A set-top box (STB) or set-top unit (STU) is an information appliance device that generally contains a TV-tuner input and displays output to a television set and an external source of signal, turning the source signal into content in a form that then be displayed on the television screen or other display device. They are used in cable television, satellite television, and over-the-air television systems, as well as other uses.
In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction.
In communications and electronic engineering, an intermediate frequency (IF) is a frequency to which a carrier wave is shifted as an intermediate step in transmission or reception. The intermediate frequency is created by mixing the carrier signal with a local oscillator signal in a process called heterodyning, resulting in a signal at the difference or beat frequency. Intermediate frequencies are used in superheterodyne radio receivers, in which an incoming signal is shifted to an IF for amplification before final detection is done.
In telecommunications, frequency-division multiplexing (FDM) is a technique by which the total bandwidth available in a communication medium is divided into a series of non-overlapping frequency bands, each of which is used to carry a separate signal. This allows a single transmission medium such as a cable or optical fiber to be shared by multiple independent signals. Another use is to carry separate serial bits or segments of a higher rate signal in parallel.
Composite video is an analog video transmission that carries standard definition video typically at 480i or 576i resolution as a single channel. Video information is encoded on one channel, unlike the higher-quality S-video and the even higher-quality component video. In all of these video formats, audio is carried on a separate connection.
Public-access television is traditionally a form of non-commercial mass media where the general public can create content television programming which is narrowcast through cable TV specialty channels. Public-access television was created in the United States between 1969 and 1971 by the Federal Communications Commission (FCC), under Chairman Dean Burch, based on pioneering work and advocacy of George Stoney, Red Burns, and Sidney Dean.
Amateur television (ATV) is the transmission of broadcast quality video and audio over the wide range of frequencies of radio waves allocated for radio amateur (Ham) use. ATV is used for non-commercial experimentation, pleasure, and public service events. Ham TV stations were on the air in many cities before commercial television stations came on the air. Various transmission standards are used, these include the broadcast transmission standards of NTSC in North America and Japan, and PAL or SECAM elsewhere, utilizing the full refresh rates of those standards. ATV includes the study of building of such transmitters and receivers, and the study of radio propagation of signals travelling between transmitting and receiving stations.
In cable television, governments apply a must-carry regulation stating that locally licensed television stations must be carried on a cable provider's system.
The Children's Internet Protection Act (CIPA) requires that K–12 schools and libraries in the United States use Internet filters and implement other measures to protect children from harmful online content as a condition for federal funding. It was signed into law on December 21, 2000, and was found to be constitutional by the United States Supreme Court on June 23, 2003.
Dot crawl is the popular name for a visual defect of color analog video standards when signals are transmitted as composite video, as in terrestrial broadcast television. It consists of animated checkerboard patterns which appear along horizontal color transitions. It results from intermodulation or crosstalk between chrominance and luminance components of the signal, which are imperfectly multiplexed in the frequency domain.
Television encryption, often referred to as "scrambling", is encryption used to control access to pay television services, usually cable or satellite television services.
United States v. Playboy Entertainment Group, 529 U.S. 803 (2000), is a United States Supreme Court case in which the Court struck down Section 505 of the Telecommunications Act of 1996, which required that cable television operators completely scramble or block channels that are "primarily dedicated to sexually-oriented programming" from 10 pm to 6 am.
Ashcroft v. American Civil Liberties Union, 535 U.S. 564 (2002), was a 2002 United States Supreme Court case involving the American Civil Liberties Union and the United States government regarding the Child Online Protection Act (COPA). The unconstitutionality of the law was ultimately upheld by the United States Court of Appeals for the Third Circuit, while earlier injunctions against the law by that same court were at first dismissed by but later upheld by the Supreme Court. Ashcroft v. Free Speech Coalition (2002) dealt with a similar law, the Child Pornography Prevention Act of 1996 (CPPA).
Cable television first became available in the United States in 1948, with subscription services following in 1949. Data by SNL Kagan shows that as of 2006 about 58.4% of all American homes subscribe to basic cable television services. 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.
According to research done by the Organisation for Economic Co-operation and Development (OECD) the Netherlands is ranked with Switzerland in having the most broadband subscriptions per 100 inhabitants, has no bandwidth caps, and has the most homes passed in Europe in terms of connection speeds of 50 Mbit/s and higher.
United States v. American Library Association, 539 U.S. 194 (2003), was a decision in which the United States Supreme Court ruled that the United States Congress has the authority to require public schools and libraries receiving E-Rate discounts to install web filtering software as a condition of receiving federal funding. In a plurality opinion, the Supreme Court ruled that: 1.) public libraries' use of Internet filtering software does not violate their patrons' First Amendment free speech rights; 2.) The Children's Internet Protection Act is not unconstitutional.
Cartoon Network Latin America is a satellite and cable television channel distributed by AT&T for the Latin American audience and the Caribbean. It is the Latin American version of original Cartoon Network television channel in the United States. It is divided into six feeds, all originating from its central headquarters in Atlanta, Georgia, United States; four are in Spanish, one is in Portuguese (Brazil), and another feed aimed at the Caribbean is only in English. The feeds have different schedules.
In telecommunication, equalization is the reversal of distortion incurred by a signal transmitted through a channel. Equalizers are used to render the frequency response—for instance of a telephone line—flat from end-to-end. When a channel has been equalized the frequency domain attributes of the signal at the input are faithfully reproduced at the output. Telephones, DSL lines and television cables use equalizers to prepare data signals for transmission.
Aereo was a technology company based in New York City that allowed subscribers to view live and time-shifted streams of over-the-air television on Internet-connected devices. The service opened to customers in March 2012, and was backed by Barry Diller's IAC.
American Broadcasting Cos., Inc. v. Aereo, Inc., 573 U.S. ___ (2014), was a United States Supreme Court case. The Court ruled that the service provided by Aereo, allowing subscribers to view live and time-shifted streams of over-the-air television on Internet-connected devices, violated copyright laws.
