Tektronix 2200 Manual Do Utilizador

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Glossary
G-9
Modem:  
A device that converts signals 
from a form compatible with data 
processing equipment to a form 
compatible with transmission facilities 
(such a telephone lines) and vice versa.
Monitor:  
A device used for viewing video 
signals.
Multiplier:  
An electronic control circuit, the 
output of which is the product of a video 
input and a control input, or the product of 
two control signal inputs.
N
NAB:  
National Association of 
Broadcasters.
Nanosecond (ns):  
One billionth of a 
second.
Noise: 
 Interference present in a video or 
audio signal.
Non-Additive Mix (NAM):  
A transition 
between two video signals in which only 
the signal with the largest instantaneous 
amplitude at any point in the picture is 
visible.
NTSC:  
The U.S. standard for encoded 
color TV transmission developed by the 
National Television System Committee. 
This standard uses a 3.579545 MHz 
subcarrier whose phase varies with the 
instantaneous hue of the televised color, 
and whose amplitude varies with the 
instantaneous saturation of the color. A 
single frame (picture) in this standard 
consists of 525 scanning lines. One frame is 
shown every 1/29.94 of a second. (Also see 
PAL.)
O
Octal: 
A numerical notation system using a 
base of 8. (Also see Binary and Hex.)
On-Air:  
The state of a signal which is 
present at the switcher Program output. 
Operating Program:  
The complex sequence 
of instructions that determines the ability 
of a computer to both sequentially and 
concurrently run specific programs. (Also 
see Program and Routine.)
Outline:
  A title enhancement in which 
only the outline of the key is visible, with 
the same (background) video outside and 
inside the outline.
P
PAL (Phase Alternating Line):  
transmission standard for encoded color 
television used in Europe and some other 
parts of the world. This standard uses a 
4.43361875 MHz subcarrier which is 
alternated 90 degrees in phase from one 
occurrence of a line to the next to minimize 
hue errors in color transmission. A single 
frame (2 fields) in this standard consists of 
625 scanning lines. One frame is produced 
every 1/25 of a second. (Also see NTSC.)
Pattern Border:  
A variable-width colored 
border that can be inserted at the pattern 
edge in a wipe transition between two 
video signals. The border is filled with 
matte video from the wipe border matte 
generator.