TELEPHONE No. 3


Standard CBS No. 1 wall telephone with no magneto generator.

Wooden Local Battery telephone with sloping writing shelf.

The set shown to the right was made by Ericsson.

A later version was made, the Mark 238, which was oblong in shape (see pictures below).

This telephone was in the 1928 Rate book but not available in the 1946 Rate Book.

Fitted with a Transmitter No. 2 although earlier types had a Transmitter No. 6.

If a Transmitter No. 2 was fitted then a Label No. 78 was fitted between the speaking tube and the transmitter body.  This label advised of the Exchange name and number.

This telephone could also work on CBS No. 2 & 3 exchanges by the addition of a capacitor.

Superseded Telephone No. 15 if used with a Bellset No. 7.

Telephone No. 11 was the Magneto equivalent.

Mark 238 Telephone includes (1928):-
1 x Arm, Transmitter No. 1.
1 x Bell No. 1A, unmounted. (Earlier types had Bells No. 9A).
1 x Coil, Induction No. 1 (Earlier types) or No. 12 (Mark 238).
4 x Cords, Instrument No. 1/16E, Black, 12".
1 x Cord, Instrument No. 2/22B, Brown, 33".
1 x Frame, Notice No. 1 (Earlier types had Frame, notice, No. 2, and Label No. 53B) .
1 x Glass No. 3.
1 x Switch, Receiver No. 3.
1 x Hook, Receiver F.
1 x Transmitter No. 2. (Earlier types had Transmitter No. 6).
1 x Mouthpiece No. 16.
1 x Receiver, Bell No. 2 (Earlier types) or No. 1A (Mark 238).
4 x Fixing screws.

Frames, Notice No. 2, and Labels No. 53B, was not maintained in the old type of these instruments.

Circuit diagram - N103.

Drawing No's 8830, 8831 & 8832.

Supplied by Ericsson, their Model N20141

GPO instructions state that this telephone should be fixed to the wall with it's lower edge 36 inches from the floor.

Later version, the Mark 238
 
Inside the telephone - the silver cylindrical object, to the right,
is a modern style capacitor
 

Diagram for Mark 238 instrument
 
 
 
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Last revised: June 28, 2021

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