B. Text Study. I. Look at the title of the text

I. Look at the title of the text. Make your predictions about the content of it. Read the text and answer the questions.

1. What is radio communication?

2. What are the main components of radio?

3. What is the difference between radio waves and other waveforms?

Text B

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 more amplifiers. In modern transmission electron tubes are used to amplify currents and give greater transmitting range and better reception.

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

Electric oscillations are produced in the antenna of the transmitter. They travel in all directions.

Radio waves are electric waves of very high frequency; they travel through space at the speed of light. They differ from other waveforms only in frequency (number of vibrations per second).

II. Read the text and define whether the following statements are true or false.

1. Radio communication means the transfer of high-frequency energy along the wires.

2. The main components of radio are a transmitter and a receiver.

3. The transmitter consists only of some amplifiers.

4. Radio waves are low-frequency electric waves.

5. Radio waves differ from other waveforms in wavelength.

III. Expand the sentences.

1. Radio communication is a communication without wires.

2. Radio is a device for transmitting and receiving signals and programs by electromagnetic waves.

3. A transmitter and a receiver are the main elements of radio.

4. Radio waves are electric waves of very high frequency.

IV Now decide which of the following statements express important ideas or supporting details for this reading.

1. a) Radio is a device that transmits and receives signals by electromagnetic waves.

b) The process of radio communication includes transmission and reception of signals.

c) The necessary components of radio are a transmitter and a receiver.

2. a) The receiver is a device that receives waves sent out by a transmitter.

b) Radio receiver demodulates the waves.

c) Demodulated waves are heard as speech, music and signals.

3. a) Radio waves are electric waves of high frequency.

b) The travelling speed of radio waves through space is equal to the speed of light.

c) Radio waves differ from other waveforms in frequency.

V. Find the words – carriers of the primary and the secondary information in paragraph 3.

VI. Define the function of commas in the text.

VII. Find out the means of connection between clauses, parts of the sentence and sentences.

VIII. Arrange the sentences in the logical order according to the text.

1. In up-to-date transmission electron tubes are utilized to amplify currents.

2. Radio waves travel through space at the speed of light.

3. The main parts of the transmitter include a high-frequency oscillator and one or more amplifiers.

4. Radio communication is the transfer of high-frequency energy without wires.

5. The waves are demodulated by radio receiver and heard as speech, music and signals.

IX. Give the main points of the text in 4-5 sentences.

Поиск по сайту: