This is one of the most robust, powerful and compact portable magneto telephones specially designed for use in the field, as a linesman's testing set or a temporary station.
To provide protection against rough usage and weather the cover is constructed of light-gauge steel, partly pressed up and partly fabricated by welding. The various parts are thoroughly cleaned by shot-blast, rust-proofed, and finally treated with a hard-baking synthetic stove enamel. Attached to the case by swivel links there is a strong woven-fabric shoulder strap provided with adjustable buckle fastenings and loops for carrying an earth spike.
In the illustration. the lid of the set is open also the lid of the battery compartment, the micro-telephone removed and the micro-telephone plug inserted in the jack, the generator handle, which is normally stowed vertically between the protecting projection seen at the right hand side of the lid, is turned down at right angles and automatically held in that position; to replace this there is a spring loaded slide provided on the crank. As the micro-telephone is provided with a press key for closing the battery circuit it is important to remove the plug from the jack before packing up and closing the lid, thus ensuring that the battery will not be run-down inadvertently.
The main apparatus comprises a micro-telephone N5871, "Alnico" magnet generator N4644, 1000 ohm magneto ringer N3110T, anti-side-tone induction coil N3533T and 2 cells N3767. The generator has an output of approximately 3 watts.
The codes of the parts most liable to damage are:-
If desired this instrument can be supplied with a 2 mF Condenser in the ringer circuit; Code N1843A.
The instruments are suitable for use in tropical climates.
Taken from the Ericsson Telephone Catalogue, edition No. 26, Supplement 1935
Diagram N15924 dated 1932
Last revised: June 22, 2020