Satellite Basics



What types of satellite systems are there?

There are two types of satellite systems in the market today. The first satellite systems were C-band systems; however, over the last two decades, the introduction and expansion of DTH systems has revolutionized the market.

C-Band Satellite Systems...

DTH (Direct To Home) Systems...

 
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What is DTH and how does it work?

DTH (Direct To Home) is a satellite-aided TV rebroadcast system, featuring a compressed digital encoded signal for uplink/downlink.

The first step in creating the digital satellite system is to raise the satellites. This requires a launch missile to raise it to a low-earth geosynchronous orbit (18,000 mph at 22,500 miles). "Geosynchronous" means that the satellite maintains a constant position relative to the earth. A geosynchronous orbit ensures that the antenna does not need to be re-positioned. Each DTH satellite has at least 16 transponders, and each transponder has multiple channels possible because of the digital signal compression and alternately using polarization.

With the satellites in place, a DTH broadcast requires an Earth station for uplink. "Uplink" refers to sending data up to the satellite, which then retransmits the data down (downlink) along a particular angle.

In order to receive DTH, you need the following components:

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DTH Antenna

The DTH antennas have a narrow beam width, which means exact pointing within three degrees is critical. If you are self-installing your antenna, you can get information on aiming the antenna (based on your zip code and dish type) by clicking on the link for DISH Network™ DTH Systems

There are two settings required for aiming a round (18") antenna, and three settings required for using an elliptical (18" x 24") antenna:

18" Round Antenna requires:

18" x 24" Elliptical Antenna requires:

When the antenna is properly pointed, the dish "catches" the signal and reflects it to the LNB (included with the purchase of the antenna).

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DTH LNB (Low Noise Block)

The LNB is the component which sits out in front of the antenna on the LNB arm. It is a signal converter which converts the Ku-band signal from the satellite to a 3.7 GHz - 4.2 GHz signal which is sent to the cable outputs on the LNB, using a band pass filter and an amplifier. Each LNB can only operate on one polarization setting at a time. Alternate polarization is used to separate adjacent channels to prevent interference, which is why you need a Dual LNB to view both odd and even channels at the same time.

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DTH Receiver

The receiver is connected to the LNB via 75-ohm Coaxial cable and tunes the radio frequencies to receive and display each channel. For proper operation, the receiver should have a valid access card and a telephone line installed. The card contains a microprocessor, which supplies the decoding sequence for the receiver and controls channel access and billing. The telephone line allows for data update from the service provider and is required in order to receive pay-per-view events.

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What You Will Need

The number and type of each equipment type that you will need will depend on your viewing requirements:

Viewing Requirements LNB Receiver Additional
Single Television Single Single In-line Amplifier (if cable run is greater than 100 feet)
Multiple Televisions
   -all showing same channel
Single Single Splitter and In-line Amplifiers (as needed)
Multiple Televisions (up to 4)
   -independent channel tuning
Dual 1 per TV Powered Multi-switch and In-line Amplifiers (as needed)
Adding Local Stations via Local Antenna     Local Antenna
Splitter/Combiner (2)
 
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Which DTH system?

RadioShack offers DISH Network™ satellite systems. 

DISH Network equipment can be either purchased or leased.
DISH Network offers a wide range of international programming.
DISH Network offers around 500 channels.
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Features of DISH Network™:

 
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Features Specific to DISH Network™

DISH Network customers can choose to lease their satellite system equipment rather than purchasing it.

In addition to Alaska and Hawaii, DISH Network also provides service to consumers in Puerto Rico.

DISH Network offers the following International packages:

DISH Latino Arabic Language Packages Polish Language Package
DISH Latino Dos Chinese Language Package Russian Language Package
DISH Latino Max Greek Language Packages South Asian Language Packages

DISH Network also offers the following individual channels:

TV Globo International - Brazilian
Record International - Brazilian
RTP - Portuguese
RFI - French
TV5 - French
Radio Maria Italy - Italian
RAI - Italian
TVN24 - Polish
Radio Maria Poland - Polish
POLSAT 2 - Polish
Antenna - Greek
ERT - Greek
Mega Cosmos - Greek
The Israeli Network - Israeli
Phoenix - Chinese TV Japan - Japanese B4U - South Asian
Z Gold - South Asian
BVN TV - Dutch Arirang TV - Korean
    PTV Prime - Pakistani Radio Maria Spain - Spanish

The satellites used for DISH Network programming are owned by EchoStar Corporation. There are four satellite locations (at 61.5º, 110º, 119º, and 148º) and eight satellites, providing over 500 channels.

Satellite Location Transponders Channels
EchoStar 1 148º 16  approx. 100
EchoStar 2 119º 16 approx. 100
EchoStar 3 61.5º 32  75
EchoStar 4 119º 32  75
EchoStar 5 110º 32  approx. 150
EchoStar 6 119º 32  approx. 150
EchoStar 7 119º 32  
EchoStar 8 110º 32  
 
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How do I buy a DTH system?

Because of activation and installation issues, DTH satellite systems are not sold on-line at this time. To purchase or lease a DTH system, you should contact your local RadioShack store.
 
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What satellite equipment and accessories are available?

RadioShack's catalog of DTH products is available under the Satellite section of TV,Satellite & Video.


Can I install my system myself?

