Crystal Vision
Appendix 1
Synchroniser controls
Genlock mode
The SYN-A 3G has two modes of operation, as a synchroniser or as a user set fixed delay. In
synchroniser mode the external reference can be either Black and Burst or a Tri-level/Bi-level
sync containing no burst. Delay mode is achieved by locking the SYN-A 3G to the incoming
video rather than the external reference.
On loss of video input
Should the input video be lost due an up-line fault such as an equipment failure, the SYN-A
3G can be set to give a selection of responses. This response can be chosen from the following
list: 100% colour bars, Blue, Black, Freeze last good frame. A three second delay can also be
introduced where the picture will freeze for three seconds before reverting to the mode
selected.
Selecting no output will remove the carrier from the output.
Freeze function
Selecting the freeze function will freeze the output again according to the user selection. When
selecting freeze choose between 100% colour bars, Black, or the last good frame. Whilst
frozen the output will remain timed to the external reference but any audio will mute.
Video delay and output timing
There are two user controls available to set the input to output video delay. The first control
gives a coarse setting of delay in whole frames up to three frames of delay and the second set
of controls gives a variable delay in lines and pixels. The maximum amount of variable delay
that can be set is one field; dialling in any number of lines or pixels that exceed one field will
result in the delay being limited to the number of lines per field of any input format.
Note:
The final input to output delay will be reliant on several factors such as
synchroniser delay, audio resampling and Dolby E alignment.
Force output
The SYN-A 3G has the ability to have its output format forced without an input present. This
ability is useful when setting up a system and checking signal paths. When in forced mode the
output can then be set to any of the formats handled by the SYN-A 3G and give either a 100%
colour bars or black output as selected by the ‘On loss of input’ control.
SYN 3G/SYN-A 3G User Manual R1.3
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9 July 2019
