Breakthrough in Gävle
The first telephones manufactured by Lars Magnus Ericsson were copies of imported Bell telephones. During 1879 and 1880, however, he initiated efforts to design an improved telephone model. He produced a wall telephone with a so-called helical microphone that was launched in 1880. It was Ericsson's first, virtually independent design in telephony. With the new telephone, Ericsson also achieved critical success when plans were announced to install a telephone network in the city of Gävle, north of Stockholm.
In the beginning of 1881, the Bell company in Stockholm offered to build and operate a telephone network in Gävle. A competing bid submitted a proposal to use Ericsson telephones. A small number of telephones supplied by Bell and Ericsson were installed for comparative performance tests. Gefleposten, a local newspaper in Gävle, stated that both installations were extremely functional, but felt that Ericsson's telephones were "simpler, more solid and more esthetically attractive". Advisors were commissioned and they recommended the Ericsson telephones. An association called Gefle Telefonförening was established and, on February 25, 1881, a formal decision was made to use Ericsson telephones. Ericsson's victory in Gävle led to a number of consequences. It triggered the establishment of several other telephone associations and companies throughout the country, and most of them chose materials and equipment from Ericsson.
The telephone model used in 1880 featured a signal supported by batteries and a bell. In 1882, Ericsson produced an improved model with magnetic inductors in a polarized bell. The telephone had a characteristic shape that soon became known throughout the world as "the Swedish pattern".
Lars Magnus Ericsson continued to develop the microphone. After the helical microphone, he developed a simpler carbon microphone, which was patented in 1885, followed by a better version of the carbon microphone, which was patented in 1888. Another important advancement was made when the telephone receiver and microphone were combined with a handle to produce a so-called handset, which was introduced on subscriber telephones in 1892. It has been claimed that handsets were a Swedish invention, and that Ericsson was the first company in the world to use handsets in subscriber telephones. This is not true - the first handsets were designed in the US in 1878 and, after 1879, production of a handset model called combiné was started in France and gained widespread acceptance.
In addition to telephones, Ericsson also delivered exchanges to the telephone association in Gävle. In 1880, Ericsson delivered its first telephone exchange, a so-called crossing bar switch, for installation in Gävle. The single-wire subscriber lines were connected to crossing bars, and calls were connected with plugs.
Ericsson delivered a new telephone exchange for the first switching stations used by Stockholm Allmänna Telefonaktiebolag (SAT). Calls were connected with the help of cords and plugs at both ends. Each switching station had the capacity to serve a maximum of 50 lines. Using special junction circuits, telephone operators were able to connect calls between different exchanges, but not before calling out to each other, which made operations tedious and time consuming. The solution to the problem was the multi-position switchboard, which enabled every operator to reach all lines connected to the station. The multi-position switchboard was an American invention. Ericsson produced the first Swedish multi-position switchboard in 1884 for SAT's telephone exchange in Gamla Stan (the Old Town).
Author: K V Tahvanainen
HELICAL MICROPHONE FOR WALL PHONES, 1880
TELEPHONE, 1881 WALL MODEL