Чтение общенаучной литературы. Кытманова О.А. - 27 стр.

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stripes are fast replacing the older shadow mask tube Flat panel screens using
solid-state techniques instead of cathode ray tubes have been developed
Miniature television sets use liquid-crystal displays like those used in
calculators and digital watches.
A color is made up of three elements luminance or brightness, hue which is
redness yellowness and so on and saturation or intensity .From the signal that the
television receives these elements can be reconstructed to give a faithful picture
Cable Television
Television is increasingly used for observing processes that cannot be approached
closely For instance the furnaces and pressure gauges in a power plant may be
''watched" by a television camera which sends its pictures to a central control
room. Television can also be used to watch and control the pouring of large
castingsinfoundries and the movement of radioactive substances .It is also used to
watch the behavior of rocket and jet engines undergoing tests, and for salvage
operations on sunken ships. It can be used to give medical students in a lecture
room a close up view of surgical operations taking place in another part of a
hospital and for many tasks in scientific research .Television cameras connected to
sets in a central security office can act as electronic "guards".
This kind of television is called "closed circuit' and is useful over short distances
Cables connect the camera to the receiver This is the kind of television system you
sometimes see in large stores.
Cable television can also be used to bring programs into the home. By combining
a cable network on the ground with satellite relays in space, a viewer can pick up
programs from all over the world paying a fee for whatever cable channel is
chosen for viewing. To send programs over
long distances, the television signals
normally have to be "boosted" a network of
relay stations. If you live more than 80
kilometers (50 miles) or so from a
transmitter your broadcast television picture
may be rather poor .This is because the
signals travel in straight lines and, owing to
the curvature of the Earth, travel away from
the surface and out into space
Worldwide Television Networks.
Increasingly powerful communications
satellites arc being sent into space making it
possible for viewers to see events as they are
happening in distant countries. There are
regular transatlantic broadcasts between the United States and Europe, and
Eurovision is the name for the network of microwave radio and cable links
throughout Europe. The DBS (Direct Broadcasting by Satellite) system, which
enables direct broadcasting of television programs from a satellite into the home is
available in several countries.

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