5. Translate the words paying attention to the prefixes pre-, super-, in-, dis-:

prerevolutionary, prehistoric, pre-establish, prefabricated, predetermined, pre-set, precast, preheat, pre-sonic, superprecise, superconductor, superconductivity, super-high, inexhaustible, impossible, irregular, disadvantage, disconnect.

6. Translate the sentences using either … or, both ... and, as well as:

1. Напівпровідники використовуються як у фізиці, так і в техніці.

2. Метали та діелектрики є або дуже добрими, або дуже поганими провідниками електрики.

3. Сульфід кадмію, як і інші транзистори, діють у темряві як ізолятори.

7. Translate the sentences paying attention to the meanings of “provided”:

1. These experiments provided data necessary for the completion of our research. 2. All the members of the expedition are provided with all the necessary things. 3. Provided our plant is equipped with up-to-date machinery, we’ll be able to raise the quality of the manufactured goods.

8. Make up questions to the words in bold type:

1. Small dimensioned electronic devices consume very little power. 2. Under ordinary room lighting the resistance of transistors decreases millions of times. 3. Transistors revolutionized radioelectronics and electronics.

9. Fill in the blanks with the words given below:

Transformation, energy, properties, supply, insulators, sensitive, occupy, efficiency.

1. Semiconductors … an intermediate place between metals and insulators.

2. The transistors are successfully used for direct … of heat energy into electrical power.

3. Transistors are extremely … to external influences.

4. Cadmium sulphide as well as a number of other transistors, act as … in darkness.

5. The photoelectric … of transistors are largely used in TV sets, and other devices.

6. In this case electricity is directly transformed into light energy with great … .

7. The … of transistors is inexhaustible.

8. The … of light is transformed directly into electricity in photocells.

10. Finish the sentences:

    1. Semiconductors occupy …

    2. The transistors are successfully used for …

    3. Transistors are extremely …

    4. Cadmium sulphide as well as …

    5. The photoelectric properties of transistors …

    6. The turning of the tiny crystal into a transistor device …

    7. A very fine technology has been developed for …

Text 10 b Transistors and Semiconductor Devices

Study the text. Try to understand all details. Use a dictionary if necessary:

1. Devices consisting of solid pieces of crystalline material which allowed alternating current to flow more readily in one direction than the other were known long before the invention of the thermionic valve. The crystal set which became so well known in the early days of radio depended on the rectifying action at the point of contact between the surface of certain crystals and a fine wire. Crystal valves, using silicon crystals, were found to be more efficient for the very high frequency signals reaching radar receivers than any thermionic valves. The action of these devices was not understood, but they were all made from materials which we now classify as semiconductors: substances which let electric current pass through them more easily than insulators do but much less easily than do true conductors.

2. In 1948 Bardeen and Brattain invented the point-contact transistor and Shockley invented the junction transistor shortly after. The transistor is a semiconductor triode possessing characteristics which are similar in many respects to those of thermionic triodes. At present transistors are widely used in amplifiers, receivers, transmitters, oscillators, TV sets, measuring instruments, pulse circuits, computers, and many other types of radio equipment.

3. The invention of transistors and solid-state devices led to an acceleration in the growth of electronics. Why were these new devices so important and why are they steadily replacing their older equivalents? A brief review of their advantages compared with thermionic devices will provide the answers to these questions. Transistors are made from parts which do not wear out. Transistors waste very little power. They require no heating to generate their free electrons. This means that equipment made with transistors is more efficient, lighter than comparable valve equipment.

4. Since no heating is required there is no delay in transistor equipment waiting for things to warm up, as there is with thermionic valves. This is a great advantage with ‘entertainment’ equipment, such as radio and television receivers, and it may be vital with some kinds of measuring or recording equipment.

5. Their very small size and weight, combined with low heat dissipation, permits very high density packing of components and, in combination with their reliability, this has made possible the design of the very compact circuits which are essential for such applications as computers, portable measuring instruments, satellite instrumentation, etc.

Notes

1. crystal set – детекторний приймач

2. crystal valve – кристалічний прилад

3. heat dissipation – розсіювання тепла

Unit 11

Grammar:

Participle (Passive and Perfect Forms)

TEXT 11 A

RADIO AND TELEVISION

The radio is probably the only invention, which has found universal recognition and application in a comparatively short time.

Radio supplies the communication service, which is so essential to the modern world, and meeting these needs it has become a rapidly developing industry itself. It is from radio that the subject of electronics was born which being applied to automation brought such remarkable changes to the technique of to-day.

The fastest, most reliable way to detect an artificial satellite and to determine its orbit is by radio. It is by means of radio that we receive most of the information collected by the satellites at the borders of space. Without radio we should be hardly able to observe them at all. Indeed, radio makes it possible to follow them even when they are too small to be visible.

More obvious still is the ever-growing influence on mankind of radiobroadcasting, both sound and television. Along with the construction of television centers powerful relay-stations located at considerable distances from the main television centers are being built. Extensive work is also being carried on in the field of colour television.

Having already made remarkable progress, radio and television continue to develop and to find wider and wider application in science, industry and agriculture. They enable us to measure distances on land and water, to see through the surface. Specially designed radio and television sets can be found on board a ship, on board a plane, on the very bottom of the sea.

Radio and television are not only the reliable means of communication but also effective means of educating people, spreading knowledge and ideas and raising the cultural level of the population.

In radioastronomy radiotelescops are used to investigate the Universe, to obtain data on chemical composition and surface conditions of the Sun and other planets.

Radio engineering technique is widely used in radiotelemetry to indicate or record a measurable quantity at a dis­tance.

At present we produce equipment for powerful broadcasting and television centres and radio-relay stations, electronic computers, radar stations, telecontrol and telemetric sys­tems, etc.

Radiobroadcasting is the technique of use of radio (elec­tromagnetic) waves for wireless transmitting of sound.

Radiowaves are produced at the broadcasting station and radiated by the aerial. Radiowaves generated by the radio transmitter and emitted by the aerial propagate in all di­rections. Radioreceivers receive, transform and amplify the energy of radiowaves into audio signals so that they can reach the loudspeaker, headphones, a relay, recording equip­ment, etc. Radioreceiver is one of the main elements of broadcasting, communication systems, television, radar and many other fields of engineering. The lower the power of signals received, the higher sensitivity of the receiver should be.

Broadcasting based on digital coding has revealed many advantages over conventional broadcasting. It consists in converting soundwaves into series of digits and their subsequent transmission in the form of monofrequential pulses. A signal is then received and after amplification is sent to the acoustic system for reproduction. Digital coding enhances the quality of broadcasting, makes it possible to reduce considerably the size of new receiver – decoders. In digital broadcasting more than one station can use one and the same wavelength without interference.

These few examples give but a poor idea of what other uses radio and television might still find in various spheres of life and how much they would contribute to the further progress of science.

Answer the questions:

1. What invention has found universal recognition and application in a comparatively short time?

2. What are the advantages of radio?

3. What can you say about the influence of radio and television on mankind?

4. Where do radio and television find wider and wider application?

5. What are the advantages of broadcasting based on digital coding?