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Blanking
This selection reveals the Blanking sub-menu that
allows picture blanking to be adjusted.
Using both the Front Porch and Back Porch controls
allows the blanking position and width to be adjusted
by setting independant start and finish points.
It should be noted that these controls will not allow
blanking to exceed the limits for valid D1 signals.
Control Functions
Front Porch
This allows the front porch to be
adjusted.
The width may be adjusted in 148 ns
steps. Preset value is 1333 ns.
Back Porch
This allows allows the back porch to
be adjusted.
In NTSC mode the width of the back
porch may be adjusted in 148 ns
steps.
Preset value is 4741 ns.
In PAL mode the width of the back
porch may be adjusted in 148 ns
steps.
Preset value is 5630 ns.
Field 1, Field 2
This reveals another sub-menu for selecting particular
lines in the vertical interval of field 1 or field 2 that may
be blanked or unblanked.
Field 1
Any lines in the range 10 to 20 (NTSC)
or 7 to 22 (PAL) may be selected to
be blanked (text highlighted) or
unblanked (text normal)
Field 2
Any of the lines in the range 272 to
282 (NTSC) or 320 to 335 (PAL) may
b e s e l e c t e d t o b e b l a n k e d o r
unblanked.
Operating Modes
This function allows the decode standard to be set.
The unit may be forced to decode in either PAL or
NTSC by making the appropriate selection; when
Auto is selected the unit will detect the signal standard
and automatically decode in that standard.
Factory Defaults
Selecting this function sets all parameters to factory
set default settings.
SECTION 4
Operation
MDD550050398
Software Version 1.3.1 onwards 4.15