Combined, Bakelite cased, table telephone used by the BPO in CBS No's 1, 2, 3 & Magneto areas on private circuits without transmission feeds and in mobile vans.

Supplied to the BPO by Ericsson, their Model N8440.

Adjustment of Magneto bells

Circuit diagram - N496.

Diagram for the Button labels  - N620.

History, Technical and General Information on 300 type telephones

Collectors information

General fault finding on your phone

How to restore Bakelite

Dismantling the Handset

Dismantling your Telephone No. 312

Keys for use in 300 type Wall and Table Telephones

Comparison chart of GPO 300 type telephones


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Last revised: December 02, 2018