Рубрика:
23
Semiconductors
A semiconductor is often defined as an electrical conductor that has a
conductivity intermediate between that of an insulator and that of a metal.
Some of the properties, which we now associate with semiconductors, have
been known for a century or more. Little use was made of these properties,
however, until the first decade of the last century, when practical semiconductor
detectors were developed for radio reception.
Engineers and scientists turned their attention to semiconductors more than
40 years ago. They saw in them a means of solving an old engineering problem,
namely, that of direct conversion of heat into electricity without boilers or
machines.
The most important among the semiconductor devices, the transistors,
were invented in 1948. Their invention and development resulted in the expanded
use of semiconductor devices of all kinds. Semiconductor devices can usually
perform all the elementary functions of oscillation, amplification, modulation
and demodulation, rectification, etc. with greater economy of cost, space, and
power, than can other devices such as vacuum tubes and relays. Semiconductor
devices are used in measuring techniques, automatics, computers, radio and
TV sets. A new industry – helioengineering
1
– has appeared. Solar batteries
are successfully operating on sputniks and spaceships.
NOTES:
1
helioengineering – гелиотехника
Контрольное задание № 2
RADIO ENGINEERING
Для правильного выполнения задания № 2 необходимо усвоить следу-
ющие разделы грамматики английского языка по любым учебникам:
1. Видовременные формы глагола:
А) активный залог (The Active Voice) для форм Continuous (Present, Past,
Future) и Perfect (Present, Past, Future);
Б) пассивный залог (the Passive Voice) для формы Indefinite (Present,
Past, Future);
Особенности перевода на русский язык пассивного залога английских
глаголов, имеющих предложное дополнение или дополнение без предлога.
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