Television broadcaster

A television broadcaster, or television network, is a telecommunications network used to distribute television content. It functions through a central operation that provides programming to many different television stations. These stations may be local affiliates, pay television providers, or multichannel video programming distributors. In many countries, a central hub sends identical content to all its stations. In these cases, individual transmitters often act as large repeater stations. This allows a single signal to reach millions of households across vast distances.

The mechanism of a network relies on a process called the network feed. First, a central operation creates the video and audio signals. The network then sends this signal to many local affiliated television stations. Depending on the size of the network, this signal might go to 200 or more stations. It could also be as few as a dozen or fewer. These local stations receive the feed and broadcast it to viewers in their specific area. Local stations often have the ability to interrupt the network feed. They might do this to insert local commercials, station identifications, or emergency alerts. Some stations use regional variation to break away from the network for their own local programming.

Television networks can be categorized by how they operate and how they are funded. Some networks produce all of their own programming. Others rely on production companies like Warner Bros. Television or Sony Pictures Television to distribute content. Some networks also import programs from other countries or use archived shows. In North America, many networks are branded as "channels" because they are singular operations. They do not have affiliates or component stations. Instead, they are distributed via cable or direct-broadcast satellite providers. These are often called cable networks or specialty channels. There are also non-commercial networks, such as the Public Broadcasting Service (PBS) in the United States. PBS is a non-profit, publicly owned educational service where member stations have significant freedom to schedule shows.

The history of television is deeply connected to the evolution of radio. Many early networks, such as the BBC, CBC, and NBC, evolved from earlier radio networks. In the United States, radio stations began limited operations in the 1910s. A major milestone occurred in November 1920 when KDKA in Pittsburgh became the world's first commercially licensed radio station. As interest in moving pictures grew, researchers applied radio technology to television. Electronic television was demonstrated in San Francisco on September 7, 1927. This system was designed by Philo Taylor Farnsworth, who had worked on it since 1920.

To transmit the large amount of information required for television, new technology was needed. A radio signal is much smaller than an electronic television signal. Early researchers considered using radio relay towers, but this was extremely expensive. In 1929, Bell Telephone Laboratories patented coaxial cable. This cable was originally an improvement for telephone devices. However, its high capacity made it ideal for long-distance television transmission. It could handle a frequency band of 1 MHz. Germany demonstrated this application in 1936 by relaying televised telephone calls between Berlin and Leipzig using cable.

The scale of television networks is massive. In the United States, the "Big Three" networks—ABC, CBS, and NBC—long dominated the industry. In October 1986, the Fox Broadcasting Company launched and joined them as part of the "Big Four." Some networks provide much less programming than others. For example, The CW provides only fifteen hours of primetime programming each week. MyNetworkTV provides only ten hours of primetime programming per week. The financial scale is also significant. Cable and satellite providers pay networks a set rate per subscriber. For example, providers pay more than $5.00 per subscriber to ESPN.

Modern network operations rely on advanced technology to maintain quality. Most operations centers use broadcast automation to handle various tasks. This includes managing programming and video server playout. To ensure everything stays seamless, these systems use exact atomic time. They get this time from Global Positioning Systems (GPS) or other sources. This synchronization allows the programming to appear perfect to viewers. This high level of technical coordination connects different systems across the entire broadcasting chain.