TELEPHONE No. 328


Introduced in 1937, this combined table handset telephone (with magneto bell) was used in both C.B. & Automatic exchange areas on extension plans.

This telephone had a tray for the subscribers personal directory but as from June 1940 the tray was not fitted and instead the telephone was supplied with a Tray, Dummy, D62099 (a blank plate).  This was probably a war time cost saving, as in late 1947 the tray was re-introduced.

There is provision in the case for three keys/press buttons.  A key unit can be fitted on the internal chassis.

The original telephone used a Coil, Induction No. 22, but this was replaced by the Coil, Induction No. 27 later in life.  The wiring never changed.

Available in the colours: Black, Jade green, Chinese red and Ivory.

Some were modified for scrambler use and called the Telephone SA5030.

The Mark 1 - has a Receiver, Inset No. 1L in the handset and switch bracket with plungers of the early type.
The Mark 1A - has a Receiver, Inset No. 1L in the handset and switch bracket with plungers of an improved type.
The Mark 2 - has a Receiver, Inset No. 2P in the handset and switch bracket with plungers of the early type.
The Mark 2A - has a Receiver, Inset No. 2P in the handset and switch bracket with plungers of an improved design.

Superseded by the Telephone No. 710.

Telephone included:-
1 x Bell No. 59A, Unmounted.
1 x Bell-gong No. 2.
1 x Bell-gong No. 2A Nickelled.
1 x Coil, Induction No. 27.
1 x Condenser, M.C. No. 97.
1 x Cord, Instrument No. 5/28E, 5" (for Dials, Auto., only).
1 x Dial, Automatic S.S., No. 10 ... or Dummy, No.3 (Colour).
1 x Part No. 3/SCA/17 (Colour)
1 x Telephone No. 164 (Colour)
1 x Tray, D 62076 (Colour) or D1/62833 (Colour) or 1 x Tray, dummy, D 62099, Black.

To be requisitioned separately as required:-
1 x Block, Terminal No. 20/ . . (Colour)
1 x Key No. 303A or 304A.
1 x Label No. 160.
1 x Label No. 252, Black.
1 x Part No. 1/SPL/325 .
 

Models used as follows:-

Model System Type Dial Type Colours
Telephone No. 328B Brighton BA Black, Chinese Red; Ivory; Jade Green
Telephone No. 328CB CB manual Dummy, No. 3 Black, Chinese Red; Ivory; Jade Green
Telephone No. 328F Non-director FA Black, Chinese Red; Ivory; Jade Green
Telephone No. 328L Director LA Black, Chinese Red; Ivory; Jade Green
Telephone No. 328S Siemens, Southampton FS Black, Chinese Red; Ivory; Jade Green

British Ericsson provided the GPO with Telephone No's 328F,  328L and 328CB.

Circuit diagram - N428.

Diagram for Button labels - N620.

Drawing No. 63022 - Telephone components parts.
Drawing No. 63023 - Chassis components.
Drawing No. 63250 - Chassis components (improved switch hook buttons).
Drawing No. 90373 - Chassis components (improved switch hook buttons).
Drawing No. SBA12 - 300 type base plate.
Drawing No. SCA17 - 300 type complete case.
Drwaing No. SCA20 - 300 type case.
Drawing No. SCA47 - 300 type complete case (improved switch hook buttons).

Additional good quality pictures

300 Type telephone circuit description

How to wire your Telephone No. 328 to make it work on Plug and Socket

Dismantling your Telephone No. 328

Dismantling the Handset

History, Technical and General Information on 300 type telephones

Collectors information

Adjustment of Magneto bells

Keys for use in 300 type wall and table telephones

Lamp Fittings

Labels that fit in the sliding tray

General fault finding on your phone

How to restore Bakelite

Comparison chart of GPO 300 type telephones

 


Typical 300 type chassis showing dial cord wiring arrangement


Pictures


Chassis fitted with a key unit

 

Note the model number printed on the chassis, between the bell gongs

 

 
 
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Last revised: May 13, 2024

FM