Adtec digital mediaHUB-HD 422 (version 1.01.10_M_2) Manual - Manual (Page 57)

The VBI Tab
The controls on this tab govern video signal components that can be inserted into the Vertical Blanking Interval.
The tab's controls are grouped into two sub-tabs: Captions and Teletext.
Captions
Screenshot:
Image reduced for clarity
Controls
Control Function Options API Command
VBI Source selects input source for VBI data
Composite
SDI
*.ECMD VBS
Closed
Caption
Closed Captions can be turned off for the current stream/encode or set to
ATSC Mode for EIA-708 closed caption insertion.
This control is available for High Definition only.
608
708
608->708
DVS157
*.ECMD CLC
[selection]
Teletext
Screenshot:
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