A set-top box (STB) or set-top assemblage (STU) is an advice apparatus accessory that about contains a tuner and connects to a television set and an alien antecedent of signal, axis the arresting into agreeable which is again displayed on the television awning or added affectation device. Set-top boxes are acclimated in cable television and accessory television systems, to transform the arresting from the cable or accessory to a anatomy that can be acclimated by the television set or added receiver. It additionally enhances the affection of arresting from cable or satellite
Saturday, 17 March 2012
History
Before the mid-1950s, all British television sets acquainted alone VHF Bandage I channels. Since all 5 Bandage I channels were active by BBC transmissions, ITV would accept to use Bandage III. This meant all the TV sets in the country would crave Bandage III converters which adapted the Bandage III arresting to a Bandage I signal. By 1955, back the aboriginal ITV stations started transmitting, around all fresh British Televisions had 13-channel tuners, bound authoritative Bandage III converters obsolete.
Before the All-Channel Receiver Act of 1962 appropriate US television receivers to be able to tune the absolute VHF and UHF ambit (which in North America was NTSC-M channels 2 through 83 on 54 to 890 MHz), a set-top box accepted as a UHF advocate would be installed at the receiver to about-face a allocation of the UHF-TV spectrum assimilate low-VHF channels for viewing. As some 1960s-era twelve-channel TV sets remained in use for abounding years, and Canada and Mexico were slower than the US to crave UHF tuners to be factory-installed in fresh TV's, a bazaar for these converters connected to abide for abundant of the 1970s.
Cable television represented a accessible another to deployment of UHF converters as broadcasts could be frequency-shifted to VHF channels at the cable head-end instead of the final examination location. Unfortunately, cable brought a fresh problem; best cable systems could not board the abounding 54-890 MHz VHF/UHF abundance ambit and the twelve channels of VHF amplitude were bound beat on best systems. Adding any added channels accordingly bare to be done by inserting the added signals into cable systems on non-standard frequencies, about either beneath VHF approach 7 (midband) or anon aloft VHF approach 13 (superband).
These frequencies corresponded to non-television casework (such as two-way radio) over-the-air and were accordingly not on accepted TV receivers. Before cable-ready TV sets became accepted in the backward 1980s, a set-top box accepted as a cable advocate box was bare to accept the added analog cable TV channels and catechumen them to analog video frequencies that could be apparent on a approved TV set. These boxes generally provided a active or wireless alien ascendancy which could be acclimated to about-face one called approach to a low-VHF abundance (most generally channels 3 or 4) for viewing. Block about-face of the absolute afflicted abundance bandage assimilate UHF, while beneath common, was acclimated by some models to accommodate abounding VCR affinity and the adeptness to drive assorted TV sets, admitting with a somewhat non-standard approach calculation scheme.
Newer television receivers abundantly bargain the charge for alien set-top boxes, although cable advocate boxes abide to be acclimated to descramble exceptional cable channels and to accept agenda cable channels, forth with application alternate casework like video on demand, pay per view, and home arcade through television. Satellite and microwave-based casework additionally crave specific alien receiver hardware, so the use of set-top boxes of assorted formats never absolutely disappeared.
Before the All-Channel Receiver Act of 1962 appropriate US television receivers to be able to tune the absolute VHF and UHF ambit (which in North America was NTSC-M channels 2 through 83 on 54 to 890 MHz), a set-top box accepted as a UHF advocate would be installed at the receiver to about-face a allocation of the UHF-TV spectrum assimilate low-VHF channels for viewing. As some 1960s-era twelve-channel TV sets remained in use for abounding years, and Canada and Mexico were slower than the US to crave UHF tuners to be factory-installed in fresh TV's, a bazaar for these converters connected to abide for abundant of the 1970s.
Cable television represented a accessible another to deployment of UHF converters as broadcasts could be frequency-shifted to VHF channels at the cable head-end instead of the final examination location. Unfortunately, cable brought a fresh problem; best cable systems could not board the abounding 54-890 MHz VHF/UHF abundance ambit and the twelve channels of VHF amplitude were bound beat on best systems. Adding any added channels accordingly bare to be done by inserting the added signals into cable systems on non-standard frequencies, about either beneath VHF approach 7 (midband) or anon aloft VHF approach 13 (superband).
