XIX. Choose one of the titles to best match the text.

.

• Electronic devices

• Pre-history of electronics

• Technological progress

XX. In the text you came across an electronic device called “radar”. What does the acronym “radar” mean? Choose from the following.

• radio defining functions and roads

• radio differential for accurate rolling

• radio direction-finding and ranging

XXI. a. Work in groups to explain how radar operates and fun-ctions.

b. Think of any other electronic devices of the same kind. Present your suggestions to the class.

XXII. Try to find more interesting information about any of electronic device and present it in your class.

XXIII. Read TEXT 5 C. Answer the questions that follow it.

TEXT 5 C. The Microelectronic Revolution

To understand just how much impact the invention of the transistor was to have, you have to remember that, before transistors came on the scene, every electronic machine required the use of valves (or in the USA, ‘tubes’). Valves are rather inconvenient for handling electronics. They are rather large, consisting of a glass envelope (like a fight bulb) containing dozens of tiny metal pans. And they are also extremely wasteful of power. On the other hand, hardly any power is wasted by transistors. They can easily be mass-produced and involve a minimum of mechanical parts, just the connecting wires, in most cases. The production process is photo-graphic and chemical, not an assembly of parts in the usual sense.

That brings us to a most important point: there is almost no limit to how small a transistor can be made. Using microelectronic techniques, you can easily make electronic circuits very complicated, well, and very cheap.

Just how much smaller and cheaper is hard to visualize. Try this. One of the first working, large-scale digital computers was made in the late 1940s.

It occupied an area approximately equal to that of a large hotel suite, and used as much power as a medium-sized street of houses. It was vastly expensive and vastly unreliable – on average; a valve had to be replaced once every ten minutes. ‘Pорu1аr Mechanics’ magazine, forecasting the rentless march of scientific progress in 1949, observed that “…computers in the future may weigh no more than 1.5 tons.” A pocket calculator that is substantially more powerful than any computer that was made before 1970, runs all year on batteries, and doesn’t weigh as much as 1.5 tons.

• How rapidly have new achievements in investing and developing of new electronic technologies been made?

• How microelectronic techniques contributed to the progress of science?

Lesson 6. Electronic devices: amplifiers, diodes, oscillators

TEXT 6 A. Amplifiers;

Grammar Exercises (Word Order in a Simple Sentence. Negative Simple Sentence. Word Order in Interrogative Sentences);

TEXT 6 B. Diodes;

TEXT 6 C. Requirements for Oscillators.

Pre-Text Exercises

Pre-Text Exercises

Active Vocabulary

I. Practise reading the words written below. You’ll come across them in text 6 a.

amplifier …………... pick-up cartridge ….. conventionally …….. pre-amplifier ……… power amplifier …… to drive ……………. circuit ……………... configuration ……… alternation voltage … to conduct …………. base-emitter ……….. junction …………… bias ………………... potential …………... substantially ………. output ……………... linear ……………… curve ……………… resistor ……………. collector …………... headroom …………. excursion ………….. gain ……………….. leakage current ……. ambient …………… feedback loop …….. input ………………. to reduce …………..

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