Telephone No. 17 mounted on a backboard with a bell

Wooden wall telephone with a Deckert transmitter and press button (on top of case).  The above picture shows the telephone mounted on a wall board with a magneto bell.

Used in Magneto and CBS exchange areas.  This telephone could also be used on Exchanges of the permanent current system, which uses the relay that is fitted within the instrument.

This telephone replaced the second pattern Gower-Bell telephone (single receiver) and was known as the "Telephone for Granular Transmitter 'A' (GTA)".  The "Telephone for Granular Transmitter 'A' (GTA)" was also available with two receivers.  By 1909 the telephone was called the Telephone No. 17.

Introduced circa 1901.

The Telephone No. 17 has one switch hook and one receiver, which are positioned on the left.  The above picture shows a Telephone No. 17 which only has one receiver fitted, but another can be fitted, if required, on the right hand side of the case but the hook is of the fixed type.

The switch hook consists of two contact sets;  one being a change over set and the other a break contact set.

The front of the case is removable and is fixed by means of two side mounted, knurled, finger screws which also act as the electrical connection for the transmitter.

Similar in construction to the Telephone No. 19, which has a two receivers and the Telephone No. 21, which has different gravity switch contact arrangements.

There is no bell in the telephone so a "Bell, Magneto, 100ohm" was always provided (see picture above) on Magneto circuits.  When connected to the permanent battery systems a DC bell would have been installed which operated using the relay inside the case and the batteries associated with the telephone.

Note the oval brass number plate.  Each bell and telephone carried its inventory number.  Around 1907 the Post Office realised that numbering each telephone was too much effort for too little usefulness and stopped the practice.

The Gower-Bell, 2nd Pattern, with one Receiver, was the basis for this telephone.

Telephone includes:-
1 x Coil, Inductor No. 1.
1 x Relay, Telephone, 100ohm.
1 x Cord, Flexible No. 222.
1 x Receiver, Bell No. 2.
1 x Arm, Switch, Bell, Receiver.
1 x Transmitter No. 3 (Deckert).

Superseded by the Telephone No. 21.

Circuit diagram - N117.

Additional Pictures

Telephone No. 17 with case of Ash wood



Deckert Transmitter


Internal view - Note GPO serial number


Telephone No. 17 fitted with an additional Receiver


Telephone No. 17 circuit diagram
When no relay is installed a wire link is fitted in it's place


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Last revised: December 05, 2023