EXERCISES
1. Review questions:
1, What is the primary purpose of the oscillograph?
2. What are the essential parts of the oscillograph and TV receivers? 3. What current is the oscillograph supplied with? 4. What does the amount of deflection depend upon? 5. What for is a saw-tooth waveform used? 6. How is a steady image obtained?
II. Make up an abstract of the text basing on the answers to the above questions.
III. Translate the international words without a dictionary: pulse, period, amplitude, 'interval, diagram, synchroni zing, information, moment, oscillograph
IV. Define what parts of speech these words are and trans late them:
investigator, receiver, primary, invisible, essential, successive, initial, unnecessary, beginning, increment, retrace, superposition, reproduce, disappear, deflection, accurately
V. Translate these synonyms and memorize them:
1. image (n), representation
2. period (я), time, cycle
3. steady (adj), fixed, stable
4. device (n), gadget, instrument
5. supply (v), furnish, provide
6. show (v), indicate, illustrate, demonstrate
7. investigate (v), research, explore
8. accurately (adv), exactly
9. hence (adv), so, then, therefore, consequently 10. appear (v), become visible
VI. Translate these words and word combinations and learn
them:
besides, the same, in order to, relatively, provided, thereby, such, how, along, any
Test 1
Find the correct answer out of the three given to each question:
1. Which of the following tubes converts an electrical sig nal into a visual one:
a diode tube, a triode tube, a cathode-ray tube
2. In which of the following devices a cathode-ray tube is used:
a radio-receiver, an ac amplifier, an oscillograph"
3. Which of the following particles are to be removed from the cathode-ray tube when it is operating: electrons, neutrons, gas molecules
4. By means of which of the following fields the electron deflection is produced in the above mentioned tube:
a magnetic field, an electrostatic field, the combination of magnetic and electrostatic fields
5. Which of the following parts of the cathode-ray tube is used for producing a narrow beam of electrons:
an electron gun, plates of the deflecting system, a fluorescent screen
6. Which of the following parts of the cathode-ray tube the investigated signal enters:
the electron gun, the vertical deflecting plates, horizontal deflecting plates
Test 2
I. Find Russian equivalents for the English verbs (see p. 148):
1. mount (а) желать
2. combine (b) считать, рассматривать
3. deflect (с) случаться, появляться
4. consider (d) помещать
5.adjust (e) производить
6. place (f) объединять(ся)
7. desire (g) сокращать
8. abbreviate (h) отклонять(ся)
9. produce (i) монтировать 10. occur (j) регулировать
II. Find Russian equivalents for the English words and word combinations (see p. 148):
1. readily (а) иначе
2. otherwise (b) посредством
3. let us (с) среди
4. in effect (d) легко
5. among (e) после; после того как
6. such as (f) давайте
7. by means of (g) такой как; как например
8. after (h) как... так и
9. both... and (i) иногда, случайно 10. occasionally (j) в действительности
III. Find Russian equivalents for the English words and word combinations (see p. 148):
1. besides (а) тот же, самый
2. in order to (b) при условии, если
3. the same (с) такой
4. provided (d) кроме того, помимо
5. such (e) любой
6. how (f) относительно
7. relatively (g) вдоль, по
8. any (h) посредством этого
9. along (i) как
10. thereby (j) для того, чтобы
IV. Match these synonyms (see pp. 148):
1. give off (a) in effect
2. means (n) (b) emit
3. hence (c) stable
4. speed (d) precise
5. steady (e) highly
6. period (f) velocity
7. accurate (g) rapidly
8. in fact (h) therefore
9. quickly (i) cycle 10. very (j) way
Test 3
Find a synonym (a), (b), (c) or (d) to the word or word combination in bold type:
1. The process takes place — (a) shows; (b) indicates; (c) means; (d) occurs
2. To accelerate electrons — (a) conduct; (b) focus; (c) emit; (d) speed up
3. To regulate a device — (a) produce; (b) fix; (c) ad just; (d) construct
4. To choose a conductor — (a) apply; (b) use; (c) con nect; (d) select
5. A broad beam — (a) long; (b) wide; (c) light; (d) short
6. An electron beam — (a) flow; (b) ray; (c) gun; (d) device
7. To indicate the polarity — (a) represent; (b) show;
(c) use; (d) provide
8. To guide electrons — (a) liberate; (b) conduct; (c) give off; (d) accelerate
9. A difficult job — (a) task; (b) work; (c) situation;
(d) position
10. The applied technique — (a) machine; (b) instrument; (d method; (d) device
11. To consist of elementary particles — (a) knock out;
(b) depend 6n; (c) find; (d) be made up of
12. To investigate the voltage — (a) research; (b) deter mine; (c) know; (d) measure
13. A highly sensitive device — (a) good; (b) new;
(c) very; (d) modern
14. Several devices — (a) a lot of; (b) the same; (c) five;
(d) a few
15. The battery supplies energy — (a) uses; (b) changes; (c) furnishes; (d) adjusts
16. To move rapidly — (a) in the same way; (b) quickly: (c) slowly; (d) quietly
17. Accurately obtained trace — (a) usually; (b) earlier; (c) exactly; (d) previously
18. The image of the input signal — (a) form; (b) speed; (c) period; (d) representation
19. The essential part of — (a) main; (b) other; (c) sec ond; (d) last
20. The same kind of matter — (a) work; (b) substance; (c) energy; (d) voltage
Test 4
Finish each sentence choosing one of the three variants (a),
(b) or (c) based on the texts from Section V: 1. Cathode-ray tubes provide...
