Arun Paul.
Explain the Color TV Transmitter Block Diagram
Here is the block diagram of Color TV Transmitter with explanation –
Transmission and reception of a color picture are more complex than a monochrome picture because of the requirement of compatibility with black and white pictures. The basic features of a compatible color Transmitter are shown in Fig.
For color Transmission, colors from a picture are separated into three primary colors, red green, and blue with the help of prisms or dichroic mirrors and color filters. The brightness present in each color is converted by color camera tubes into three electrical signals.
The three color signals are passed through a resistive matrix to obtain the resultant luminance signal (called Y signal), using Grassman’s law (Y=0.59G+0.3R+0.11B). Color signals are sent in the form of color difference signals.
A color subcarrier (4.43 MHz in the European system and 3.58 MHz in the American system) is modulated by two weighted color difference signals (B-Y and R-Y), using synchronous quadrature modulation. This is called a color encoder. The color difference signals when multiplied by suitable factors to prevent overmodulation, are called weighted color difference signals. Its output is called chroma signal (or C signal).
Then luminance signal Y and chroma signal C are added and modulated to the main video carrier signal, using the AMVSB technique. This modulated RF carrier is transmitted along with an audio-modulated RF carrier through a common transmitting antenna with the help of a diplexer.