|Battery Ringing Telephones
N 1181 shown in both pictures.
These wall sets are similar in principle to the N1200 series table telephones and are designed for railway signal cabins, etc., where an efficient and robust instrument is necessary.
The hardwood case is semi-matt polished and the exterior metal fittings are black and bronze.
Instruments with one, two or four plunger keys can be supplied, the illustration showing a 4-key set modified for 2-key working, the inner ones being shrouded. Key springs are wired in the set to terminals which can be strapped to suit various operating requirements.
A high, medium or low tone dome, as specified on order, is fitted on the 100 ohm bell which, in the N1183 type sets, is directly operated and in other sets is actuated via the contacts of a 5000 ohm polarised or non-polarised relay. A differential relay can be fitted, if necessary, an extra wire being included for this purpose.
The instruments contain a 2 mf. condenser for the receiver circuit, anti-side-tone induction coil, hook switch and terminals for wiring a remote bell if required. The Bakelite micro-telephone can be supplied with or without a transmitter cut-off switch in the handle, as indicated in the table below.
Overall dimensions 9 x 11 x 5 inches.
Last revised: June 23, 2020