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VP400 Series Video Pro
Form7343A
Operation Manual
13
Gating Menu
A Gating menu is displayed by pressing the Gating pushbutton. This menu lists options to
modify the output video or sync signals. The gating options shown in this menu vary depending
on the selected signal type and format. The middle of the Gating menu indicates the signal type
and video pattern currently selected.
ACS, DCS, DSS Gating:
The right side of
the gating menu provides three choices of
sync types. The native sync type for the
selected format is marked with an asterisk.
The sync types are abbreviated as ACS
(Analog Composite Sync), DCS (Digital
Separate Sync, and DSS (Digital Separate
Sync). Here is a brief description of each
sync type.
ACS (Analog Composite Sync):
Vertical and horizontal sync pulses
are included with the Y (luminance),
G (Green), or Composite Video
signals
.
Levels are analog, causing an
approximate 0.3V sync signal swing.
DCS (Digital Composite Sync):
TTL-
level
vertical and horizontal sync
pulses are separate from the video, but
are combined on a single wire
connection as a composite signal.
DCS is used in analog RGB color
video signal types.
DSS (Digital Separate Sync): TTL-
level vertical and horizontal sync
pulses are separate and contained on
separate connector pins and wires
between the generator and display.
Red, Green, Blue Gating
: The left side of
the gating menu provides on/off control of the
individual R, G, B video outputs. For
example, pressing the pushbutton beside the
RED display indicator turns on or off the red
color. An asterisk indicates the color output is
active. Color gating is not available in the
YPbPr or ATSC RF signal types. When the
color cannot be gated on or off, pressing the
pushbuttons beside the RED, GRN and BLU
display indicators will not turn off the output
and the asterisk stays on.
Sync Polarity Gating:
A Sync Polarity
selection in the bottom left of the display
switches the sync polarity from positive (+) to
negative (-). This selection is available in the
analog RGB signal type.
Trilevel, Bilevel Sync Gating:
A sync type
selection is available in the HDTV/SDTV
YPbPr signal types. The sync type may be
bilevel or trilevel.
Bilevel Sync: Two-level sync pulse
combined on the luminance or Y
signal.
Trilevel Sync: Three-level sync pulse
combined on the luminance or Y
signal.
Black Setup On/Off Gating:
A black setup
level may be added or deleted from the NTSC
signal type. Pressing the pushbutton cycles
the black setup from on to off. Black setup
establishes black at 7.5 IRE level. Turning
black setup off reduces the black level
portions of the test pattern signals to 0 IRE.