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Crystal Vision
Card edge operation
25
DEC101SUser ManualV1.0 05/11/03
When the Hpos setting reaches the end of a video line it wraps round and the Vpos setting
is changed to provide continuous adjustment.
With an external analogue timing reference present the delay through the board depends
on these adjustments and the relative timing of the serial input and the analogue reference.
When both horizontal and vertical position settings are zero the delay thorough the board
will be minimum and the serial output will be timed to the analogue reference as per ITU-
R BT.601.
The horizontal and vertical timing adjustments are separate for 625 and 525 line operation
and the settings are automatically maintained when the unit is powered off and restored
when the unit is powered back on.
Setting 525 (NTSC) Setup
Use rotary switch (SEL) position 7 together with the shaft encoder in 5
25
(
NTSC)
mode
ONLY
to switch Setup (pedestal) compensation ON or OFF:
SEL 7
Display Text
Description
Setup on
7.5 IRE subtracted from black level, gain increased
Setup off
Black level and gain settings assume no 7.5 IRE offset
Note:
When the board is in 525 line (NTSC) mode, the shaft encoder can be used to switch
setup (pedestal) compensation on and off.
When setup compensation is ON the display will show “setup on”. The 7.5 IRE offset
will be subtracted from the black level and the gain will be increased to compensate.
This does not affect the Y Gain and Y Offset settings.
When setup compensation is OFF the display will show “setup off”. The black level and
gain will be set assuming no 7.5 IRE offset, in the same way as for PAL inputs.
The setup mode is preserved through 625-line operation and power down.
Restoring factory defaults
If required all settings can be returned to default values. This is done by powering the
module with rotary switch (SEL) in position 9 and piano switch lever 4 UP. The display
text will be 'DEFAULTS?' To restore default settings set piano switch lever 4 DOWN.
Note:
Moving the rotary switch away from position 9 will set the board to normal operation
without overwriting the previous settings.
On no account should the SEL switch be left in position 9.