Tektronix 2200 Manual Do Utilizador

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Glossary
G-12
Split Key:  
A key mode in which the key 
signal and the key video are from different 
sources.
Spotlight:  
A highlight effect produced by 
superimposing a full-strength video signal 
shaped by a wipe pattern over an 
attenuated (darkened) signal from the 
same video source.
Subcarrier:  
A sine wave signal which is 
imposed on a video signal as a color 
reference. Subcarrier also forms color 
burst. The frequency of subcarrier is 3.58 
MHz in NTSC and 4.43 MHz in PAL.
Switcher (Vision Mixer):  
An electronic 
device that takes video signals from any of 
several sources (such as cameras, VTRs, 
character generators, etc.) to combine 
video signals and produce video effects. 
(Also see Audio Mixer.)
Sync:  
The portion of an encoded video 
signal which occurs during blanking and 
is used to synchronize the operation of the 
equipment. Horizontal sync occurs during 
the blanking period in each horizontal 
scanning line, and vertical sync occurs 
during the vertical blanking period.
Synchronous:  
A mode of computer 
operation where all tasks, regardless of the 
time they take for execution, are allotted 
specified time cycles. (Also see 
Asynchronous.)
System:  
A grouping of assemblies which 
perform multiple related tasks. (Also see 
Assembly and Component.)
T
Terminate, Termination:   
To complete a 
circuit by connecting a resistive load to it. 
A video termination is typically a male 
BNC connector which contains a 50-ohm 
or 75-ohm resistive load. Any unused 
looping inputs must be terminated to 
ensure proper signal levels.
Time Base Corrector:  
An electronic device 
used to correct video signal instability.
Title, Caption, Title Key:  
A key derived 
from a title signal generated by a character 
generator, graphics camera, etc. The title 
fill may be either a matte or title video.
Transcoder:  
A device for converting one 
component form to another, as in RGB to Y, 
R-Y, B-Y. Also called a translator.
Transition: 
  An operation which changes 
backgrounds and/or adds or removes 
titles. A transition can be in the form of a 
wipe, mix, or cut.
V
Vertical Interval:  
The portion of the video 
signal that occurs between the end of one 
field and the beginning of the next. During 
this time, the electron beams in the 
monitors are turned off so that they can 
return from the bottom of the screen to the 
top to begin another scan.
Video:  
An electrical signal used to carry 
visual information. Composite video 
includes sync and blanking signals. 
Noncomposite video does not include 
sync and blanking.