Sony SEG-2550 Operating Instructions Manual page 44

6] INDICATION selector
Abus/B bus select section
Abusi/B bus select buttons
Select
the pictures used
for wipe, mixing
and external key.
Pictures can be selected by A bus select buttons and B bus
select buttons separately.
BACKGROUND selectors
WHT: White background
BLK: Black background
EFF (effect) lever
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