Satellite TV is a
broadcasting service which allows subscribers to receive television
signals through a dish-shaped receiver unit. These signals are
originally uploaded to a communications satellite that is in a fixed
orbit above the earth, then electronically scrambled to prevent
unauthorized downloading. Those who pay a subscription fee for
satellite TV service are issued both the receiving dish and a
descrambler.
The actual
tuning information is fed into the television through a cable, much
like the earth-bound cable television services in competition with
satellite TV providers.
Satellite TV solves many
of the problems associated with earlier television broadcasting methods.
Television stations originally broadcast their signals in two
specific radio wave bands- VHF (very high frequency) and UHF
(ultra-high frequency). Aerial antennas placed on roofs or attached to
the television itself would receive as much of these radio wave
transmissions as possible, but the results could be barely watchable
depending on the strength of the signal, the terrain between the station
and the television set, and the atmospheric conditions. Cable
television systems could provide a better television signal, but this
involved stringing miles of insulated wire and creating subscription
services.
Satellite TV provides a strong
digital signal to subscribers' television sets and is almost
completely wireless. Earlier satellite TV systems used very large dish
receivers in order to focus the distant signals onto a powered
antenna. Since different television channels were located on different
communication satellites, these dishes would have to physically turn
to predetermined points in the sky in order to receive the proper
signals. Because regulation of these early dishes was not uniform,
illegal electronic descramblers became a lucrative underground market.
Stiffer penalties for unauthorized descramblers paved the way for
legitimate satellite TV subscription services.
Modern satellite TV services have
streamlined the process. A single communication satellite now remains
in a steady orbit above the Earth, allowing all subscribers to mount a
much smaller dish receiver at a fixed point. Technicians from the
satellite TV provider may install the dish or owners can determine the
proper receiving angle and do it themselves. Instead of scanning
various satellites for different channels, modern satellite television
providers license the use of popular cable or broadcast channels. Much
like a cable system, the tuner descrambles selected programs sent out
on a specific frequency. This allows satellite providers the option of
pay-per-view movie rentals or the blocking of adult-oriented or
premium movie channels.
Satellite TV services are especially
popular in rural areas with poor broadcast reception and/or no cable
service. Purchase of a receiving dish is generally limited to
homeowners, not renters. Satellite dishes must have a clear line of
sight to the satellite itself for best reception. Some homeowners
discover that a grove of trees or mountainous terrain can be
problematic. Critics of satellite TV also mention reception problems
during heavy rains or snowfall. Signals between an earth-bound
receiver and a space-based satellite can be affected by atmospheric
conditions between them, but other television services also have
similar drawbacks. Many customers prefer the additional channels
available on satellite TV systems and the clarity of the digital
signals.
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