This field telephone was manufactured by, or on behalf of, "Wyssen Seilbahnen" in the early 1950s. This particular unit likely dates from 1955 to 1956, based on the date stamped on the Leclanché capacitor.
The instrument may have been used in cablecar maintenance or repair contexts to facilitate communication between the base and top stations, or possibly as a temporary installation at these locations. Since "Wyssen Seilbahnen" still operates today, I plan to reach out to them to inquire if any historical records or specific details about this instrument are available.
Universal battery compartment which accepts either a 4.5V lantern battery or 2x 1.5V D cells.
Ready for use
Disassembled
User guide and wiring diagram inside lid. The plate made by Aloxyd AG is signed with a date of Nov. 30, 1949, probably the year of development/release of that instrument type.
Standard Swiss Modell 1931 handset with P.T.T. On TX side adaptor to fit newer Type 1946 elements.
RX element opened. RX elements of this type exist sealed and to open. If the to open once can be opened to exchange diaphragm or if it is just because of mfg. process is unknown to me.
RX element type 1931, mfg. by Gfeller, TX element type 1946, mfg. by Zellweger.
Battery compartment, Ringer bells and indicator, Coil, Generator. Ringer and Coil are mfg. by autophon, Generator seems to be of british make.
Capacitor on top of generator. Lightning arrestor on right above battery cup.
Date on Leclanché capacitor suggests an instrument mfg. date of 1955 to 56.
Empty box, generator crank hole in bottom.
Handset and crank handle stowed..
Read for transport or storage.
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