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A cable converter box or television converter box is an electronic tuning device that transposes/converts channels from a cable television service to an analog RF signal on a single channel, usually VHF channel 3 or 4, or to a different output for digital televisions such as HDMI.
The device allows a television set that is not "cable ready" to receive cable channels. While later televisions were "cable ready" with a standard converter built-in, the existence of premium television (aka pay per view) and the advent of digital cable have continued the need for various forms of these devices for cable television reception. While not an explicit part of signal conversion, many cable converter boxes include forms of descrambling to manage carrier-controlled access restriction to various channels.
Cable-ready televisions and other cable-aware A/V devices such as video recorders can similarly convert cable channels to a regular television set, but these do not include advanced capabilities such as descrambling or digital downconversion.
The task of a cable box is to convert a television channel from those transmitted over the CATV wire.
The basic converter box is passive and does not communicate back to the carrier. It simply tunes to one of the channels being transmitted together over the wire and re-transmits it to a television or other video device on a standard broadcast frequency (usually a customer-selected, locally unused frequency between VHF 2 and 4). Like other set-top boxes, converter boxes usually provide multiple options for the output channel (either 2/3 or 3/4) so that the same box can be used, with simple configuration, in multiple television markets. Despite not having a broadcast reception television antenna, a strong local television station can cause interference with the TV's reception of the cable converter's signal, resulting in undesired static or ghosting.
Later cable boxes became addressable, allowing the carrier to independently identify one cable box from another. In early systems, this permitted the carrier to send instructions to the boxes by addressing them over the wire. This allowed customers to subscribe to premium television and pay-per-view. More recent cable boxes, particularly those for digital cable, engage in two-way communication with the carrier central office, allowing for more advanced and interactive features.
Typically, a cable converter box has two coaxial F-type female connectors; one "Cable In" for a coaxial cable from the wall jack (containing the CATV signal), one "TV Out" connected to the television where an antenna or other RF device (such as a VCR) would be connected. Newer cable boxes also tend to come standard with an IEEE 1394 interface (aka "FireWire") [1] and RCA jacks for composite video and stereo audio. More advanced analog video devices may have S-video and/or HDMI outputs to support HDTV.
In early days, before televisions came standard with 75Ω coaxial antenna connectors, cable boxes came with adapters that would allow the coaxial cable to connect to the 300Ω twin lead screws used with traditional antennas.
Major manufacturers of cable boxes have included Jerrold Electronics, General Instrument (which Jerrold merged into), Cisco (which Scientific Atlanta merged into), and Motorola (which General Instruments merged into).
An addressable cable box is one that can be controlled by the local cable company. Addressability is the process by which (optionally encrypted) messages are sent from the cable provider for a particular cable box via the cable signal. The cable company can "address" a particular customer's cable box to command it to activate or deactivate the descrambling of selected premium or pay-per view channels. The system can also send messages. This function affords the cable company the ability to add or delete descrambling on the channels that come in through the coaxial cable line. It also allows them to remotely disable the box, for reasons such as non-payment of the cable bill or theft of the unit itself. Such commands are referred to as bullets and are a transmitted message which affects the cable box program effectively disabling or "killing" it. "Bullets" do not affect the electronics inside converters or descramblers, only the programming. Non-addressable boxes are "bulletproof", as they are unable to detect such messages.
A descrambler is a device that unscrambles the encoded signal and restores the picture and sound of a scrambled channel.
Typical modern cable boxes include some form of descrambling ability. Such a cable box must also be addressable (see below) in order to be told to descramble the signal for a given channel. Early electronic cable boxes, for example, could descramble channels that used signal inversion as a scrambling method.
In many markets, carriers provided devices with simple or no descrambling capability, although the carrier may use different forms of scrambling for different premium channels. Certain premium channels or services could require an upgrade to a more advanced converter box that was capable of the necessary descrambling method. This is less true in the era of digital cable and cheap consumer electronics.
When a descrambler is included in a cable converter box, it is sometimes referred to as a converter/descrambler, or combination unit.
Digital cable is a method of delivering cable television as digital data instead of analog frequency. Many modern cable systems provide digital cable for at least part of their channel lineup.
Because many carriers continue to use analog transmission for legacy and low-numbered channels, and digital transmission for higher channels, a typical digital cable box is also able to convert traditional analog cable signals.
Digital television allows higher quality and quantity of cable TV signals. Digital transmission is compressed and allows a much greater capacity than analog signals; it almost eliminates interference, which has always been a hindrance to the cable TV industry. Digital converters have the same purpose as analog ones but are able to receive digital cable signals. With more data than analog in the same bandwidth, the system delivers superior picture and sound quality.
Despite the advance of cable-ready television sets, most users will need a cable box to receive digital channels. However, customers who do not subscribe to any digital channels can go without; many carriers provide "basic cable" service within the analog range, avoiding the need for distributing a box. However, advanced carrier services such as pay per view and video on demand will require a box.
CableCARD technology allows a third-party digital converter device to connect to and receive signals from a digital cable provider, instead of being reliant on a box provided by the cable provider.
AllVid was a CableCARD replacement proposed by the FCC, intended to provide bidirectional compatibilities such as interactive programming guides, video-on-demand and pay-per-view, since retail CableCARD-ready devices are unable to access such systems. [2] [3] [4]
Modern cable boxes are digital and not only addressable but can also perform two-way communication between the box and the provider. In addition, they include built-in programming guide and schedule information, in addition to weather, messaging, and on-demand services.
Some carriers have made available combination DVR/cable box devices, which include all the features of a modern digital cable converter box with the ability to record shows. These are intended to compete with stand-alone DVRs such as TiVo, although the cable provider can exert far more control over the operation of the combination units, leading to undesirable provider-mandated restrictions on the recordability and replayability of programs.
Amateur television (ham TV) operators use the frequencies corresponding to Cable channels 57-60 hooked up to outdoor UHF antennas.
Analog cable-ready televisions and other cable-capable devices (such as VCRs) eliminated many, but not all, applications where cable boxes were needed. Digital cable, however, made cable boxes more of a necessity as it provided channels that cable-ready televisions could not.
CableCARD technology allows a third-party digital converter device to connect to and receive signals from a digital cable provider, instead of being reliant on a box provided by the cable provider. This technology is being integrated into other devices such as DVRs and even personal computers, allowing them to take over all the capabilities of a carrier-provided cable converter box. However, carriers have been slow to distribute and fully support CableCARD technology.
AllVid is a CableCARD replacement proposed by the FCC, intended to provide bidirectional compatibilities such as interactive programming guides, video-on-demand and pay-per-view, since retail CableCARD-ready devices are unable to access such systems. [2]
Cable-ready television sets have coaxial cable F connectors. One end connects to the cable, antenna, or VHF jack on the back of the television set; the other end connects to the wall CATV outlet. Once the television is connected through the cable to the wall CATV outlet, the television will need to be programmed to receive the cable channels. The instruction manual that came with the television should have instructions on how to program cable channels.
Non-cable-ready television sets are older televisions (e.g., with a rotary knob) with no coaxial cable F connector; a cable converter box or a cable-ready VCR is necessary to receive cable.
After ending the analogue CATV transmissions, an (analogue) cable-ready TV or VCR is no longer be able to tune cable channels directly. A customer needs to install a digital cable box or a digital television adapter (which is a very basic kind of digital cable box). Newer TVs, however, often feature digital tuners including digital cable tuners (QAM for USA, DVB-C for Europe). But cable providers often encrypt all of most of the channels, causing the TV to be unable to receive these channels directly. In USA, there were TVs with CableCARD slot to allow decryption without a cable box. However, they are now gone. But there are other devices like TiVo that can accept a CableCARD and decrypt channels the customer subscribes to without need of a cable box.
Basic cable service is the least expensive cable service provided by cable companies to their customers. This service usually includes local TV channels.
Premium cable service includes additional programming service provided by the cable company to subscribing customers. The extra fee for such additional service may be per channel, per group of channels, or based on any other combination of channels.
With pay-per-view services, selected channels offer movies and special events such as sports or adult entertainment, for an additional fee, on a per-movie or per-program basis. A special addressable converter is furnished by the cable company to subscribers of this service. Through the use of special equipment, the cable company can direct the customer's cable box to descramble the program for which the fee was paid.
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Cable television is a system of delivering television programming to consumers via radio frequency (RF) signals transmitted through coaxial cables, or in more recent systems, light pulses through fibre-optic cables. This contrasts with broadcast television, in which the television signal is transmitted over-the-air by radio waves and received by a television antenna, or satellite television, in which the television signal is transmitted over-the-air by radio waves from a communications satellite and received by a satellite dish on the roof. FM radio programming, high-speed Internet, telephone services, and similar non-television services may also be provided through these cables. Analog television was standard in the 20th century, but since the 2000s, cable systems have been upgraded to digital cable operation.
A set-top box (STB), also known as a cable box, receiver, or simply box, and historically television decoder or a converter, is an information appliance device that generally contains a TV tuner input and displays output to a television set, turning the source signal into content in a form that can then be displayed on the television screen or other display device. It is designed to be placed alongside or "on top" of a television set.
In telecommunications, a scrambler is a device that transposes or inverts signals or otherwise encodes a message at the sender's side to make the message unintelligible at a receiver not equipped with an appropriately set descrambling device. Whereas encryption usually refers to operations carried out in the digital domain, scrambling usually refers to operations carried out in the analog domain. Scrambling is accomplished by the addition of components to the original signal or the changing of some important component of the original signal in order to make extraction of the original signal difficult. Examples of the latter might include removing or changing vertical or horizontal sync pulses in television signals; televisions will not be able to display a picture from such a signal. Some modern scramblers are actually encryption devices, the name remaining due to the similarities in use, as opposed to internal operation.
A cable modem is a type of network bridge that provides bi-directional data communication via radio frequency channels on a hybrid fiber-coaxial (HFC), radio frequency over glass (RFoG) and coaxial cable infrastructure. Cable modems are primarily used to deliver broadband Internet access in the form of cable Internet, taking advantage of the high bandwidth of a HFC and RFoG network. They are commonly deployed in the Americas, Asia, Australia, and Europe.
