1. Introduction
Terms and Definitions
Terms and Definitions
The following terms and definitions are used throughout this guide.
“ASCII”:
American Standard for Information Interchange. The standard
code consisting of 7-bit coded characters (8 bits including parity check)
used to exchange information between data processing systems, data
communication systems, and associated equipment. The ASCII set
contains control characters and graphic characters.
“Aspect ratio”:
The relationship of the horizontal dimension to the
vertical dimension of an image. In viewing screens, standard TV is 4:3,
or 1.33:1; HDTV is 16:9, or 1.78:1. Sometimes the
―:1‖ is implicit,
making TV = 1.33 and HDTV = 1.78.
“AV”:
Audio visual, or audio video.
A
“Background”
is an unscaled source, typically originating from a
computer. A background source appears at the system
’s lowest priority
— visually in back of all other sources.
“Baudrate”
：
Named of J.M.E. Baudot, the inventor of the Baudot
telegraph code. The number of the electrical oscillations per second,
called baud rate. Related to, but not the same as, transfer rate in bits
per second (bps).
“Blackburst”:
The video waveform without the video elements. It
includes the vertical sync, horizontal sync, and the chroma burst
information. Blackburst is used to synchronize video equipment to
align the video output. One signal is normally used to set up an entire
video system or facility. Sometimes it is called House sync.
“BNC”:
Bayonet Neill-Concelman. A cable connector used extensively
in television and named for its inventors. A cylindrical bayonet
connector that operates with a twist-locking motion. To make the
connection, align the two curved grooves in the collar of the male
connector with the two projections on the outside of the female collar,
push, and twist. This allows the connector to lock into place without
tools.
“Brightness”:
Usually refers to the amount or intensity of video light
produced on a screen without regard to color. Sometimes called
―black
level.
―
CAT 5
‖
:
Category 5. Describes the network cabling standard that
consists of four unshielded twisted pairs of copper wire terminated by
RJ-45 connectors. CAT 5 cabling supports data rates up to 100 Mbps.
CAT 5 is based on the EIA/TIA 568 Commercial Building
Telecommunications Wiring Standard.
“Color bars”:
A standard test pattern of several basic colors (white,
yellow, cyan, green, magenta, red, blue, and black) as a reference for
system alignment and testing. In NTSC video, the most commonly
