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6.5.4. Setting the Free-Running Frequency
Video
Free-run freq
-256 to 256
0
6.5.5. Setting the Fine Phase of the Output Video – NTSC/525 Video
Video
525 fine phase
-128 to 127
0
6.5.6. Setting the Fine Phase of the Output Video – PAL-B/625 Video
Video
625 fine phase
-128 to 127
0
7737CE Composite Encoder with Image Enhancement
This control allows you to calibrate the free-running frequency of the on-board
Voltage Controlled crystal Oscillator (VCXO). This oscillator provides the time-
base when either operating without a reference input (free-running) or when
running with a reference and the reference video is removed.
To calibrate the free-running frequency, use this or a similar procedure:
•
Turn off genlocking with the "Genlock source" control or remove
reference video from the reference input. Wait for the VCXO to stabilize
at it's free-running frequency.
•
Apply the composite analog monitoring output video to a vector scope
that is externally referenced to the signal (usually plant reference black)
that you are trying to frequency match.
•
Adjust this control until the vectors spin slowly.
•
Turn genlocking back on or apply reference video.
With this control, you can set the horizontal fine phase timing of the output
video with respect to the Genlock when operating in NTSC/525 video mode and
locking to the reference input (this control is not available when locking to the
input video). Increasing the value will delay the output video. There is
approximately 250 ns range on this control.
Warning: For a set output horizontal phase, there are a few fine phase/H phase
combinations that will achieve the same position. For best results, set this
control to 0, set the H phase to get within 37ns of the desired position, then
adjust this control to get closer.
With this control, you can set the horizontal fine phase timing of the output
video with respect to the Genlock when operating in PAL/625 video mode and
locking to the reference input (this control is not available when locking to the
input video). Increasing the value will delay the output video. There is
approximately 250 ns range on this control.
Warning: For a set output horizontal phase, there are a few fine phase/H phase
combinations that will achieve the same position. For best results, set this
control to 0, set the H phase to get within 37ns of the desired position, then
adjust this control to get closer.
Revision 1.0
7700 MultiFrame Manual
7737CE-17
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