TELEPHONE, OBSERVER, D.C. SIGNALLING AD599
An unusual telephone as it has an indictor which operates a DC alarm bell.  The bell can be switched of by means of the tumbler switch.  There was no handset with this telephone and it was supplied with a transmitter and headset.

The telephone uses two wires and an earth connection.

The Indicator is operated via a battery on any line wire to earth.

There are no switch hooks as the transmitter has a switch on it's body.

Diagram No. AD 599 (Dated 1940).

Telephone includes:-
1 x Coil, Induction No. 12.
1 x Jack No. 3.
1 x Plug No. 404.
1 x Bell No. 65A.
1 x Cord Instrument No. 4/61KB.
1 x Cord Instrument No. 2/69K .
1 x Cord Instrument No. 2/90K.
1 x Condenser No. 97.
1 x Generator No. 26A.
1 x Indicator No. 2200A.
1 x Receiver Headgear No. 10A double.
1 x Rectifier Element No. 1/12A.
1 x Switch Tumbler.
1 x Transmitter No. 23.
1 x Transformer No. 48A.

 

 

 

 

 
 
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Last revised: November 27, 2023

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