Operation of entrance telephone
Ritto TwinBus entrance system
SX303/353isdn
Caution!
!
Connect base power unit 4753/01 and additional unit TFV4680/00 using
enclosed bus connector.
Door type 2 (DTMF)
For details of connecting entrance telephones with DTMF control (door type 2), refer to
the example below.
Deutsche Telekom DoorLine
146
SX303/353isdn