Telecommunications: a brief historical review

1. The first true telecommunications system using electrical signals to carry messages started in the 1840s with machine telegraphy. Samuel Morse first developed *11.9 the telegraph in 1832 but it was not until the mid-1840s that* 4.1.1 the system was put into practical use* 10.1 –sending coded electrical messages (Morse Code) along the wires. The telegraph became a rapid success, its speed quickly outdating the Pony Express (=обычная почта) for long-distance communications. *8.4

2. The next major step forward came in 1878 with the invention of the telephone by Bell. This enabled speech to be transported *8.1 as electrical signals along wires and revolutionized personal communications.

 

3. In 1886, Hertz verified experimentally that electrical energy could* 5.6.1 be radiated and thus proved the existence of electromagnetic waves. This opened the way for the free-space transmission of information without wires. This provided the basis for all radio and TV broadcasting.

4. In 1897, Popov successfully carried out his experiments at sea, having succeeded *7.3.2.2 in effecting radio communication between the shore and the sea at a distance of 3 km.

5. In 1901, Marconi established long-distance telegraph communication by transmitting between England and Canada. Although he did not realize it at the time, he achieved such long distances by reflecting radio waves in the ionosphere (layers of ionized gases and electrons existing in the Earth` upper atmosphere at heights of 50–500 km). This overcame the problem of transmitting round the Earth from one side of the Atlantic to the other.

6. With the discoveries of the diode and thermionic valve in the early part of this century, advances were made in both receiver and* 9.1.2 transmitter design* 11.8 with an associated impact in telegraphy, telephony, and civil and military communications. Radio broadcasting soon followed, with powerful transmitters serving to communicate over wide areas. Television (TV) was first established in 1937. Radar (radio detection and ranging) was also developed from the 1930s and played a vital role in aircraft detection and navigation in World War II.

7. As further* 3.2 advances in technology took place* 10.1 (e. g. the invention of the transistor in 1947 and the subsequent development of microelectronic integrated circuits technology), new applications became feasible, and new systems were developed.

X. Письменно озаглавьте 6 и 7-й абзацы текста.

Вариант 2

I. Перепишите предложения и переведите их, принимая во внимание различные функции слов it, that (those), one (см. грамм. справ.: 4.1, 4.4, 4.3, а также ссылки после *).

1. It is clear that these diagrams are alike.

2. It is the movement of electrons which constitutes an electric current.

3. Conditions on board a space vehicle *2.2 differ drastically from those on the surface of the Earth.

4. One must know that a high-frequency current radiates electromagnetic energy.

II. Перепишите предложения и переведите их, учитывая особенности перевода на русский язык определительных блоков существительного с левым или правым определениями (см. грамм. справ.: 2.2, 2.3, 2.3.1, а также ссылки после *).

1. The modern interest in light wave communication dates from the first demonstration of laser in 1960.

2. Reactive gas plasma technology is in wide-spread use in the semiconductor industry.

3. With microprocessor chips available, we can afford more control* 11.8. of the events in an internal cycle.

III. Перепишите предложения, определите в каждом из них глагол-сказуемое, его видовременную форму и залог. Переведите предложения на русский язык (см. грамм. справ.: 5, 5.1, 5.2, 5.3, 5.4, 5.5, 5.5.1, 5.5.6, 11.13, а также ссылки после *).

1. This arrangement gave an electrical signal that did not *4.2.1 requireamplification.

2. Radio has become *5.4.1 a powerful means *11.2 of progress.

3. The discovery of the double nature of electrons was followed by a change in the quantum theory.

IV. Перепишите предложения, подчеркните в каждом из них модальный глагол или его эквивалент. Переведите предложения на русский язык (см. грамм. справ.: 5.6, 5.6.1, 5.6.3.2, а также ссылки после *).

1. Several factors should be considered *11.9 when we analyze the experimental results.

2. A telephone network can be used to connect personal computers to an electronic e-mail system.

3. In all cases, the received signal must be converted by a transducer such as a loudspeaker.

4. Computers cannot be called «brains». *11.17

V. Перепишите и переведите предложения, учитывая различные функции глагола to be (см. грамм. справ.: 6, 6.1, 6.2, 5.6.3, 5.6.3.1, 5.5.1, а также ссылки после *).

1. There was a problem of negative feedback.

2. The problem is to choose a suitable filter.

3. The fixed coils of a wattmeter are to be connected in series with the load.

4. These devices are being used more *3.2 extensively.

VI. Перепишите и переведите предложения, учитывая различные функции глагола to have (см. грамм. справ.: 6, 6.1, 6.3, 5.6.3, 5.6.3.1, 5.5.1, а также ссылки после *).

1. It is a well-known fact that cordless *1.1 telephones have a limited mobility.

2. A computer displays results after *9.2(1) it has performed calculations.

3. All the input pulses have to be of identical form.

4. Virtual reality techniques have been used to make a 3D model (=трехмерная модель) of the planet Mars.

VII. Перепишите и переведите предложения, обращая внимание на перевод парных союзов и многозначность некоторых служебных слов (см. грамм. справ.: 3.5, 9.1.2, 9.2 (1,2), 11.6, 11.7, а также ссылки после *).

1. Filaments may be heated either by DC or AC, but in the latter* 4.5 case hum may by created.

2. Since there is* 6.2 (6) no electrostatic field near the cathode, the plate current through the tube is zero.

3. Once generators are operating in parallel, they are in synchronism.

VIII. Перепишите и переведите предложения, обращая внимание на перевод устойчивых словосочетаний (см. грамм. справ.: 10, 10.1, 10.2, 10.3, 11.12, а также ссылки после *).

1. This auxiliary winding, due to its size, position, and other arrangements, produces a revolving* 7.3.2.1 field.

2. Most of *3.1 the tools that we have invented have helped our bodies rather than our minds.

IX. Прочтите и устно переведите текст, затем письменно переведите 3, 4 и 5-й абзацы текста.