Tektronix WFM 601i, User Manual

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Glossary
WFM 601i Serial Component Monitor
Glossary–3
Luminance The signal which represents brightness, or the amount of light in
the picture. This is the only signal required for black and white pictures, and for
color systems it is obtained as a weighted sum (Y = 0.3R + 0.59G + 0.11B) of
the R, G, and B signals.
Nonlinear Distortion Refers to distortions which are amplitude-dependent.
NTSC
National Television System Committee. The organization which
developed the television standard currently in use in the United States, Canada,
and Japan. Now generally used to refer to that standard.
PAL
Phase Alternate Line. Refers to one of the television systems used in
Europe and many other parts of the world. The phase of one of the color
difference signals alternates from line to line to help cancel out phase errors.
RF Radio Frequency. In television applications, RF generally refers to the
television signal after the picture carrier modulation process
RGB Red, Green, and Blue. Also referred to as GBR. The three primary colors
used in color television’s additive color reproduction system. These are the three
color signals generated by the camera and used by the picture monitor to produce
a picture.
R–Y One of the color difference signals obtained by subtracting luminance (Y)
from the red camera signal.
Saturation
The property of color which relates to the amount of white light in
the color. Highly saturated colors are vivid, while less saturated colors have more
white mixed in and, therefore, appear pastel. For example, red is highly
saturated, while pink is the same hue, but much less saturated.
In signal terms, saturation is determined by the ratio between luminance level
and chrominance amplitude. It should be noted that a vectorscope does not
display saturation; the length of the vectors represents chrominance amplitude. In
order to verify that the saturation of the colors in a color bar signal is correct,
you must check luminance amplitudes with a waveform monitor in addition to
observing the vectors.
Termination In order to accurately send a signal through a transmission line,
there must be an impedance at the end which matches the impedance of the
source and of the line itself. Amplitude errors and reflections will otherwise