III. Match the words and translations

1. application	звуковая частота
2. audio-frequency	радиопередающие и радиоприемные устройства
3. amplifier	радиотехника
4. achievement	приемник
5. radio-engineering	применение
6. radio transmitting and radio receiving devices	использовать электромагнитные волны
7. to employ electromagnetic waves	высокочастотный генератор
8. receiver	передатчик
9. transmitter	достижение
10. high-frequency oscillator	усилитель
11. transmitting station	приемная станция
12. receiving station	передающая станция

IV. Fill in the gaps, choose the right words

1. Radio occupies one of the leading places among the greatest achievements of modern...

a) currents;

b) receiver;

c) engineering.

 

2. The energy is radiated into space from the... by the antenna.

a) receiver;

b) transmitter;

c) amplifier.

 

3. To... means to make bigger or enlarge.

a) amplify;

b) transmit;

c) radiate.

 

4. A transmitting antenna... radio waves.

a) receives;

b) reaches;

c) radiates.

 

5. Our scientists have great...in the field of radio and television.

a) achievements;

b) currents;

c) oscillations.

 

6. Radio finds a wide... in many spheres of our life.

a) application;

b) achievement;

c) transmission.

 

7. Any radio receiver has five fundamental

a) transmitters;

b)components;

c) oscillators.

 

8. Broadcast stations often use two or more

 a) currents;

b) antennas;

c) electrons.

 

 

Unit 5. Radio receiver

Active Vocabulary

to receive	принимать, получать
to mix	смешивать
to reject	отвергать, отказывать
to remain	оставаться
to select	выбирать, избирать
to tune	настраивать, наладить
fidelity	точность воспроизведения
sensitivity	чувствительность
intermediate	промежуточный
nearby	близкий, соседний
mixing valve	смесительная лампа
tuned aerial	настроенная антенна
intermediate frequency	промежуточная частота
rejector	отражатель
high fidelity	высокая точность
low sensitivity	низкая чувствительность
condenser capacity	емкость конденсатора
sensitivity control	регулировка чувствительности
near-earth space	околоземное пространство

I. Read and translate the text

Radio receivers

Most modern radio receivers are of super heterodyne type. In them, an oscillator generates a radio-frequency wave that is mixed with the incoming signal. As a result, a radio-frequency wave of lower frequency (called intermediate frequency) is being produced. In order to tune the receiver to different frequencies, the frequency of oscillations changes but the intermediate frequency always remains the same.

А good radio receiver should have high selectivity, high sensitivity and fidelity and low noise. Selectivity is achieved by a receiver receiving signals from one station and rejecting them from another station operating on a nearby frequency. A high-fidelity receiver contains both the tuner and amplifier circuits of a radio. And the high-fidelity radio may consist of a separate audio-amplifier and a separate radio tuner.

In radio communications, a radio receiver (receiver or simply radio) is an electronic device that receives radio waves and converts the information carried by them to a usable form. It is used with an antenna. The antenna intercepts radio waves (electromagnetic waves) and converts them to tiny alternating currents which are applied to the receiver, and the receiver extracts the desired information. The receiver uses electronic filters to separate the desired radio frequency signal from all the other signals picked up by the antenna, an electronic amplifier to increase the power of the signal for further processing, and finally recovers the desired information through demodulation.

The information produced by the receiver may be in the form of sound, images, or data. A radio receiver may be a separate piece of electronic equipment, or an electronic circuit within another device. Radio receivers are very widely used in modern technology, as components of communications, broadcasting, remote control, and wireless networking systems. In consumer electronics, the terms radio and radio receiver are often used specifically for receivers designed to reproduce sound transmitted by radio broadcasting stations, historically the first mass-market commercial radio application.

 

Radio

Radio is the technology of wireless data transmission over distances. As a rule, we think of radio in the context of FM or AM stations that broadcast news or music programmers, but in fact, radio waves are also used for sending and receiving data in such systems as Wi-Fi networks, communication satellites and Bluetooth devices.

 Work in groups and discuss the purpose of radio, the devices it involves, the principles its operation is based on. Try to give a definition of radio.