ROLM CBX II ACD (7000/8000)

PXML No. 124
APPROVAL No. NS/1210/23/H/452742

The Rolm CBXII Automatic Call Distribution is a stored program computer controlled modular designed telephone switching system. Voice frequency connections through the switch uses Pulse Code Modulation for speech to digital conversion, and Time Division Multiplexing for switching the digital pulse train.
Earlier systems are known as 7000 type systems, These systems are 1 to 3 cabinet systems and use ET5300 type telephones as agent positions, There is also an additional Adaptor Cabinet which houses cards which allows connection of early Rolm trunk cards co the UK PSTN. Some sites have BT Power systems 2000b fitted as standby power.
Later systems are known as 8000 type systems. These systems use ET5300A type telephones as agent position and Rolmphones 120, 240 and 400 as feature phones. A small non-redundant system, the VSCBX, is also available.
Some later 8000 installations use a stand alone ELTEK Power Cabinet, which provides system voltages and standby batteries.
Conversion is possible from a 7000 type system to a "hybrid 8000" type system.

Made by Rolm Telecommunications.
Distributed initially in the UK through Plessey (GPT and now Siemens)
Systems were later distributed through IBM UK Ltd

Early systems were installed by Plessey Telecommunications and Telephone Rentals. Later systems have been installed by IBM UK Ltd.
Extensions to existing systems should only be installed by IBM UK Limited.
Maintained originally by BT but IBM UK Ltd were approved maintainers for liberalised system ONLY, (those are systems brought into service after lst July 1986).
Equipment      Software Disc     Header

7000 Type      7000 or 7000I     (Release 7)
8000 Type      8000I

When the engineer signs onto the system the printed header will state the software fitted (either release 7 or 8). Software/patches fitted are recorded on the hardware map.

Telephone 01256 478166

DESCRIPTION                                      PART NO
CPU 2                                            MN 85030
CPU 3                                            MN 85010
CPU 4                                            MN 85020
MEMORY CONTROLLER                                MN 84040
DTDM NETWORK CONTROLLER 1                        MN 85060
DTDM NETWORK CONTROLLER 2                        MN 85070
+I/D BUS SWITCH                                  MN B5090
+REAL TIME CLOCK                                 MN 85080
+QUAD SERIAL I/O                                 MN B5920
FLOPPY DISK INTERFACE                            MN 85360
+2-CHANNEL SERIAL I/0                            MN 87600
+ETA-1                                           MN 85660
+ETA-2                                           MN 85670
8 CHANNEL I/F                                    MN B5540
16 CHANNEL CODER                                 MN 85510
16 CHANNEL DECODER                               MN 85520
EXPANDER                                         MN 85500
+CPU A                                           MN B6200
+CPU B                                           MN 86250
TCC CARD                                         MN 75080A
+256K MEMORY                                     MN 86130B
MEMORY CONTROLLER                                MN 86200
ROLMPHONB INTERFACE I                            MN 78011A
ROLMPHONE INTERFACE II                           MN 79012
INTERSHELF  BUS                                  MN B5990
FLOPPY DISC DRIVE                                MN 88981
FLOPPY DISC I/F                                  MN 85360B

Some cards have been superseded by later revision cards.  All cards with
same description are compatible unless stated.


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Last revised: December 19, 2010