Broadcasting

Broadcasting is a way to share audio and audiovisual content with many people at once using electronic methods, usually through radio waves. It started with AM radio, which became popular around 1920 when people began using vacuum tube radio transmitters and receivers. Before that, most electronic communication, like early radio, telephone, and telegraph, was meant for just one person.

The word "broadcasting" comes from farming, where seeds are scattered widely. It was later used to describe spreading information through printed materials or the telegraph. By 1898, people began using it to talk about radio stations sending programs to many listeners.

Today, broadcasting usually means sending out radio and television programs over the air, but it can also happen through cables, like cable television. Anyone with a radio or TV can pick up these signals. Broadcasting includes both public services, like public and community radio and television, and private commercial radio and television. In many places, stations need a special permit called a broadcasting license to send out programs over the air. With the rise of digital technology in the 2000s, streaming services have also been called a form of broadcasting.

History

Main article: History of broadcasting

In 1894, an inventor named Guglielmo Marconi started working on sending messages without wires using something called radio waves. Soon after, in 1901, he showed that these waves could travel across the Atlantic Ocean. This was the beginning of sending messages by radio.

Audio radio broadcasting started in the early 1900s. After World War I, radio became popular for sharing news and entertainment. Television started in the 1920s with moving pictures shown by John Logie Baird. After World War II, television became common in homes. In the 2000s, broadcasting changed from old-style signals to digital signals, making the pictures and sound clearer.

Methods

In broadcasting, a powerful broadcast tower sends out high-frequency electromagnetic waves. These waves carry audio or video signals. Receivers, like radios or televisions, are tuned to pick up these waves and convert them back into the original content.

Historically, several methods have been used to share audio and video with many people. Early methods included telephone broadcasting, starting in 1881, which let people listen to live opera and theatre over phone lines. Radio broadcasting began experimentally in 1906 and became commercial in 1920, sending audio signals through the air. Television broadcasting started in the 1920s as an extension of radio, adding video signals. Other methods include cable radio and cable television, direct-broadcast satellite services, and webcasting over the internet.

Economic models

There are several ways to support broadcasting:

• Commercial broadcasting: stations or channels that sell time to advertisers for television advertisements or radio, often mixing this with pay cable subscription fees.
• Public broadcasting: usually non-profit stations supported by license fees, government funds, grants, or audience contributions.
• Community broadcasting: local stations run by community groups, non-profits, cooperatives, colleges, universities, cable companies, or local governments to serve local interests.
• Internet Webcast: viewers pay for virtual gifts for the host, which the platform turns into money for the host.

Broadcasters often use more than one of these business models. For example, in the United States, National Public Radio and the Public Broadcasting Service use membership subscriptions and grants, plus funding from the Corporation for Public Broadcasting, which gets money from Congress. Their corporate and charitable grants are shown in special underwriting spots, which are different from regular ads because they follow rules set by the FCC that stop them from directly selling products.

Recorded and live forms

The first regular television broadcasts began in 1937. Broadcasts can be either recorded or live. Recorded broadcasts allow for fixing mistakes, cutting out extra parts, and adding special effects like slow motion. Live events, such as sports, can also include recorded clips of important moments.

Broadcasts can travel in many ways. They can go from a radio or television studio to a transmitter and then to an antenna. They can also travel through satellites, or be sent on physical media like CDs or DVDs. Finally, people can receive broadcasts through antennas, cable, or the Internet.

Social impact

A schedule is the order in which television and radio programs are shown or aired. Both television and radio programs can be sent out using radio waves or through cables in homes. With special equipment, people can choose to pay for certain channels or programs they want to watch or listen to.

When we talk about broadcasting, we mean sending out messages from one main source to many people at once. These messages can sometimes be changed before they reach the public. It is up to each person to decide whether to listen, think about, or ignore the message. Broadcasting is used all around the world to share information and entertainment with large groups of people.

Broadcast engineering

Main article: Broadcast engineering

Broadcast engineering is a part of electrical engineering that helps send out radio and television shows to many people. It includes both the places where shows are made and the machines that send them out. People who work in broadcast engineering make sure everything works well for listeners and viewers.