Introduced in 1950, this Bakelite cased, combined handset wall telephone (equivalent to the table Telephone No. 310) was used by the BPO in auto areas on shared service with selective ringing and metering. 

The telephone had a single press button situated above the dial.

The phone has an integral relay that stops bell tinkle.  This relay is fitted in a Bellset No. 41A, which was always installed with the table model, the Telephone No. 310.

Mark 1 & Mark 2 - do not exist.
Mark 2A - has a Receiver, Inset No. 2P in the handset and switch bracket and plungers of an improved design.

The phone case is released from the back plate by one screw on the right hand side of the case.  The whole body, complete with chassis, swings open to the left, away from the back-plate which is fixed to the wall.

This phone was superseded by the Telephone No. 321 which was fitted with a Thermistor (this reduced the number of components and thus the cost of the phone).

Supplied to the BPO by British Ericsson, their model No. N1071D.

Diagram for telephone circuit - N411.

Diagram for Button labels - N620.


Keys for use in 300 type Wall and Table Telephones

History, Technical and General Information on 300 type telephones

How to wire your Telephone No. 311 to make it work on Plug and Socket

Collectors information

Comparison chart of GPO 300 type telephones

Click here for an article from the Ericsson Bulletin

The chassis when installed in the case
Chassis removed - showing the rectifiers and additional capacitor
Another view of the chassis showing the relay underneath the capacitor
Telephone Paster diagram




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Last revised: June 06, 2020