еских заданий.
1) Орг. момент.
Good afternoon everybody. Im glad to see you. Lets start our lesson. Today we are going to work with text Push-pull Amplifier and to learn about the subjunctive mood, Conditionals type 2.
2) Работа с текстом Push-pull Amplifier.
So, lets read the text about push-pull amplifiers. Pay attention to the new words, please.
To feed - питать
To include - содержать, заключать в себе
To remain - оставаться
To push - толкать
To pull - тянуть
Push-pull - пушпульный
Push-pull amplifier - двухтактный усилитель
Push-pull circuit - двухтактная схема
Push-pull transformer - пушпульный трансформатор
Feedback - обратная связь
Feedback amplifier - регенеративный усилитель
Feedback coil - катушка обратной связи
Feeding transformer - силовой трансформатор
Now, read the text silently to guess the main idea.
Push-pull Amplifier.
An amplifier is used to produce the output voltage greater than the input voltage. A push-pull amplifier includes two tubes. Their control grids are connected to the opposite ends of the input transformer secondary winding. The centre of this winding is connected to the tube cathodes. When maximum grid voltage is produced in one tube, minimum grid voltage is produced in the other tube. Thus, the sum of the plate currents remains constant.
The plate currents are fed into the opposite ends of the output transformer or a choke coil. It has its centre connected through the plate current supply to the cathodes. Thus direct current plate components are eliminated but alternating current components add in the circuit.
Look through the text and complete these sentences, using the correct variant:
1) An amplifier is used a) to separat
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