(a) the generating of the sound waves; (b) amplification of low electrical signal; (c) a visual representation of voltage and current waveforms.
2. Cathode-ray tubes consist of...
(a) one basic component; (b) two basic components; (g) three basic components.
3. One of the essential parts of a cathode-ray tube is...
(a) an electron gun; (b) a source of positive voltage; (c) a transistor amplifier.
4. A narrow beam produced by an electron gun accelerates focuses and consists of...
(a) positive ions; (b) electrons; (c) protons,
5. A deflection system...
(a) produces electrons; (b) deflects the electron beam; (c) is the source of electrons.
6. A fluorescent screen produces...
(a) an electron beam; (b) an alternating current; (c) a spot of visible light. 7. The fluorescent screen is covered with...
(a) fluorescent materials; (b) conducting coating of carbon particles; (c) a thin copper coating.
8. The essential parts of a cathode-ray tube are housed in...
(a) a hollow cylinder; (b) a glass envelope; (c) a metal box.
9. The method used for removing the electrons from the screen and returning them to the cathode is...
(a) to place the Aquadag coating; (b) to remove the cathode; (c) to place an anode battery.
10. The essential part of all oscillograph and TV receivers is...
(a) a transistor oscillator; (b) a cathode-ray tube; (c) a generator of the alternating current.
11. The primary purpose of the oscillograph is to convert...
(a) electric signals into visual images; (b) an alternating current into a direct current; (c) a saw-tooth waveform into a sinewave.
12. The oscillograph comprises, besides the cathode-ray tube...
(a) a sinewave voltage oscillator; (b) the scanning, deflection and synchronizing circuits; (c) a tube tank circuit.
13. The electron gun of the cathode-ray tube of the oscillo graph is supplied with...
(a) dc voltage; (b) ac voltage; (c) a dumping sinewave.
14. The voltage of the signal investigated enters...
(a) the horizontal deflection input of the amplifier;
(b) the vertical deflection input of the amplifier; (c) the filament circuit of the cathode-ray tube.
15. The amount of vertical deflection depends on...
(a) the strength of the current of the cathode-ray tube;
(b) the input signal of the horizontal amplifier;
(c) the voltage of the output signal of the vertical amplifier.
16. Scanning is accomplished by...
(a) deflecting electron beams along the horizontal line;
(b) changing the filament voltage of the cathode-ray tube;
(c) changing the amount of electrons getting on the
fluorescent screen.
17. A waveform that provides the relatively slow linear rise in amplitude and rapid retrace to zero has the ap pearance of...
(a) the straight line; (b) the sinewave; (c) the teeth of a saw.
18. A waveform that has the appearance of the teeth of a saw is called...
(a) a saw-tooth waveform; (b) a dc voltage waveform;
(c) a sinewave.
19. To obtain a steady image on the oscillograph screen it is necessary...
(a) to change sharply the filament voltage in accordance with the
input signal;
(b) to overlay most accurately the previously obtained trace;
(c) to reduce the light spot on the screen of the oscillograph.
20. Superposition can be obtained only, provided...
(a) the input signal is slowly changed;
(b) the sawtooth voltage is absent;
(c) each sweep coincides with the beginning of each
successive period of the input signal.
(See keys to the tests on p. 148)
Translate into Russian without a dictionary.
TEXT
1. Cathode-ray tubes convert an electrical signal into a visual one by shooting a beam of electrons at a fluorescent screen and deflecting the beam in accordance with the variations of the electrical signal. Cathode-ray tubes consist of an electron-gun, a deflection system, and a fluorescent screen, all housed in a glass envelope.
2. The electron gun — usually made up of a heater-type cathode, a control grid, an accelerating electrode or grid, a focusing anode, and a final accelerating anode — produces, accelerates and focuses the emitted electrons into a narrow beam. It acts as an electron emitter and electronic lens system.
3. The fluorescent screen is coated with a phosphor zinc silicate, zinc oxide, zinc sulphide that produces visible light when electrons impinge on it.
4. The oscillograph comprises the cathode-ray tube, the scanning, deflection and synchronizing circuits. It is supplied with a direct current. The oscillograph converts electric signals into visual images. To obtain a steady image on the oscillograph screen it is necessary for each trace produced in each period of scanning to overlay most accurately the previously obtained trace.
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