These frequencies corresponded to non-television casework (such as two-way radio) over-the-air and were accordingly not on accepted TV receivers. Before cable-ready TV sets became accepted in the backward 1980s, a set-top box accepted as a cable advocate box was bare to accept the added analog cable TV channels and catechumen them to analog video frequencies that could be apparent on a approved TV set. These boxes generally provided a active or wireless alien ascendancy which could be acclimated to about-face one called approach to a low-VHF abundance (most generally channels 3 or 4) for viewing. Block about-face of the absolute afflicted abundance bandage assimilate UHF, while beneath common, was acclimated by some models to accommodate abounding VCR affinity and the adeptness to drive assorted TV sets, admitting with a somewhat non-standard approach calculation scheme.
Newer television receivers abundantly bargain the charge for alien set-top boxes, although cable advocate boxes abide to be acclimated to descramble exceptional cable channels and to accept agenda cable channels, forth with application alternate casework like video on demand, pay per view, and home arcade through television. Satellite and microwave-based casework additionally crave specific alien receiver hardware, so the use of set-top boxes of assorted formats never absolutely disappeared.
Cable converter box
A cable advocate box or television advocate box is blazon of set-top box that is an cyberbanking affability accessory that transposes/converts any of the accessible channels from a cable television account to an analog RF arresting on a distinct channel, usually VHF approach 3 or 4. The accessory allows a television set that is not “cable ready” to accept cable channels. While after televisions were "cable ready" with a accepted advocate built-in, the actuality of exceptional television (aka pay per view) and the appearance of agenda cable accept connected the charge for assorted forms of these accessories for cable television reception. While not an absolute allotment of arresting conversion, abounding cable advocate boxes accommodate forms of descrambling to administer carrier-controlled admission brake to assorted channels.
Digital television adapter
The alteration to earthbound agenda television afterwards the about-face of the millennium larboard abounding absolute television receivers clumsy to tune and affectation the fresh arresting directly. In the United States, area analog abeyance was completed in 2009 for full-service broadcasters, a federal subsidy was offered for coupon-eligible advocate boxes with deliberately-limited adequacy which would restore signals absent to agenda transition.
Professional set-top box
Professional set-top boxes are referred to as IRDs or chip receiver/decoders in the able advertisement audio/video industry. They are advised for added able-bodied acreage administration and arbor ascent environments, and are additionally technically superior, IRDs accept the audible affection of outputting uncompressed SDI signals, clashing customer STBs which don’t mostly because of absorb reasons
.
TV arresting sources
The arresting antecedent ability be an Ethernet cable, a accessory dish, a coaxial cable (see cable television), a blast band (including DSL connections), Broadband over Power Line, or alike an accustomed VHF or UHF antenna. Content, in this context, could beggarly any or all of video, audio, Internet web pages, alternate video games, or added possibilities.
Professional set-top box
Professional set-top boxes are referred to as IRDs or chip receiver/decoders in the able advertisement audio/video industry. They are advised for added able-bodied acreage administration and arbor ascent environments, and are additionally technically superior, IRDs accept the audible affection of outputting uncompressed SDI signals, clashing customer STBs which don’t mostly because of absorb reasons
.
TV arresting sources
The arresting antecedent ability be an Ethernet cable, a accessory dish, a coaxial cable (see cable television), a blast band (including DSL connections), Broadband over Power Line, or alike an accustomed VHF or UHF antenna. Content, in this context, could beggarly any or all of video, audio, Internet web pages, alternate video games, or added possibilities.
Hybrid
In the backward 2000s, there has been a cogent advance in the acceptance of amalgam IPTV set-top boxes in both the pay TV and free-to-air set-top box markets.citation needed A amalgam set-top box allows acceptable TV advertisement (from terrestrial, satellite, or cable providers) to be brought calm with video delivered over the Internet, and with claimed multimedia content. This enables television admirers to admission a greater array of agreeable on their TV sets, after defective a abstracted box for anniversary service.
Hybrid IPTV set-top boxes additionally accredit admirers to admission a ambit of avant-garde alternate services, such as VOD and time-shifting TV, as able-bodied as Internet applications, including video telephony, surveillance, gaming, shopping, e-government accessed via a television set.
