Television receive-only

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Television receive-only (TVRO) is a term used chiefly in

Sky TV that transmit Ku signals. While these services are at least theoretically based on open standards (DVB-S, MPEG-2, MPEG-4
), the majority of services are encrypted and require proprietary decoder hardware. TVRO systems relied on feeds being transmitted unencrypted and using open standards, which heavily contrasts to DBS systems in the region.

The term is also used to refer to receiving digital television "

People's Republic of China, as many rural locations cannot receive cable television
and solely rely on satellites to deliver television signals to individual homes.

"Big ugly dish"

The term "BUD" (big ugly dish) is a colloquialism for C-Band satellite dishes used by TVRO systems. BUDs range from 4 to 16 feet in diameter, with the most popular large size being 10 feet. The name comes from their perception as an eyesore.

History

The back side of a C-Band satellite dish showing the pole, mount, motor, counterweight, and structure of the dish.

TVRO systems were originally marketed in the late 1970s. On October 18, 1979, the FCC began allowing people to have home satellite earth stations without a federal government license.[1] The dishes were nearly 20 feet (6.1 m) in diameter,[2] were remote controlled,[3] and could only pick up HBO signals from one of two satellites.[citation needed]

Originally, the dishes used for satellite TV reception were 12 to 16 feet in diameter and made of solid

aluminum.[4] Early dishes cost more than $5,000, and sometimes as much as $10,000. The wider the dish was, the better its ability to provide adequate channel reception. Programming sent from ground stations was relayed from 18 satellites in geostationary orbit located 22,300 miles above the Earth. The dish had to be pointed directly at the satellite, with nothing blocking the signal. Weaker signals required larger dishes.[4][5][6]

The dishes worked by receiving a low-power C-Band (3.7–4.2 GHz)

feedhorn throat at the command of the receiver (commonly called a "polarotor" setup). Higher-end receivers did this transparently, switching polarization and moving the dish automatically as the user changed channels.[citation needed
]

By Spring of 1984, 18 C-Band satellites were in use for United States domestic communications, owned by five different companies.[7]

Satellite name Owner Orbital location

(degrees longitude)

Comstar 1 Comsat/AT&T 76
Comstar 2 76
Comstar 3 87
Comstar 4 127
Telstar 301 96
Galaxy 1 Hughes Communications 134
Galaxy 2 74
Satcom 1 RCA 139
Satcom 1R 139
Satcom 2 131
Satcom 2R 72
Satcom 3R 131
Satcom 4 84
Satcom 5 143
Westar 1 Western Union 79
Westar 3 91
Westar 4 99
Westar 5 123

The retail price for satellite receivers soon dropped, with some dishes costing as little as $2,000 by mid-1984.[4] Dishes pointing to one satellite were even cheaper.[8] Once a user paid for a dish, it was possible to receive even premium movie channels, raw feeds of news broadcasts or television stations from other areas. People in areas without local broadcast stations, and people in areas without cable television, could obtain good-quality reception with no monthly fees.[4][6] Two open questions existed about this practice: whether the Communications Act of 1934 applied as a case of "unauthorized reception" by TVRO consumers; and to what it extent it was legal for a service provider to encrypt their signals in an effort to prevent its reception.

The Cable Communications Policy Act of 1984 clarified all of these matters, making the following legal:[9][6][10]

  • Reception of unencrypted satellite signals by a consumer
  • Reception of encrypted satellite signals by a consumer, when they have received authorization to legally decrypt it

This created a framework for the wide deployment of encryption on analog satellite signals. It further created a framework (and implicit mandate to provide) subscription services to TVRO consumers to allow legal decryption of those signals. HBO and Cinemax became the first two services to announce intent to encrypt their satellite feeds late in 1984. Others were strongly considering doing so as well.[6] Where cable providers could compete with TVRO subscription options, it was thought this would provide sufficient incentive for competition.[11]

HBO and Cinemax began encrypting their west coast feeds services with

Request Television, and Viewer's Choice.[13] Channels scrambled (encrypted) with VideoCipher and VideoCipher II could be defeated, and there was a black market
for illegal descramblers.

By the end of 1987, 16 channels had employed encryption with another 7 planned in the first half of 1988. Packages that offered reduced rates for channels in bulk had begun to appear. At this time, the vast majority of analog satellite TV transponders still were not encrypted.[13] On November 1, 1988, NBC began scrambling its C-band signal but left its Ku band signal unencrypted in order for affiliates to not lose viewers who could not see their advertising. Most of the two million satellite dish users in the United States still used C-band. ABC and CBS were considering scrambling, though CBS was reluctant due to the number of people unable to receive local network affiliates.[14]

The growth of dishes receiving Ku band signals in North America was limited by the

Challenger disaster, since 75 satellites were to be launched prior to the suspension of the Space Shuttle program. Only seven Ku band satellites were in use.[15]

In addition to encryption,

HEMT, in noise reduction at microwave frequencies have also had an effect. However, a consequence of the higher frequency used for DBS services is rain fade
where viewers lose signal during a heavy downpour. C-band's immunity to rain fade is one of the major reasons the system is still used as the preferred method for television broadcasters to distribute their signal.

Popularity

TVRO systems were most popular in

restrictive covenants usually still prohibit this size of dish, except where such restrictions are illegal.[16] Support for systems dried up when strong encryption
was introduced around 1994. Many long-disconnected dishes still occupy their original spots.

