KE LOGEM 928, Operation Manual

Page: 135 / 200

135 Operation Manual V.34 - Modems, Version 07/97
Chapter 6
Dial Backup Features
6 Dial Backup Features
6.1 Function of the Dial Backup Board
Attention! The dial backup features are not available for the top
rail version LGH 28.8D1!
Due to the implementation of the dial backup board the LOGEM
®
928
and the LOGEM ® LGM 28.8D1 offer a further line interface. The line
interface allows for 2 or 4 wire leased line operation. The additional line
interface is not applicable for switched line applications. The dial backup
board has to be employed for 4 wire leased line connections of group 0
and for private 4 wire leased line implementation. During dial backup
applications the leased line connection is established generally using the
dial backup (DBU) board. The secondary path (switched connection) is
realized with the line interface of the main board. The DBU board has no
DIP switches or jumpers as the board is detected automatically by the
modem after installation.
6.2 Installation of the DBU Board (Standalone Version)
First remove all cables from your LOGEM ® 928 and disconnect the
telephone access line from your wall socket.
Now you can open the modem housing that consists of two basic parts
that are connected with a snap-in bracket. Please open the housing very
carefully using a screwdriver that has to be inserted into the slots at the
bottom of the device. Make sure to insert the screwdriver at the outer
side of the slot near to the devices housing in order not to damage the
snap-in bracket. Open the snap-in brackets (ref. to fig. on the following
page) carefully with a slight upward movement of the screwdriver. Open
the housing carefully with your hands.