From a pay-TV operator’s perspective, a amalgam IPTV set-top box gives them greater abiding adaptability by enabling them to arrange a advanced array fresh casework and applications as and back consumers require, best generally after the charge to advancement accessories or for an architect to appointment and reconfigure or bandy out the device. This minimises the amount of ablution fresh services, increases acceleration to bazaar and banned disruption for consumers.1
One aggregation in the amalgam IPTV set-top box bazaar is Avant-garde Agenda Advertisement (ADB), which launched its aboriginal amalgam agenda earthbound (DTT) /IPTV set-top box in 20052 that provided Telefónica with the agenda TV belvedere for its Imagenio account at the end of that year.3 In 2009, the aggregation additionally provided Europe’s aboriginal three-way amalgam agenda TV belvedere to Polish agenda accessory abettor n that enables its subscribers to appearance agreeable delivered via satellite, agenda terrestrial, and IP networks.4
Hybrid IPTV set-top boxes additionally accredit admirers to admission a ambit of avant-garde alternate services, such as VOD and time-shifting TV, as able-bodied as Internet applications, including video telephony, surveillance, gaming, shopping, e-government accessed via a television set.
From a pay-TV operator’s perspective, a amalgam IPTV set-top box gives them greater abiding adaptability by enabling them to arrange a advanced array fresh casework and applications as and back consumers require, best generally after the charge to advancement accessories or for an architect to appointment and reconfigure or bandy out the device. This minimises the amount of ablution fresh services, increases acceleration to bazaar and banned disruption for consumers.1
One aggregation in the amalgam IPTV set-top box bazaar is Avant-garde Agenda Advertisement (ADB), which launched its aboriginal amalgam agenda earthbound (DTT) /IPTV set-top box in 20052 that provided Telefónica with the agenda TV belvedere for its Imagenio account at the end of that year.3 In 2009, the aggregation additionally provided Europe’s aboriginal three-way amalgam agenda TV belvedere to Polish agenda accessory abettor n that enables its subscribers to appearance agreeable delivered via satellite, agenda terrestrial, and IP networks.4
IPTV
In IPTV networks, the set-top box is a baby computer accouterment two-way communications on an IP arrangement and adaptation the video alive media. IP set-top boxes accept a congenital in home arrangement interface which can be Ethernet or one of the absolute wire home networking technologies such as HomePNA or the ITU-T G.hn standard, which provides a way to actualize a accelerated (up to 1 Gigabit/s) bounded breadth arrangement application absolute home base (power lines, buzz lines, and coaxial cables).5
In the US and Europe, blast companies use IPTV (often on ADSL or optical cilia networks) as a agency to attempt with acceptable bounded cable television monopolies.
In the US and Europe, blast companies use IPTV (often on ADSL or optical cilia networks) as a agency to attempt with acceptable bounded cable television monopolies.
Ambiguities in the definition
With the appearance of flat-panel televisions, set-top boxes are now added in contour than the acme of best avant-garde TV sets. Because of this, set-top boxes are generally placed below televisions, and the appellation set-top box has become article of a misnomer, possibly allowance the acceptance of the appellation digibox. Additionally, newer set-top boxes that sit at the bend of IP based administration networks are generally alleged Net-Top-Boxes or NTBs. This is to differentiate amid accessories with IP or RF inputs.
In Europe, a set-top box does not necessarily accommodate a tuner of its own. A box affiliated to a television (or VCR) set's SCART adapter is fed with the baseband television arresting from the set's tuner, and can ask the television to affectation the alternate candy arresting instead.
This SCART affection had been acclimated for affiliation to alternation adaptation accessories by pay TV operators in Europe, and in the accomplished was acclimated for affiliation to teletext accessories afore the decoders became built-in. The approachable arresting could be of the aforementioned attributes as the admission signal, or RGB basal video, or alike an "insert" over the aboriginal signal, acknowledgment to the "fast switching" affection of SCART.
In case of alternation pay-TV, this access abhorred the charge for a additional alien control. The use of agenda television signals in added avant-garde pay-TV schemes requires that adaptation booty abode afore the digital-to-analogue about-face step, apprehension the video outputs of an alternation SCART adapter no best acceptable for alternation to decryption hardware. Standards such as DVB's Common Interface and ATSC's CableCARD accordingly use a PCMCIA-like agenda amid as allotment of the agenda arresting aisle as their another to a tuner-equipped set-top box.
The acumen amid alien tuner or demodulator boxes (traditionally advised to be "set-top boxes") and accumulator accessories (such as VCR, DVD, or disc-based PVR units) is additionally blurred by the accretion deployment of accessory and cable tuner boxes with adamantine discs, arrangement or USB interfaces built-in
Devices with computer terminal-like capabilities, such as the WebTV attenuate client, additionally abatement into the blah breadth that could be catered for by the appellation NTB
.
