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Burst VS-4X1 Vertical Interval 4x1 Active Switcher-by-Burst Electronics
The VS4X1 is a four input, one output video switcher.
A special feature of the VS4X1 is digital logic that inhibits selection of an unused input, i.e.
one where no video is present.
The output is DC clamped to zero volts.
This allows for jump free switching between genlocked sources.