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EXERCISES
1. Review questions: 1, What is the primary purpose of the oscillograph? 2. What are the essential parts of the oscillograph and TV II. Make up an abstract of the text basing on the answers III. Translate the international words without a dictionary: IV. Define what parts of speech these words are and trans 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 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 a diode tube, a triode tube, a cathode-ray tube 2. In which of the following devices a cathode-ray tube is a radio-receiver, an ac amplifier, an oscillograph" 3. Which of the following particles are to be removed from 4. By means of which of the following fields the electron 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 an electron gun, plates of the deflecting system, a fluorescent screen 6. Which of the following parts of the cathode-ray tube the 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 II. Find Russian equivalents for the English words and 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 III. Find Russian equivalents for the English words and 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 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; 3. To regulate a device — (a) produce; (b) fix; (c) ad 4. To choose a conductor — (a) apply; (b) use; (c) con 5. A broad beam — (a) long; (b) wide; (c) light; (d) 6. An electron beam — (a) flow; (b) ray; (c) gun; 7. To indicate the polarity — (a) represent; (b) show; (c) use; (d) provide 8. To guide electrons — (a) liberate; (b) conduct; (c) give 9. A difficult job — (a) task; (b) work; (c) situation; (d) position 10. The applied technique — (a) machine; (b) instrument; 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 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; 16. To move rapidly — (a) in the same way; (b) quickly: 17. Accurately obtained trace — (a) usually; (b) earlier; 18. The image of the input signal — (a) form; (b) speed; 19. The essential part of — (a) main; (b) other; (c) sec 20. The same kind of matter — (a) work; (b) substance; 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 (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 (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 (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 (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 (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 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 (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 (a) a saw-tooth waveform; (b) a dc voltage waveform; (c) a sinewave. 19. To obtain a steady image on the oscillograph screen it (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. Дата добавления: 2015-09-27 | Просмотры: 1077 | Нарушение авторских прав |