Battery Ringing Telephones
For certain positions in railway signal cabins a wall type telephone is sometimes more convenient.
This instrument has therefore been specially designed for durability, simplicity and efficiency, in such service.
The case work is made of oak, polished to give a semi-matt finish and the exterior metal fittings are black and bronze.
The efficiency of the Bakelite micro-telephone is of the very highest for both reception and transmission, and the provision of an anti-side-tone induction coil is a further improvement in reception qualities.
The N1174 instrument is fitted with a 2-microfarad condenser in the receiving circuit; other values can be supplied, or instruments without condensers, in the latter case the wiring is so arranged that a condenser can be added at a latter date if required.
The other interior fitments are a hook-switch, ringing key with press button outside and relay which operates with weak currents and automatically connects a local circuit for ringing the bell. The relay resistance is 5000 ohms. and the bell can be fitted with high, medium or low tone dome. The tone of dome must be stated when ordering.
As well as the usual terminals for line and battery connections, a pair is provided for connecting up an extra receiver.
Dimensions 12 x 10 x 4 inches.
Click here for a blueprint picture of the N1174
Last revised: November 27, 2020