2. Find the correct variant.

1. How many separate transmitters are employed in the television system?

a) three

b) two

2 The optical image is converted into electrical impulses by…

a) the television camera

b) the television display

3. The aerial radiates the video signal into

a) dynamic

b) space

4. The sound and the image transmit

a) simultaneously

b) differently

5. The picture carrier is

a) frequency-modulated

b) amplitude-modulated

3. Make up sentences, using words and word-combinations.

Television transmitter, synchronizing, picked up, the camera, simultaneously, a single antenna, receiver, picture carrier, are converted, correspond.

Additional material for card № 20

1. Read the text, translate it and answer the questions.

Television system

The television system is considerably more complex than the sound-broadcasting system. In a typical television system two separate transmitters are employed one for the sound channel and the other for the picture channel. The sound transmitter is frequency-modulated and simultaneously transmits the sound which accompanies the image. Each transmitter has its own antenna.

The image being televised is received by the television camera, which converts the optical image into electrical impulses. These electrical impulses are amplified by the video or picture amplifier. After proper amplification, the video signal modulates the high-frequency carrier of the television transmitter and is radiated into space by the aerial. The picture carrier is amplitude-modulated.

1. Which system is more complex-the television or the sound-broadcasting system ?

2 What transmitters are employed in a television system?

3. By what device are electrical impulses amplified?

2. Find the correct variant.

1. How many separate transmitters are employed in the television system?

a) three

b) two

2 The optical image is converted into electrical impulses by…

a) the television camera

b) the television display

3. The aerial radiates the video signal into

a) dynamic

b) space

4. The sound and the image transmit

a) simultaneously

b) differently

5. The picture carrier is

a) frequency-modulated

b) amplitude-modulated

3. Make up sentences, using words and word-combinations.

The cathode-ray tube, are reproducing, consist, a source of electrons, are formed, a deflection system, a screen, the electron beam, simultaneously, intensity.

Additional material for card № 21

1. Read the text, translate it and answer the questions

Television system

Special signals are sent out by the television transmitter in addition to the picture impulses. These special signals have the purpose of synchronizing the picture at the receiver with that being picked up the camera.

At the television receiver, the picture and audio signals are picked up simultaneously by a single antenna. The voltages induced in the receiving antenna are fed into the radio frequency stage of the receiver, and the picture carrier and the sound carrier are converted by syperheterodyne conversion method into two separate intermediate frequency signals. One signal corresponds to the sound carrier and the other- to the video or picture carrier. Two separate intermediate frequency amplifier channels are employed, one for the picture signal and other for the sound signal.

1. By what means are the pictures at the receiver synchronized with the picture of the camera?

2 By what method are the picture carrier and the sound carrier converted into separate intermediate frequency signals?

3. What way are the picture and audio signals picked up?