Furuno Felcom 50 Operator's Manual page 105

Switching between MPDS and ISDN mode
The connection window provides sensing on the telephone number.
If dialing an international number instead of **94#, the terminal switches back to
ISDN mode of operation.
Examples:
Dialing **94#
(no subscriber number is sent to the Net provider).
Dialing 008166850170
MPDS via default Net service provider
Note: Hash # may be omitted on some
PCs/Windows versions.
ISDN mode.
6. DATA COMMUNICATION
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