Tektronix WFM601, Руководство по обслуживанию

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WFM601 Serial Component Monitor
Glossary–1
Glossary
AC Coupled A connection which removes the constant voltage (DC compo-
nent) on which the signal (AC component) is riding. Usually implemented by
passing the signal through a capacitor.
APL
(Average Picture Level.) The average signal level (with respect to
blanking) during active picture time, expressed as a percentage of the difference
between the blanking and reference white levels.
Back Porch
The portion of the video signal which lies between the trailing
edge of the horizontal sync pulse and the start of the active picture time. Burst is
located on back porch.
Bandwitdth
The range of frequencies over which signal amplitude remains
constant (within some limit) as it is passed through a system.
Baseband
Refers to the composite video signal as it exists before modulating
the picture carrier. Composite video distributed throughout a studio and used for
recording is at baseband.
Black Burst (NTSC)
Also called ”color black,” black burst is a composite
video signal consisting of all horizontal and vertical synchronization informa-
tion, burst, and usually setup. Typically used as the house reference synchro-
nization signal in television facilities.
Black Burst (PAL)
Also called ”color black,” black burst is a composite video
signal consisting of all horizontal and vertical synchronization information and
burst. Typically used as the house reference synchronization signal in television
facilities.
Blanking Level
Refers to the 0 IRE level for NTSC systems (0.3 volt level,
with respect to sync tip, for PAL systems) which exists before and after
horizontal sync and during the vertical interval.
Bowtie
Bowtie display. A display used to assess relative timing and gain
through a three channel component system.
Breezeway The portion of the video signal which lies between the trailing
edge of the horizontal sync pulse and the start of burst. Breezeway is part of
back porch.
Broad Pulses
Another name for the vertical synchronizing pulses in the
center of the vertical interval. These pulses are long enough to be distinguished
from all others, and are the part of the signal actually detected by vertical sync
separators.