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- Free to Air
Satellite -
Free to air satellite systems can be defined as a satellite
system primarily designed to receive "in the clear" or
unscrambled satellite broadcasts. At the present time, there are
literally hundreds of channels of news, sports, networks, special
interest programming and ethnic channels and foreign language
channels that are available without a subscription. The selection
is also constantly changing, with new channels coming online and
some old ones going offline or changing their broadcast schemes.
In the past 5 years, most broadcasters have switched their
broadcasts to digital, although there are still a number of
analog broadcasts, mostly in the C band range that are
available.
Introduction
The concept of receiving free to air satellite signals dates
back to the inception of satellite broadcasts in the mid 1970's
and 1980's where large C/Ku band satellite systems were a popular
way of tapping into hundreds of available channels from the sky.
The downside to these systems were extremely large dish sizes and
expensive equipment. These made satellite systems prohibitive for
many people. However over the years, increasingly powerful
commercial satellites and improvements in technology have brought
prices and dish sizes down quite dramatically.
The mid 1990's saw the introduction of digital direct to home
technology, which for the first time allowed main stream users to
access a wide variety of channels not available via their local
cable company, while enjoying incredible picture and sound
quality, all from a dish far smaller than had ever been seen
before. The small dish revolution nearly caused the extinction of
the large dish industry, which simply could not compete on dish
sizing, price or ease of installation.
The late 1990's saw the digital revolution spread to the large
dish industry with services such as 4DTV which brought the same
digital picture and sound as the small dish systems to large dish
users, although a new and expensive decoder was required for
reception.
The last several years has seen most broadcasters switch their
broadcasts to digital, which allowed broadcasts to be compressed,
allowing more channels per satellite transponder and also a
superior picture and sound quality. As well, a common digital
standard known as MPEG2-DVB has been adopted by many
broadcasters, which allows all free to air satellite channels that use the
DVB (Digital Video Broadcast) standard to be received from one
satellite decoder.
Over the years, the free to air market has slowly begun to see
a small comeback, primarily due to an abundance of programming
not available anywhere else, such as international and foreign
language channels as well as improved picture and sound
quality.
Required Components
There are a number of components necessary for free to air satellite
reception, some are mandatory and others are optional.
Clear line of sight to the
satellites
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In order to properly receive free to air satellite signals,
you must have a clear view to the satellites. In North America,
you need to have a relatively clear view to the southern sky.
Obstacles such as tall buildings or trees or mountains will
severely impair or make reception impossible. If you are only
interested in signals from one or two satellites, you will more
than likely be able to locate your dish in a location favorable
to reception of the desired satellite. If however you wish to
receive multiple satellites, you will need an unobstructed view.
A do it yourself site survey with a compass and a satellite
location chart or a professional satellite site survey will
determine your eligibility for free to air reception.
Dish
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In order to receive most Ku band signals in North America, you
will require a minimum of a 30"(75cm) Ku band satellite dish
antenna. For fringe area reception or reception of signals
outside of a satellite footprint, or locations with an abundance
of trees, you will need to upgrade to a larger dish size.
Additionally, if you live in an area prone to heavily rain
showers, you may want to consider a larger dish diameter as
weather can adversely affect satellite signal quality. If you
also wish to receive the low power C band signals, you will need
a much larger (6-10') C band dish and a more elaborate setup.
Your dish must be installed in a location where it will not be
prone to excessive movement. Smaller dishes, such as 30" can be
mounted to a building or roof. Larger dish sizes should probably
be mounted to a firm pole in the ground, reinforced with
concrete.
