Pupin Load Coils

[Trade Journal]

Publication: Western Electrician

Chicago, IL, United States
vol. 32, no. 11, p. 209, col. 3

Pupin Telephone Load Coils.


Mention has already been made in these columns of the experiments conducted on telephone circuits near Berlin, Germany, to determine the advantages of applying to the lines the inductance or load coils which have been invented by Professor M. I. Pupin and which are used in this country by the American Telephone and Telegraph Company. The Germany experiments showed that by the application of Pupin's system, an underground cable with a conductor of one millimeter diameter could be rendered equivalent in speaking capacity to an ordinary unequipped overhead wire of two millimeters diameter, or four times the section. The arrangement of the inductance coils was very simple. Each set of 14 coils of annular cons