Mechanical televisionMechanical television or mechanical scan television is an obsolete television system that relies on a mechanical scanning device, such as a rotating disk with holes in it or a rotating mirror drum, to scan the scene and generate the video signal, and a similar mechanical device at the receiver to display the picture. This contrasts with vacuum tube electronic television technology, using electron beam scanning methods, for example in cathode ray tube (CRT) televisions.
Film chainA film chain or film island is a television – professional video camera with one or more projectors aligned into the photographic lens of the camera. With two or more projectors a system of front-surface mirrors that can pop-up are used in a multiplexer. These mirrors switch different projectors into the camera lens. The camera could be fed live to air for broadcasting through a vision mixer or recorded to a VTR for post-production or later broadcast. In most TV use this has been replaced by a telecine.
Film recorderA film recorder is a graphical output device for transferring images to photographic film from a digital source. In a typical film recorder, an image is passed from a host computer to a mechanism to expose film through a variety of methods, historically by direct photography of a high-resolution cathode ray tube (CRT) display. The exposed film can then be developed using conventional developing techniques, and displayed with a slide or motion picture projector.
Rec. 709Rec. 709, also known as Rec.709, BT.709, and ITU 709, is a standard developed by ITU-R for image encoding and signal characteristics of high-definition television. The most recent version is BT.709-6 released in 2015. BT.709-6 defines the Picture characteristics as having a (widescreen) of 16:9, 1080 active lines per picture, 1920 samples per line, and a square pixel aspect ratio. The first version of the standard was approved by the CCIR as Rec.709 in 1990 (there was also CCIR Rec.
Pilot signalIn telecommunications, a pilot signal is a signal, usually a single frequency, transmitted over a communications system for supervisory, control, equalization, continuity, synchronization, or reference purposes. In FM stereo broadcasting, a pilot tone of 19 kHz indicates that there is stereophonic information at 38 kHz (the second harmonic of the pilot tone). The receiver doubles the frequency of the pilot tone and uses it as a frequency and phase reference to demodulate the stereo information.
