Analog television

Analog television or analogue television is the original television technology that uses analog signals to transmit video and audio. In an analog television broadcast, the brightness, colors and sound are represented by rapid variations of either the amplitude, frequency or phase of the signal.

Analog signals vary over a continuous range of possible values which means that electronic noise and interference becomes reproduced by the receiver. So with analog, a moderately weak signal becomes snowy and subject to interference. In contrast, a moderately weak digital signal and a very strong digital signal transmit equal picture quality. Analog television may be wireless or can be distributed over a cable network using cable converters.

All broadcast television systems preceding digital transmission of digital television (DTV) used analog signals.

Analog television around the world has been in the process of shutting down since the late 2000s.

Development

The earliest systems were mechanical television systems which used spinning disks with patterns of holes punched into the disc to scan an image. A similar disk reconstructed the image at the receiver. Synchronization of the receiver disc rotation was handled through sync pulses broadcast with the image information. However these mechanical systems were slow, the images were dim and flickered severely, and the image resolution very low. Camera systems used similar spinning discs and required intensely bright illumination of the subject for the light detector to work.

The End

The End may refer to:

Arts, entertainment, and media

Film

Games

Analog

Analog or analogue may refer to:

In arts and entertainment

Magazines

In music

Other uses in arts and entertainment

In science and technology

In chemistry