Power Engineering. Соколова Е.В. - 17 стр.

от условий на поверхности эмиттера. Этот эмиттер должен быть в хорошем ва-
кууме. Мы знаем, что вакуумные лампы широко используются в технике.

      6 Lesson 6

      6.1 Прочтите слова согласно транскрипции

      cathode, filamentary, alternating, determine , winding, channel, ceramic, ad-
vantage, uniform, refer, unimpotential, close , otherwise, affect, contribute.

      6.2 Прочтите слова, обращая внимание на смещение ударения

      filament -filamentary; determine - determination; possible - possibility; metal -
metallic; advantage -advantageous; contribute -contribution; magnet – magnetic

      6.3 Сгруппируйте эквиваленты

     to reduce fluctuation, result(in), close, advantage, to cause fluctuations, affect,
hum, winding, alternating(current), direct(current)

     переменный ток, вызывать флуктуации, постоянный ток, приводить(к),
преимущество, сокращать флуктуации, близкий, воздействовать(на), помехи,
обмотка

      6.4 Сгруппируйте антонимы

       heat , directly , frequently , increase , use , raise , internal , harm , cool , indi-
rectly , seldom , decrease , lower , external

      6.5 Прочтите и переведите текст

      Physical construction of cathode
       1. Two types of cathodes are employed in vacuum tubes ,the filamentary and
the indirectly heated. The filamentary cathode consists of a wire filament, usually
bent in the form of a V or a W, and is heated by the passage of a current; either direct
or alternating, through it. If alternating current is used for heating, as is most fre-
quently the case today the different parts of the cathode are not at constant potential,
on account of the IR drop of this current. Since the electron stream is determined by
the potentials of the other tube elements with respect to the cathode, this may cause
fluctuations which result in the development of hum in the tube output. To reduce
these fluctuations as much as possible, it is common practice to connect the return
circuit from the other tube elements to a center tap on the transformer winding which
supplies filament-heating current. This point is always at the average potential of the
entire filament.
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