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How are
Satellites possible?
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Satellite
broadcasting is made possible by the fact that communications
satellites are fixed in geosynchronous orbit 22,300 miles above
the equator, staying in the same position above the ground at
all times. This allows satellite antennas that transmit and
receive signals to be aimed at an orbiting satellite and left in
a fixed position.
Satellite
programmers broadcast, or uplink, signals to a satellite which
they either own or lease channel space from. The signals are
often scrambled, or encrypted, to prevent unauthorized reception
before they are retransmitted to a home antenna. The uplinked
signals are received by a transponder located on the satellite,
a device that receives the signals and transmits them back to
the earth after converting them to a frequency that can be
received by a ground-based antenna. Typically there are 24 to 32
transponders on each satellite. In order to minimize
interference between the transponders, the signals are
transmitted with alternately polarized antennas. Each satellite
occupies a particular location in orbit, and operates at a
particular frequency assigned by the FCC.
The
signals received at the satellite from a ground-based antenna
are extremely weak in amplitude – much less than one watt. As
a result, they must employ amplifiers that boost the signals to
a level that can successfully be processed and retransmitted to
the earth. After traveling 22,000 miles to a ground-based
antenna, the signals are again very weak and must be amplified.
Therefore, satellite “dishes” focus the signals onto the
actual antenna. The signals from the antenna are then fed to a
“low-noise block,” or LNB, amplifier which amplifies signal
and converts them to a lower frequency. The lower the power of
the satellite, the larger the antenna required to focus the
signals. A C-Band satellite, with power ranging between 10 and
17 watts per transponder, typically has an antenna between 5 and
10 feet in diameter; whereas a high-powered Ku-Band satellite,
with a range of 120 to 240 watts per transponder, only requires
an antenna 18 inches in diameter. The signals from the antenna
are fed to an integrated receiver/decoder (IRD), which converts
them to a form that can be viewed on a standard TV set. Every
IRD contains a unique address number, which is activated by a
installer/consumer to allow it to receive subscription services.
In addition, the IRDs modem port is connected to a telephone
line, in order to access pay-per-view ordering services and
transmit other data. A single IRD can supply one channel choice
to one or more TV sets. In order to view two different programs
at the same time on two different TV sets, two IRDs are
required—one for each TV, and the antenna must be a dual-LNB
type.
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Satellite Home Viewer Improvement Act (SHVIA)
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Since
the passing of the Satellite Home Viewer Improvement Act (SHVIA)
in 1999, satellite TV companies have begun to offer local
programming to many areas throughout the
United States
. For those areas where local TV signals are not being offered
via satellite, satellite systems offer built-in electronic A/B
switches. With a single push of a button on the remote control,
consumers can toggle between satellite and off-air or cable TV
signals.
Satellite
TV offers a distinct technological advantage over cable TV
systems: cable operations are essentially satellite operations
in that cable networks receive their programming via satellite
but then re-transmit the signals through the cable companies'
trunk lines, which degrade the audio and video signals to a
greater or lesser degree on the way to the customer’s home.
Satellite TV, on the other hand, eliminates the intervening
wiring and provides a direct link from the satellite to the
customer’s antenna in a 100% digital video and audio feed.
A-n-L Unlimited and its installation team have been
installing Directv and DISH Network since these two Companies
launched their first satellites. When you see an A-n-L Unlimited
installer at your home, you know the job will be done right. Our
installers are certified and insured.
Standard installation of
your satellite system is FREE. It’s normally $199.00. Wow, a
savings of $199.00. Included in a standard installation is:
Materials Provided At No Charge:
- Up to
120' RG-6 cable
- Coaxial
cable connectors
- Grounding
equipment
- Weather
sealant for connections and structure
Standard Professional Installation
Includes
- Site
survey (at time of installation)
- Assembly
of dishes and mount(s)
- Grounding
of system components
- System
peaking for optimum performance
- Installation
of up to 120' RG-6 cable
- One wall
cable penetration
- Testing
of equipment for proper operation
- Orientation
to DISH Network programming and equipment
Other products and
services are extra.
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