LNBF/LNB
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The LNBF or LNB is the device at the end of the dish arm that
collects the signal, amplifies it and sends it to the receiver to
be decoded. Ku band systems use an LNBF(Low Noise Block Amplifier
with integrated Feed) and large C band systems use an LNB(Low
Noise Block Amplifier) with an external feedhorn. Most dedicated
Ku band systems use offset dishes, meaning the dish is designed
in such a way that the LNBF is offset towards the bottom of the
dish so as not to interfere with the signal. This allows a
smaller dish size as opposed to large C band systems which locate
the LNB at the focal point or center of the dish which tend to
block out a portion of the incoming signal. Quality of the
LNBF/LNB is paramount. Ku band LNBF's are measures in
DB(Decibals). A good quality Ku band LNBF will have a rating not
above .6db. A superior one will be .5db or lower. C band LNB's
are measured in degrees. A good quality C band LNB will have a
rating of 17 degrees of below. There are also 2 distinct types of
Ku band LNBF's. LNBF's designed for use with direct to home
satellite services such as Directv or Dish Network which use
circular polarization and are not compatible with free to air
satellite signals. For all free to air signals, you will want a
linear Ku band LNBF as conventional Ku satellites use
linear(horizontal or vertical) polarization.
Actuator/Rotor
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Also known as a satellite dish positioner or dish mover, this is the
electric motor device that moves a dish from left to
right(azimuth) and up and down(elevation) in order to receive
programming from multiple satellites. If you only are interested
in programming from a single satellite, you will more than likely
not require one of these devices as your satellite dish will be fixed in
one constant position. However if you wish to receive signals
from multiple satellite, you will need a dish positioner. Most
recent quality receivers now come with a feature known as
DiSEqC(Digital Satellite Equipment Control), which can control a
dish positioner directly. However if you have an older satellite
receiver than does not support this feature, you will likely need
to purchase a seperate dish positioner control if you wish to
track multiple satellites.
Free to Air Satellite
Receiver
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This of course is the most important part of your system.
There are currently several different digital broadcast formats,
however most free to air broadcasts use the common MPEG2-DVB
format. When selecting a satellite receiver, you will want to
ensure that you are choosing a receiver that decodes the correct
format. If you reside in Europe, many pay broadcasters such as
Irdeto, Viaaccess, Nagravision, Mediaguard, Betacrypt also use
the MPEG2-DVB format and you can receive these signals(upon
subscription) if you select a receiver that supports a common
interface module which is a removable module that allows for a
smart card which is required for reception of various European
pay services. Additionally, a number of foreign pay channels
receivable in North America can be decoded using a common
interface and a subscription. If you intend on using your DVB
receiver for pay programming, you will need a smart card and a
subscription, both of which are available from the satellite
service provider. North American direct to home services cannot
be received via a DVB receiver as they use proprietary equipment.
Common interface modules are due to laws in several European
countries that forbid sales of proprietary satellite receivers
that are locked into a single service. However, for most North
American free to air applications, you will need little more than
a quality free to air receiver. If you wish to record your
programming, you may wish to invest in a free to air receiver
with a integrated personal video recorder(pvr), allowing for
dozens of hours of recorded programming. Additionally, there are
a number of things to be taken into consideration when choosing a
satellite receiver. Some retail outlets offer European DVB
satellite receivers. While these will work with North American
signals, some are not pre-programmed with the locations of North
American satellites as are most receivers designed for North
American users and most come equipped with connections that are
for the most part inapplicable here in North America, such as
SCart connections and different coaxial connectors. As well, not
all receivers are created equal, many have features that others
do not. For example, if you are interested in good sound quality,
then you will want a receiver with a Dolby Digital or AC3
connection. Not all receivers are equipped with this. As well,
you will likely want a receiver equipped with an S-Video or at
the very least composite video and audio connections. Also if you
are interested in looking for hard to find channels or "wild
satellite feeds", then you may want to invest in a receiver that
has a blind search function which will scan an entire satellite
for all channels on all bands. As well, you will want to ensure
that your receiver has a fairly fast processor, some can take
1.5-2 seconds to change between channels which can be painful,
especially if you are used to DTH systems which are relatively
fast.
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09/19/2007 12:08 AM
Welcome to our new site. digitalinsurrection.com is now lounge0101.com. Please excuse our mess as we complete a long overdue redesign of our website. The new primary url of our website is now www.lounge0101.com. Please update your bookmarks. With the redesign, you will find all areas of the website have been updated. Stay tuned for more coming soon.
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