Tektronix WFM601, Руководство по обслуживанию

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Glossary
Glossary–2
WFM 601 Serial Component Monitor
Bruch Blanking (PAL) A 4–field burst blanking sequence employed in PAL
signals to ensure that burst phase is the same at the end of each vertical interval.
Burst (NTSC)
A small reference packet of the subcarrier sine wave, typically 8
or 9 cycles, which is sent on every line of video. Since the carrier is suppressed,
this phase and frequency reference is required for synchronous demodulation of
the color information in the receiver.
Burst (PAL)
A small reference packet of the subcarrier sine wave sent during
the horizontal blanking interval on every line of video. Since the carrier is
suppressed, this phase and frequency reference is required for synchronous
demodulation of the color difference signals in the receiver.
B–Y (NTSC) One of the color difference signals used in the NTSC system,
obtained by subtracting luminance from the blue camera signal. This is the
signal which drives the horizontal axis of a vectorscope.
B–Y (PAL)
One of the color difference signals used in the PAL system,
obtained by subtracting luminance (Y) from the blue camera signal (B).
Chrominance Chrominance refers to the color information in a television
picture. Chrominance can be further broken down into two properties of color:
hue and saturation.
Chrominance Signal
The high–frequency portion of the video signal which
is obtained by quadrature amplitude modulation of a 3.58 MHz (NTSC) or 4.43
MHz (PAL) subcarrier with R–Y and B–Y information.
Color Black
See Black Burst.
Color Difference Signals
Signals used by color television systems to convey
color information in such a way that the signals go to zero when there is no color
in the picture. R–Y, B–Y, I, and Q are all color difference signals for the NTSC
system; U and V are color difference signals for the PAL system. Component
system color difference signal is Y, P
B
, P
R
as specified by SMPTE and CCIR
standards.
Color Gamut
The area between minimum and maximum reproducible limits
for elements of the color difference or RGB signals.
Component Video
Video which exists in the form of three separate signals,
all of which are required in order to completely specify the color picture. For
example, R, G, and B; or Y, R–Y, and B–Y.
Composite Video
A single video signal containing all of the necessary
information to reproduce a color picture. Created by adding quadrature
amplitude modulated R–Y and B–Y to the luminance signal for NTSC systems
or U and V to the luminance signal for PAL systems.
CW Continuous Wave. Refers to a separate subcarrier sine wave used for
synchronization of chrominance information.