Radiotechnical Communication Components. Радиотехнические средства связи. Учебное пособие

Writing

HOW TO WRITE A SUMMARY

A summary is a brief statement or account of the main points of a piece of writing.

A summary is not a rewrite of the original text and does not have to be long. Your purpose in writing the summary is to give the basic ideas of the

original reading.

What was it about and what did the author want to communicate?

1. Identify the type of work (text, article), title, author, and main point.

In the text (article) “ …” the author presents (shows, describes...) his opinion on the hot topic of living in a technological society.

The text “ … ” deals with the problem of... (discusses some problems relating to..., provides information on...).

2. Write in the present tense.

At the beginning of the text / article the author characterizes... (comments on..., explains..., analyses...).

Attention is drawn to the fact that.... It should be noted that....

3. Don't forget to include linking words so your reader can easily follow your thoughts.

Next / Further / Then it is reported / shown that....

4. Don't copy the article. Instead, paraphrase.

Besides the author explains that..., gives a detailed analyses of... (the description of...). Finally the author comes to the conclusion that....

5. Don't put your own opinions, ideas, or interpretations into the summary.

Your summary should have between 100 and 120 words.

14. Write the summary of the text "The History of Radio".

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Lesson 2. Types of Rays

Preview

Before you read

1.How many kinds of rays do you know?

2.Are the rays visible?

Reading

1. Read the text

Types of Rays

There exist seven kinds of rays. We find them in different places, and use them in different ways, but they are close relatives. They are members of one family, the family of electromagnetic waves.

The kind of ray that mankind has known for the longest time is light. It helps us see the objects that surround us, when the objects reflect the light into our eyes. Because our eyes can detect light, we call it a visible ray. The other rays are invisible.

We find three types of invisible rays in use in our homes. When we listen to a radio program, we are using the rays that are called radio waves. When we cook a meal on an electric cooker, we are using infrared rays, sometimes referred to as heat rays. When we sit under a sun-tan lamp, we are using ultraviolet rays. We meet the other three types of rays outside the home. Inside the hospital we can find X-rays, produced by X-rays machines,

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and used for taking pictures of the insides of our bodies. At airports everywhere we find microwaves used with radar equipment to detect planes in the air, or guide them in to land. Also in hospitals we find gamma rays used as invisible bullets to kill cancer cells.

These seven types of rays resemble each other in that they are all electromagnetic waves. What makes them different from each other is their frequency or their wavelength. The distance that the wave moves during the time it takes for one complete cycle of vibration is called the wavelength of the wave. The frequency is the number of cycles in a second. Notice that radio waves are the longest of the electromagnetic waves and have the lowest frequency.

Developing academic vocabulary After-reading tasks

2. Make the glossary and translate the words into Russian

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19distance

20antenna

21problem

22element

23progress

24result

25test

3.Translate the sentences with the words from the glossary

1.We used different methods of calculation, but we both got the same

result.

2.Tungsten carbide tools are used extensively for machining steel.

3.The object of their expedition was to discover the source of the River

Nile.

4.Aircraft manufacturers want to reduce vibration for the sake of safety.

5.The vibration can become irksome after a while.

6.We know that prolonged exposure to vibration can weaken aircraft components.

7.The satellite will fragment and burn up as it falls through the earth's atmosphere.

8.The satellite will observe objects that are particularly interesting astronomically.

9.A methodology will have to be developed to gradually cover the entire spectrum of technologies.

10.You should probably check this notice at regular intervals as it's likely to be updated soon.

11.The reason for the disaster was engine failure, not human error.

12.Economists are concerned by the low level of economic activity.

4. Answer the questions

1.What rays do we deal with when we listen to a radio program?

2.How are infrared rays referred to sometimes?

3.What rays do we use when we sit under a sun-tan lamp?

4.What kind of rays can we find inside the hospital?

5.Are microwaves used with radar equipment?

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5. Mark the statements as true or false. Correct the false ones

1.These seven types of rays do not differ from each other.

2.Seven kinds of rays are close relatives.

3.We find three types of invisible rays in use in our homes.

4.We meet three types of rays outside the home.

5.These seven types of rays differ from each other in their frequency.

6.The frequency is the number of cycles in a second.

7.Radio waves have the highest frequency.

6.Find the information explaining why we call light a visible ray. Read the information to your partner

7.Name the types of invisible rays we find in use: a) in our homes;

b)outside the home

Word Building

8. Give the initial words of the following derivatives

Example: different -to differ

1.communication

2.cooker

3.technological

4.invisible

5.equipment

6.vibration 7.quickly 8.responsible

Grammar

9. Read the following sentences and say which of them are in the Active and which are in the Passive Voice. Translate them into Russian

1.While the experiment was being carried out nobody left the laboratory.

2.A new type of computing equipment is being produced at our plant.

3.At present scientific work is being done mostly by large groups of researchers.

4.The apparatus will be working when you come.