TVRO on ships

The term TVRO has been in use on ships since it was introduced in the 1980s. One early provider of equipment was SeaTel with its first generation of stabilized satellite antennas that was launched in 1985, the TV-at-Sea 8885 system. Until this time ships had not been able to receive television signals from satellites due to their rocking motion rendering reception impossible. The SeaTel antenna however was stabilized using electrically driven gyroscopes and thus made it possible to point to the satellite accurately enough, that is to within 2°, in order to receive a signal. The successful implementation of stabilised TVRO systems on ships immediately led to the development of maritime

VSAT
systems. The second generation of SeaTel TVRO systems came in 1994 and was the 2494 antenna, which got its gyro signal from the ship rather than its own gyros, improving accuracy and reducing maintenance.

As of 2010, SeaTel continues to dominate the market for stabilized TVRO systems and has according to the Comsys group, a market share of 75%. Other established providers of stabilised satellite antennas are Intellian, KNS, Orbit, EPAK and KVH.

Current uses

Most of the free analogue channels that BUDs were built to receive have been taken offline.[citation needed] Due to the number of systems in existence, their lack of usefulness, and because many people consider them an eyesore, used BUDs can be purchased for very little money.[citation needed] As of 2009, there are 23 C-band satellites and 38 Ku/Ka band satellites.[17]

There were over 150 channels for people who want to receive subscription channels on a C-band dish via Motorola's 4DTV equipment via two vendors Satellite Receivers Ltd (SRL) and Skyvision. The 4DTV subscription system shutdown on August 16, 2016.

The dishes themselves can be modified to receive

DBS signals. Several companies market LNBs, LNBFs, and adaptor collars for big-dish systems. For receiving FTA signals the replacement should be capable of dual C/Ku reception with linear polarization, for DBS it will need a high band Ku LNBF using circular polarization. Older mesh dishes with perforations larger than 5mm are inefficient at Ku frequencies, because the smaller wavelengths
will pass through them. Solid fiberglass dishes usually contain metal mesh with large-diameter perforations as a reflector and are usually unsuitable for anything other than C band.

Large dishes have higher

television network with which a station is affiliated, without interruption due to inclement weather. BUDs are also still useful for picking-up weak signals at the edge of a satellite's broadcast "footprint" – the area at which a particular satellite is aimed. For this reason, BUDs are helpful in places like Alaska, or parts of the Caribbean
.

Modern equivalents

Large parabolic antennas similar to BUDs are still in production. New dishes differ in their construction and materials. New mesh dishes have much smaller perforations and solid dishes are now made with steel instead of fiberglass. New systems usually include a universal LNB that is switched electronically between horizontal and vertical polarization, obviating the need for a failure-prone polar rotor. As a complete system they have a much lower noise temperature than old BUDs, and are generally better for digital Ku reception. The prices of these dishes have fallen dramatically since the first BUDs were produced for several thousand dollars to as little as $200 for an 8 ft mesh started BUD sold on eBay or amazon as of 2014.[18] Typical uses for these systems include receiving free-to-air and subscription services.

See also

References

  1. ^ The "Glory Days" of Satellite Archived March 3, 2014, at the Wayback Machine
  2. ^ Giarrusso, Michael (July 28, 1996). "Tiny Satellite Dishes Sprout in Rural Areas". Los Angeles Times. Retrieved July 1, 2014.
  3. ^ Keating, Stephen (1999). "Stealing Free TV, Part 2". The Denver Post. Retrieved July 3, 2014.
  4. ^
    Knight-Ridder News Service
    . p. 1C.
  5. ^ Reibstein, Larry (September 27, 1981). "Watching TV Via Satellite Is Their Dish". The Philadelphia Inquirer. p. E01.
  6. ^
    Akron Beacon-Journal
    . p. F-1.
  7. ^ "Where the Birds Are" (PDF). Broadcasting. April 9, 1984. p. 48. Retrieved June 9, 2015.
  8. Wichita Eagle
    . Knight-Ridder News Service. p. 6C.
  9. ^ Goldwater, Barry (October 30, 1984). "S.66 - 98th Congress (1983-1984): Cable Communications Policy Act of 1984". www.congress.gov. Retrieved September 22, 2020.
  10. ^
    Knight-Ridder Newspapers
    . Retrieved April 10, 2014.
  11. ^ Wolf, Ron (January 20, 1985). "Direct-Broadcast TV Is Still Not Turned On". The Philadelphia Inquirer. p. C01.
  12. ^ "CNN shuts out dish owners". The Dispatch. July 1, 1986. p. 10. Retrieved September 22, 2020.
  13. ^ a b "Scrambling Information: 1988". National Cable Television Association. February 5, 1988.
  14. ^ "Scrambled NBC Bad News for Satellite Pirates". San Francisco Chronicle. United Press International. November 3, 1988. p. E3.
  15. ^ Nye, Doug (February 4, 1988). "Newest Technology Could Become a Major Threat to Local Cable Firms". The State. Columbia, South Carolina.
  16. ^ "Installing Consumer-Owned Antennas and Satellite Dishes". FCC. Retrieved November 21, 2008.
  17. ^ "SatelliteGuys.US - TheList". December 15, 2009. Archived from the original on December 15, 2009. Retrieved January 23, 2023.
  18. ^ 6.5' Fortec Star with Polar Mount

External links

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