Introduced in 1937, this combined Bakelite table handset telephone for use by the BPO in CB & Automatic areas on PBX extensions, systems that require recall facilities and certain extension plans.

The press button label would have been ordered separately.

Supplied with one press button.

Suffix identification:-
Telephone No. 330CB - No dial - blank plate fitted.
Telephone No. 330L - Figured and lettered dial installed.
Telephone No. 330F - Figure only dial installed.

British Ericsson made some of these instruments for the BPO.
Click here to go to the Ericsson CB model No. N1366.
Click here to go to the Ericsson Auto model No. N1003.

Circuit diagram N430.

Click here for the circuit diagram - Web users - CD users

Click here for Button labels  - Web users - CD users

Additional good quality pictures

History, Technical and General Information on 300 type telephones

Keys for use in 300 type Wall and Table Telephones

Lamp Fittings

Labels that fit in the sliding tray

Adjustment of Magneto bells

Collectors information

General fault finding on your phone

How to restore Bakelite

Dismantling the Handset

Dismantling your Telephone No. 330

How to wire your Telephone No. 330 to make it work on Plug and Socket

General fault finding on your phone

Comparison chart of GPO 300 type telephones



Typical 300 type chassis showing dial cord wiring colours


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Last revised: June 12, 2017