Radio Communication

Radio communication is the transfer of high-frequency energy from the transmitter to the receiver without wires.

Radio is a device that transmits and receives signals and programs by electromagnetic waves. Since the process of radio communication includes transmission and recep­tion of signals, the necessary components of radio are a transmitter and a receiver.

The transmitter is a device that produces radio-frequen­cy energy. The main parts of a transmitter are a high-fre­quency oscillator including an oscillatory circuit and one or a few amplifiers.

The receiver is a device that receives waves sent out by a transmitter. Radio receiver demodulates these waves and they are heard as speech, music, or signals.

Electric oscillations produced in the antenna of the transmitter travel in all directions. Radio waves are waves of very high frequency; they travel through space at the speed of light. They differ from other wave forms only in frequency (number of vibrations pat second).

Vocabulary:

transfer – передача

to differ (from) –отличаться

since – так как

necessary – нeобходимый

space – пространство

speed – скорость

amplifier – усилитель

Task 2. Translate the following word combinations:

high and low frequency energy; necessary amplifier parts; bad reception;

oscillatory circuits; changing wave direction; wave modulation

Task 3. Read and translate the following words without a dictionary:

amplitude, crystal, station, plan, operation, idea, cycle, variant

Task 4. Read and translate the following sentences:

1. The necessary components of a transmitter are a high-frequency oscillator, an amplifier, and electron tubes.

2. Electron tubes...

— amplify currents.

— give greater transmitting range.

— give better reception.

3. A receiver...

— receives high-frequency energy.

— demodulates high-frequency energy.

4. Radio waves...

— travel through space.

— differ from other wave forms.

— travel at high speed.

—travel in different directions.

Task 6. Look at this picture and give the answer what do you think about it?

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