Monochrome TV transmitter

   Have you ever thought about transmitting audio and video signals? There is a simple monochrome TV transmission that amplifies and transmits audio, video signals. These are transmitted in very high frequency bands (VHFs).

MONOCHROME T.V TRANSMITTER

Its important parts are as follows.

1. T.v camera- T.V  The camera is a device that converts optical images into electrical signals.  Hence TV  The amplitude of the signal received from the camera changes according to the light intensity of the scene 
2. Video amplifier- The main function of a video amplifier is to increase the boltage level of the composite video signal, so that the voltage label of the composite video signal can be increased to the transmittable level.  The output of this section is a fully prepared composite video signal for transmission.
3. Camera amplifier- TV  The electrical signal received at the output of the camera is very weak, which needs to be amplified.  Hence TV  Camera Amplifier Functions  The electrical signal from the camera is to be amplified
4. Deflection and A. P. Generation- The main function of this unit is to provide oscillators to provide horizontal and vertical deflection in the camera tuve, and synchronization and Blaking Plus are also provided by this unit.  Hence it provides system scanning as well as system synchronization.
5. Audio amplifier- Audio amplifier is used to increase the voltage label of the audio signal, and a loud speaker is also used to check the audio signal at this stage.
6. M.F Modulator-  F. M .  The major function of the modulator is to modulate the frequency of the output signal received from the pre-emphasis circuit (pre-emphasis ckt).
7. Power amplifier- Modulated R. F .  The power of the modulated signal received from the amplifier is not sufficient for transmission.  Therefore, the signal received from this stage is fed into the power amplifier.  So that the power level of the signal can be increased.
8. R.F amplifier- The signal coming in this stage is negatively coupled to the carrier signal R. M . Modulatids do.  Crystal oscillator of carrier signal, frequency multiplier and R.F . Is provided by the multiplier, and the function of this unit is also to increase the signal's video label.
9. scanning circuit- Its main function is TV.  The camera has to be scanned, and the received signal is called AM  Modulating amplifier has to be provided as input
10. Combining network - The use of this network is to combine signals coming from all the circuit networks and provide suitable output, which is transmitted by the transmitter antenna.

 

Scanning process

     The Horizontal Sweep Oscillator provides current to the Horizontal Deflection Coil when the camera is turned on, at the same time the Vertical Sweep Oscillator is also triggering, which provides the current to the vertical deflection coil. Due to which vertical and horizontal scanning starts simultaneously. And as the horizontal deflection coil deflects the electron beam to the right, at the same time the vertical deflection deflects the coil downwards. The current value is gradually increased on the Horizontal and Vertical Deflection Horoscope. And when the current value on the horizontal and vertical deflection coil reaches the maximum value. The electron beam then reaches downwards to the full right.

The current value on the horizontal and vertical deflection coil has to be reduced to the initial value to move the electron beam upward again. Since the horizontal and vertical deflection is applied to the saw tooth wave, it is characterized that the current value automatically returns to zero after reaching the maximum value, causing the electron beam to re-initialize. That is, the left returns to the bottom.

The process of scanning is just like reading a page of a book. Just like you start reading a line to read a book. Finish reading a line from left to right and this process continues until the entire page is over.