Science Museum

https://collection.sciencemuseumgroup.org.uk/objects/co8459292/british-post-office-monarch-120-system-digital-pabx-private-automatic-branch-exchange-equipment-cabinet 

The science museum's Monarch 120 has an 'interesting' Control Shelf

from the picture it looks like it has 3 cpu cards

an 8085 type in slot 05

two 8088 types in slots 13 and 14

Details

Category:

Telecommunications

Object Number:

2015-488

Materials:

metal (unknown) and plastic (unidentified)

Measurements:

overall (estimated weight): 1720 mm x 560 mm x 600 mm, 500 kg

type:

electronic device

credit:

BT Heritage and Archives

British Post Office Monarch 120 system digital PABX (private automatic branch exchange) equipment cabinet

1980

British Post Office Monarch 120A system digital PABX (private automatic branch exchange) equipment cabinet, made by Plessey Office Systems Ltd, British, design introduced into service 1980

Operator console for British Post Office Monarch 120 system digital PABX (private automatic branch exchange)

1980

Operator console for British Post Office Monarch 120A system digital PABX (private automatic branch exchange), made by Plessey Office Systems Ltd, British, design introduced into service 1980

Fault analysis equipment for British Post Office Monarch 120 system digital PABX (private automatic branch exchange)

1980-2000

Fault analysis equipment for British Post Office Monarch 120A system digital PABX (private automatic branch exchange), made by Texas Instruments, 1980-2000

Collection of manuals for British Post Office Monarch 120 system digital PABX (private automatic branch exchange)

9 items

Technical manual: ‘Monarch 120 A, B and Compact Call Connect Systems, Man Machine Interface (MMI) Commands with Abbreviated Maintenance Information’

10

Sales leaflet: ‘The Monarch 120 Call Connect System’

210

Technical manual for use by prospective purchasers: ‘The Monarch 120 Call Connect System, Technical Description Part 1’

10

Technical manual for use by prospective purchasers: ‘The Monarch 120 Call Connect System, Technical Description Part 2’

10

Collection of technical manuals and sales documentation relating to the BT Monarch Call Connect System digital PABX

1980

Collection of technical manuals and sales documentation relating to the BT Monarch Call Connect System digital PABX (private automatic branch exchange) including British Telecom sales leaflet, 4-page A4 colour folder, ‘The Monarch 120 Call Connect System’ (1980); Technical manual for use by prospective purchasers, British Telecom, ‘The Monarch 120 Call Connect System, Technical Description Part 1’, A4, comb-bound (1981); Technical manual for use by prospective purchasers, British Telecom, ‘The Monarch 120 Call Connect System, Technical Description Part 2’, A4 comb-bound (1981); Technical manual, British Telecom, ‘Monarch 120 A, B and Compact Call Connect Systems, Man Machine Interface (MMI) Commands with Abbreviated Maintenance Information’, 148 mm x 109 mm, comb-bound (1987); Technical Manual, ‘Monarch System User Guide’, Issue 1 October 1993, for the Monarch Call Connect system, about 100 sheets A4, unbound; Technical manual, ‘Monarch Field Manual for BT field engineers’, Issue 1 April 1996, for the BT Monarch Call Connect system, about 200 sheets A4, unbound; Sales information for the Plessey CDSS1, 4-page A4 colour folder (1980) with five A4 single-sheet leaflets loosely inserted describing variants of the Plessey own-brand version of the Monarch Call Connect system: Plessey CDSS 120; Plessey CDSS 240; Plessey CDSS 60/120 (single cabinet system); Plessey CDSS 60/120 (double cabinet system); and Plessey Paxtel electronic PAX., British, 1980-1996

Collection of sales documentation and technical manuals relating to the BT Monarch Call Connect System digital PABX (private automatic branch exchange)

7 items

Sales information for the Plessey CDSS1

210