Set-top boxes were additionally fabricated to accredit bankrupt captioning on earlier sets in North America, afore this became a allowable admittance in fresh TV sets. Some accept additionally been produced to aphasiac the audio (or alter it with noise) back profanity is detected in the captioning, area the abhorrent chat is additionally blocked. Some additionally accommodate a V-chip that allows alone programmes of some television agreeable ratings. A action that banned children's time watching TV or arena video amateur may additionally be congenital in, admitting some of these assignment on the mains electricity rather than the video signal
.
Software quality
As complication of the set-top box increases, thecomputer application affection practices of the industry become accessible and abounding systems accept bugs.6 However, users of software-based solutions such as Windows Vista's Media Center, MythTV and Select-TV accept a actual adjustable account of accessible appearance alignment from basal Agenda video recorder (DVR)-like functionality to appearance such as DVD copying, home automation, and house-wide music/video book playing
.
nergy use
In 2011, set-top boxes accustomed absorption for their activity consumption. The boilerplate set-top box agreement (one HD-DVR and one HD cable box) uses 446 kWh per year—more than a fresh 21 cubic bottom Activity Star refrigerator, which uses 415 kWh a year.7 Currently, there are no federal apparatus standardsclarification needed in abode to adapt the activity ability of set-top boxes, admitting in June 2011 the U.S. Department of Activity appear affairs to accommodate them in approaching regulations.8
In Europe, a set-top box does not necessarily accommodate a tuner of its own. A box affiliated to a television (or VCR) set's SCART adapter is fed with the baseband television arresting from the set's tuner, and can ask the television to affectation the alternate candy arresting instead.
This SCART affection had been acclimated for affiliation to alternation adaptation accessories by pay TV operators in Europe, and in the accomplished was acclimated for affiliation to teletext accessories afore the decoders became built-in. The approachable arresting could be of the aforementioned attributes as the admission signal, or RGB basal video, or alike an "insert" over the aboriginal signal, acknowledgment to the "fast switching" affection of SCART.
In case of alternation pay-TV, this access abhorred the charge for a additional alien control. The use of agenda television signals in added avant-garde pay-TV schemes requires that adaptation booty abode afore the digital-to-analogue about-face step, apprehension the video outputs of an alternation SCART adapter no best acceptable for alternation to decryption hardware. Standards such as DVB's Common Interface and ATSC's CableCARD accordingly use a PCMCIA-like agenda amid as allotment of the agenda arresting aisle as their another to a tuner-equipped set-top box.
The acumen amid alien tuner or demodulator boxes (traditionally advised to be "set-top boxes") and accumulator accessories (such as VCR, DVD, or disc-based PVR units) is additionally blurred by the accretion deployment of accessory and cable tuner boxes with adamantine discs, arrangement or USB interfaces built-in
Devices with computer terminal-like capabilities, such as the WebTV attenuate client, additionally abatement into the blah breadth that could be catered for by the appellation NTB
.
Set-top boxes were additionally fabricated to accredit bankrupt captioning on earlier sets in North America, afore this became a allowable admittance in fresh TV sets. Some accept additionally been produced to aphasiac the audio (or alter it with noise) back profanity is detected in the captioning, area the abhorrent chat is additionally blocked. Some additionally accommodate a V-chip that allows alone programmes of some television agreeable ratings. A action that banned children's time watching TV or arena video amateur may additionally be congenital in, admitting some of these assignment on the mains electricity rather than the video signal
.
Software quality
As complication of the set-top box increases, thecomputer application affection practices of the industry become accessible and abounding systems accept bugs.6 However, users of software-based solutions such as Windows Vista's Media Center, MythTV and Select-TV accept a actual adjustable account of accessible appearance alignment from basal Agenda video recorder (DVR)-like functionality to appearance such as DVD copying, home automation, and house-wide music/video book playing
.
nergy use
In 2011, set-top boxes accustomed absorption for their activity consumption. The boilerplate set-top box agreement (one HD-DVR and one HD cable box) uses 446 kWh per year—more than a fresh 21 cubic bottom Activity Star refrigerator, which uses 415 kWh a year.7 Currently, there are no federal apparatus standardsclarification needed in abode to adapt the activity ability of set-top boxes, admitting in June 2011 the U.S. Department of Activity appear affairs to accommodate them in approaching regulations.8
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