Lanier Copier System Edition Operating Instructions Manual page 1215

Multi-port
When the optional ISDN Unit or optional Extra G3 Interface Unit is installed, communications can take
place simultaneously through two lines at once.
Option
Without option
Extra G3 Interface Unit
ISDN Unit
Note
A maximum of two communications can take place simultaneously.
You cannot perform two Immediate Transmissions simultaneously.
If two fax messages are received simultaneously, they cannot be printed out at the same time.
If two communications are in progress, the display shows the first communication that was initiated.
Operating InstructionsFacsimile Reference (option) <Advanced Features>
Available Line Types
PSTN
PSTN+PSTN
PSTN+ISDN
ISDN
Available Protocol Combinations
G3
G3+G3
G3+G4
or
G3 (ISDN)+G4
G3 (ISDN)+G4
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