An RF modulator is an electronic device used to convert signals from devices such as media players, VCRs and game consoles to a format that can be handled by a device designed to receive a modulated RF input, such as a radio or television receiver. Its input is a baseband signal, which is used to modulate a radio frequency source.
Digital cable is the distribution of cable television using digital data and video compression. The technology was first developed by General Instrument. By 2000, most cable companies offered digital features, eventually replacing their previous analog-based cable by the mid 2010s. During the late 2000s, broadcast television converted to the digital HDTV standard, which was incompatible with existing analog cable systems.
A cable television headend is a master facility for receiving television signals for processing and distribution over a cable television system. A headend facility may be staffed or unstaffed and is typically surrounded by some type of security fencing. The building is typically sturdy and purpose-built to provide security, cooling, and easy access for the electronic equipment used to receive and re-transmit video over the local cable infrastructure. One can also find head ends in power-line communication (PLC) substations and Internet communications networks.
Hybrid fiber-coaxial (HFC) is a broadband telecommunications network that combines optical fiber and coaxial cable. It has been commonly employed globally by cable television operators since the early 1990s.
Television encryption, often referred to as scrambling, is encryption used to control access to pay television services, usually cable, satellite, or Internet Protocol television (IPTV) services.
Cable-ready is a designation which indicates that a TV set or other television-receiving device is capable of receiving cable TV without a set-top box.
Cable television first became available in the United States in 1948. By 1989, 53 million U.S. households received cable television subscriptions, with 60 percent of all U.S. households doing so in 1992. Most cable viewers in the U.S. reside in the suburbs and tend to be middle class; cable television is less common in low income, urban, and rural areas.
Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location. The signals are received via an outdoor parabolic antenna commonly referred to as a satellite dish and a low-noise block downconverter.
A digital television adapter (DTA), commonly known as a converter box or decoder box, is a television tuner that receives a digital television (DTV) transmission, and converts the digital signal into an analog signal that can be received and displayed on an analog television set. Some also have an HDMI output since some TVs with HDMI do not have a digital tuner. The input digital signal may be over-the-air terrestrial television signals received by a television antenna, or signals from a digital cable system. It normally does not refer to satellite TV, which has always required a set-top box either to operate the big satellite dish, or to be the integrated receiver/decoder (IRD) in the case of direct-broadcast satellites (DBS).
A coupon-eligible converter box (CECB) was a digital television adapter that met eligibility specifications for subsidy "coupons" from the United States government. The subsidy program was enacted to provide terrestrial television viewers with an affordable way to continue receiving free digital terrestrial television services after the nation's television service transitioned to digital transmission and analog transmissions ceased. The specification was developed by the National Telecommunications and Information Administration (NTIA), with input from the broadcast and consumer electronics industries as well as public interest groups.
TrueVisions is the largest provider of a cable analog television (CAtv) and digital satellite television (DStv) in Thailand. TrueVisions is a subsidiary of the business division of True Corporation.
Cable television piracy is the act of obtaining unauthorized access to cable television services. It is a form of copyright infringement and a federal crime. Reception of cable television without authorization by a cable operator is forbidden by both federal and state laws. In Missouri, cable television piracy is usually a class A misdemeanor; if the service is $500 or more, it is classified as a class C felony.
Addressability is the ability of a digital device to individually respond to a message sent to many similar devices. Examples include pagers, mobile phones and set-top boxes for pay TV. Computer networks are also addressable via the MAC address on Ethernet network cards, and similar networking protocols like Bluetooth. This allows data to be sent in cases where it is impractical to control exactly where or to which devices the message is physically sent.
When a descrambler is added to the Cable Converter Box in the same chassis, it is referred to as a Converter/Descrambler or sometimes a Combination Unit, and is a type of Set-top box, it allows : local broadcast channels, basic cable channels, authorized premium channels, "Pay-Per-View" (PPV), and “Video On Demand” (VOD) services to be viewed. A Combination Converter/Descrambler is generally called a Set-top box or STB it is a single (one-piece) system installed in a single cabinet and represents a single component that is capable of descrambling premium services, like HBO or Showtime, pay-per-view cable channels., Video on Demand, Games or other specialty pay services, and transposes the cable signal for RF output on channel 3 or 4. This unit contains a converter and a descrambler, enclosed in a common box and outputs the signal directly to a TV, VCR, DVR, PC, DVD or video projector.
Analog passthrough is a feature found on some digital-to-analog television converter boxes. Boxes without the analog passthrough feature only allow older, analog-only TVs to view digital TV. Those with analog pass-through allow both digital and analog television to be viewed on older TVs.
Full Channel, Inc. was an American pay television and telecommunications provider set in Rhode Island. At the time of its acquisition by CountryWide Broadband it was the third-largest cable television and Internet service provider in the state. Its wired communications network was available to the approximately 50,000 residents of Bristol County, Rhode Island. Full Channel's main office was at 57 Everett Street in Warren, Rhode Island, U.S.