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5.The scientists who are carrying out research into nuclear physics deal with the most difficult problems.

6.For twenty minutes the air in the laboratory was being purified by two ventilators.

7.The solar battery is converting the energy of sun rays directly into electric energy.

8.This experiment was being carried out under low pressure.

9.For a long time the electronic devices were being used for control.

10.An interesting research in the field of electronics is being done at our Institute.

11.Prospects of the usage of solar energy are already understood by everybody.

12.Now solar energy is being studied by a lot of research groups.

13.We were looking for a more simple method of solution but could not

find it.

14.The engineers will discuss the advantages of this new system.

15.Our laboratory is housed in an old building.

10. Translate the following word groups. State the tense and the forms of the predicates

1.the lecture started

2.the scientists are obtaining

3.the colleagues realized

4.the satellite was on its orbit

5.the properties depended

6.the stream is being broadcast

7.the chemist was searching

8.a new technology was demonstrated

9.the elements constituted

10.the student was being examined

11.new results were being obtained

12.the discovery established

Speaking

11. Speak about the electromagnetic waves.

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12. Find some information about the inventors mentioned in the text above. Prepare the presentation about one of them.

Writing

13. Write the summary of the text "Types of Rays".

Lesson 3. Radio Waves

Preview

Before you read

1.What do you know about the methods of radio broadcasts today?

2.What were the first microwaves made by man like?

1. Read the text

Radio Waves

During the last few decades, a subtle change has occurred which none of our senses can register. Radio waves, bearing messages in many tongues,

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flow ceaselessly around us, through us and above us. We can only hear and see them if we convert them to other waves to which our ears and eyes are receptive.

Radio waves are the longest members of the family of electromagnetic waves. In the spectrum, in which the waves are arranged in order of increasing wavelength, they lie beyond the infrared waves. Their wavelengths range from about three hundredths of a centimeter to about 300 kilometers. Radio broadcasts today are made by two different methods known as AM (amplitude modulation) and FM (frequency modulation). The frequencies of the waves used) are expressed in kilocycles or megacycles. The vibrating current is fed into an antenna from which the radio waves are broadcast into space.

Microwaves are the smallest radio waves. In the spectrum of electromagnetic waves they lie between infrared rays and the long radio waves. The shortest microwaves have a wavelength of about three hundredths of a centimeter and a frequency of one million megacycles. The longest microwaves have a wavelength of about three meters and a frequency of one hundred megacycles.

The first microwaves made by man were the two-foot waves produced by Heinrich Hertz. It is interesting that they were the last to be put to a practical use. Long waves were easier, to produce and send out over long distances. Scientists had to return to the use of short waves in order to solve a problem that came up during World War II. The problem was "How can you detect an approaching enemy plane while it is still far away?" A possible answer to the problem was to send a beam of radio waves. Long radio waves could not be used for this purpose because they fan out too quickly from the broadcasting antenna. Very short waves were necessary to make the radar system work. So new transmitters and receivers were designed to make and use microwaves.

After-reading tasks

2. Answers to the following questions

1.Can we hear and see radio waves?

2.What place do radio waves occupy in the spectrum of electromagnetic waves?

3.Who produced the first microwaves?

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4.Were the microwaves the first to be put to a practical use?

5.What kind of problem came up during World War II?

3. Match up the words which are opposite in meaning.

Word Building

4. Read the words and say what suffixes they have and what parts of speech they belong to.

1.use, useful, usefulness;

2.invent, inventor, invention;

3.transmit, transmitter, transmission;

4.work, worker;

5.special, specialty, specialist;

6.practice, practical;

7.contain, container;

8.lecture, lecturer;

9.create, creative, creation;

10.accelerate, acceleration, accelerator;

11.determine, determination;

12.proper, properly, property;

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13.science, scientific, scientist;

14.discover, discovery, discoverer;

15.important, importance;

16.react, reaction, reactor, reactivity;

17.arrange, arrangement;

18.capable, capability;

19.apply, application.

Grammar

5. Translate the following sentences into Russian paying attention to the predicates in the Perfect Passive.

1.This theory has been used for analyzing the experimental data.

2.In my opinion this result has not been proved by anybody.

3.The apparatus used in our research has been described recently.

4.We must compare our data with those that have been obtained by other investigators.

5.Many difficulties had been overcome before the researcher succeeded in his work.

6.After the new device had been tested it was installed in our laboratory.

7.The construction of this television centre will have been completed by the end of the next year.

8.In our country great progress has been achieved in developing all branches of science and engineering.

9.Many different devices have been created in order to improve the performance of communications.

10.The information has been based on the data received from a com-

puter.

11.Much research has been carried out in order to establish the causes of this phenomenon.

12.This question has already been discussed at the conference.

13.By the end of the year a large variety of semiconductor devices will have been produced.

14.This equipment had been repaired before you came.

15.This text has just been translated.

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