Uniden DSC Series - Manual (Page 53)

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4. You can now enter the USER MMSI
code. Press CH
▲ to increase the
number, CH
▼ to decrease. The number
will be entered when SELECT is
pressed, and the blinking moves to the
right.
5. After the final digit is entered, press and
hold SELECT. The radio returns to
USER MMSI screen.
Note: You can only program your radio
twice with an MMSI number. After
that, send your radio to Uniden for
factory service.