Without understanding the inquiries of pure science we cannot follow the story of radio. Try to remember all information that you know about the radio.
1. It begins with Joseph Henry who discovered that electrical discharges were oscillating. It was in 1842. 2. Than James Maxwell showed that all electrical and magnetic phenomena could be reduced to stresses and motions in a medium, which he called the ether. 3. In 1878 David Hughes found that a loose contact in a circuit containing a battery and telephone receiver would give rise to sounds in the receiver. 4. Than Heinrich Hertz, he was the first to create, detect and measure electromagnetic waves. 5. Marconi invented a system of highly successful wireless telegraphy. 2. Say about A. S. Popov’s contribution to the development of radio. Radio was invented in Russia. The world's first receiver was constructed in 1895 by the great Russian scientist Alexander Popov. There were no transmitters then; therefore his receiver could only pick up signals produced by lightning discharges during a thunderstorm. A. Popov demonstrated a device called a "storm indicator" at a meeting of the Russian Physico-Chemical Society in St. Petersburg on May 7, 1895. This day is marked now as Radio Day. Soon Alexander Popov found a way of transmitting Morse code signals. In 1897 he sent the world's first wireless telegram over a distance of 600 m and four years later the range of transmission was increased to 150 km. Ever since, thanks to the work of many scientists of the world, the methods of transmission and reception have been constantly improved. 3. Match following words and word combinations with the Ukrainian: a) in the early days; inventor; coherer detector; discharge; transmission; broadcasting; net; radio set; oscillate; valve; tune in; to amplify; a)підсилювати; радіомовлення; радіоприймач; когерер; мережа; електронна лампа; колива-тися, генерувати; винахідник; на зарі розквіту; розряд; передача; налаштувати на (хвилю, станцію) 4. Arrange antonyms in pairs and memorize them: a) next to, useful, direct, high, short wave, inside, transmitter, possible, charge, backwards b) discharge, forwards, low, useless, indirect, impossible, far from, outside, long wave, receiver 5. Arrange synonyms in pairs and memorize them: a)change, constant, amount, similar to, rarely, in tandem, amplify, supply, happen, for instance, join b) in series, seldom, provide, alike, quantity, stable, vary, enlarge, take place, for example, couple 6. Put the words in order: 1. could, along, pass, the, electricity, the, air, through, as, well, as, a wire. 2. line, travel, waves, in, a straight, the, radio. 3. the sky, back, waves, are reflected, the radio, to, the, from, earth's, surface. 4. the, travel, around, waves, the, world, radio. 5. radio, waves, out, can, send, also, ultra-short, transmitters, waves. 6. valves, inside, set, your, radio, have, two, uses, other. 7. Fill in the blanks with the following words: Air, alternating, amplify, heaviside, higher, transmit, tune, wireless 1. Electricity passes along a wire, but it may also pass through the....2. A. S. Popov was the first man to send messages by....3. The Appleton layer is the name for the …ceiling in the sky which reflects radio waves. 4. Long waves are reflected by the... layer. 5. Ultra-short waves are used to... messages to spaceships. 6. You can... in to a broadcasting station by turning a tuner of your radio. 7.... current is used to transmit radio waves. 8. Valves… inside your radio the electrical energy received from the transmitter. 8. Complete the following sentences, using active vocabulary: 1. The radio waves travel in a straight line, but they … 2. Electricity could pass through the air as well as… 3. Radio transmitters can also send out… 4. A modern broadcast transmitting station has an…5. Valves inside radio sets oscillate the current from… 6. The valves amplify the very small amount of…7. Radio waves are sent out by… 9. Match terms with the proper definitions: 1.Signal … 2.Gain … 3.Frequency … 4.Channel … a) the increase in signal power in transmission from one point to another under stated conditions b) the number of periods per unit time c) a path along which signal can be sent d) A visual, audible or other indication used to convey information. 10. Give the definitions to the terms: Radio broadcasting.
|
