Electronics International Super Clock SC-5 Operating Instructions Manual page 13

To display and set the Minutes Lock Configuration, push the "RESET" Button until you see a
"Loc" or uULoc" in the display. Use the "STEP" Switch to toggle the display between "Loc" and
"ULoc." The "Loc" indicates the Zulu and Local minutes will be locked together. (i.e., the Zulu
and Local minutes will always read the same. If you change one, the other will automatically
change also). If you operate your aircraft only in one hour time zones, set the display to "Loc."
In this configuration when the Local Clock is set to a standard the Zulu Clock minutes will
automatically be set to the correct time.
If you operate your aircraft in half hour time zones, set the display to "ULoc." In this configura-
tion the Local and Zulu Clock work independently of each other.
To go back to programming the Zulu Clock or Local Clock, continue to push the "START/
STOP" Button until you get the appropriate display.
d) To Exit - To exit the Power-up Programming Mode, momentarily push both the "START/
STOP" and "RESET" Buttons at the same time.
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