Installation is included in the purchase of a DISH Network satellite system. After you have received your equipment  professional installer will install it for you by appointment. If you prefer to install it yourself, a number of accessories are available at your local RadioShack Store.


Equipment and Accessories:

Wireless Phone Jack (Cat. No. 430-0160)

In-line Signal Amplifier (Cat. No. 160-1156)

Grounding Block -- Single (Cat. No. 150-909) or Dual (Cat. No. 150-920)

Grounding Rod -- 4' (Cat. No. 150-0530) or 8' (Cat. No. 150-0529)

Grounding Wire -- 40' 8-gauge Aluminum Wire (Cat. No. 150-0035)

Coax Weather Boot (Cat. No. 278-1658) and Silicone Rubber Sealant (Cat. No. 640-2314)


Tools


Cables

Good - 75-Ohm Coaxial with "F" Connectors with Weather-proof Connectors / requires Ground Wire above

Better - 75-Ohm Coaxial with "F" Connectors / requires Weather Boot above

 
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Glossary

 

Adapter, Connection:
A device which converts one type of plug or jack to a different plug or jack.
  
Amplifier, In-line:
Used to increase signal strength; compensates for signal loss due to splitters, adapters or cable runs over 100'.
  
Antenna:
A device designed to receive, transmit or receive and transmit particular frequencies.
  
Antenna, Local Broadcast:
Also called "off-air", this is a term used to describe standard television antennas, which are designed to receive signals which are broadcast from an earth station to the antenna.
  
Antenna, Satellite:
A dish and an LNB.
  
Azimuth:
The side-to-side angle on a satellite antenna.
  
Cable Run:
The length of cable between a satellite antenna and a receiver.
  
C-band:
The frequencies from 3.7 GHz to 7 GHz, often used to describe the older (usually 5' to 9' diameter) satellite antennas, which operate between 3.7 and 4.2 GHz.
  
Decoder:
A device which is connected between a receiver and the television, enabling the user to decode scrambled signals (the decoder is built into DTH satellite antennas).
  
DISH:
The circular or oval concave part of the satellite antenna which reflects and focuses the signal onto the LNB.
  
DISH Network™:
A DTH satellite system service provider. The "DISH" in "DISH Network" is an acronym for "Digital Sky Highway".
  
DNS:
Acronym for "Distant Network Service", which allows the consumer to have DTH capability in either an RV or a commercial truck.
  
Downlink:
Data being sent from a satellite down to an earth station.
  
DTH:
Acronym for "Direct To Home"; refers to home-based satellite systems.
  
Earth Station:
A ground-based antenna and equipment designed to either transmit data to or receive data from a satellite.
  
Elevation:
The up/down angle on a satellite antenna.
  
Geosynchronous:
Describes a satellite orbit which maintains a constant position relative to the Earth.
  
Ku-Band:
The frequencies from 12 GHz to 14 GHz, often used to describe DTH satellite antennas, which receive the frequencies from  11.7 GHz to 12.2 GHz.
  
LNB:
Acronym for Low Noise Blocker, the part of a satellite antenna which is positioned in front of the dish to receive the signal and converts the signal to be carried by cable to the receiver.
  
LNB Arm:
The metal arm which physically connects the LNB to the dish.
  
LNB, Dual:
An LNB with two output connections.
  
LNB, Single:
An LNB with a single output connection.
  
Multi-switch:
A device which allows you to have up to four receivers connected to a single satellite antenna, with each receiver capable of independent tuning. This device requires that you have a Dual LNB satellite antenna, and can also be used as a combiner if a broadcast antenna is connected. If a TV antenna is connected, you would need to use a Splitter/Combiner at each receiver to split the output into separate TV antenna and DTH signals.
  
Pay-per-view:
Movies or other special programming events which must be purchased individually.
  
Polarization:
The alignment or orientation of the waves of a signal (either circular or linear).
  
Receiver, Satellite:
A device which is connected to and receives the signal from the LNB via cable and converts it to a standard Audio/Video signal. DTH receivers have built-in decoders; older C-Band receivers may require a separate decoder.
  
Satellite:
A piece of equipment which is launched into orbit for various purposes, often to receive and/or transmit a particular signal. Many types of satellites, including those designed to retransmit DTH signals, are placed in geosynchronous orbits, allowing a satellite antenna to be positioned to receive the signal without the need for periodic re-positioning or re-aiming of the antenna.
  
Satellite System:
A satellite antenna and a corresponding receiver. Older C-band systems may also include a decoder.
  
Splitter:
A device with one input and two or more outputs which splits the signal into two or more signals, each which has a lower signal strength than the original signal (unless the splitter includes an amplifier or is part of a splitter/combiner).
  
Splitter/Combiner:
Combiner: Used to combine two different signals which operate on different frequencies (such as from a broadcast antenna output and a satellite antenna) into a single signal carried on a single cable, to simplify running the cable from the antenna(s) and the receiver(s).
Splitter: A specialized splitter used to to split the combined signal back into the two original signals to allow each signal to be connected to the correct input on the receiver.
  
Tilt:
The degree of circular rotation on a satellite antenna.
  
Transponder:
A "channel" on a satellite with a specific bandwidth and uplink/downlink frequency.
  
Uplink:
Data transmitted from an earth station to a satellite.
 
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