When it arrived, the 500-switch automatic telephone system was a mechanical marvel, capable of handling a whopping 500 lines. Imagine electric motors propelling selectors in a dynamic dance, with a wiper arm executing both circular and radial movements to navigate the contact fields and wires. (For a better visual, check out the short video showcasing its action.)
The initial idea came from an Ericsson customer. Axel Hultman, director at Televerket, Sweden's PTT, had for years tinkered with automatic switching at the public telegraph service. Ericsson was a leader when it came to manual switching technology – think operators moving phone lines at a desk – but the company grappled with competitors in automatic telephony. Hultman, moonlighting as a private visionary, inked a game-changing pact with Ericsson in 1913. The dynamic trio of Hultman, and Ericsson engineers Martin Löfgren and Sigurd Johanson, nurtured this brainchild to fruition.
The first 500-switch stations were placed in operation in Rotterdam in 1923, followed by Stockholm the year after.
Another Ericsson innovation from the era was the Bakelite telephone, unveiled in 1931. Celebrated not only for its avant-garde design but also for its revolutionary anti-side tone coupling. Previously, the microphone picked up speech signals and background noise that could affect the receiver. The introduction of a differentially coupled speech transformer significantly reduced interference from the microphone, resulting in a noteworthy improvement in speech quality.
Also: the fallout of the Kreuger crash
In the mid-1920s, the Swedish business giant Ivar Kreuger started buying large ownership stakes in Ericsson, as he had in many other Swedish companies. Kreuger was at top of his empire-building days – but soon realized he had overextended. He entered discussions to sell Ericsson to its US competitor, International Telegraph & Telephone (ITT), and in June 1931 ITT in fact became majority owner of Ericsson. Ericsson was lined up to become a subsidiary of ITT. But then things took a dramatic turn. Ivar Kreuger was found dead by a gunshot in a Paris hotel room in March 1932 and his entire empire crashed.
Even more: the LM city
By the mid-1930s, Ericsson had outgrown its premises at Tulegatan in central Stockholm. In 1936, it laid plans with architect Ture Wennerholm and Ericsson’s head engineer Olof Hult to build a gigantic industrial complex just south of the city.
This complex consisted of two parts. One was a low production facility for heavy manufacturing, a 14,000 square meter hall with sawtooth roofs and sky lighting. The other was a four-story building for offices and lighter manufacturing.
Architecturally, Ericsson's manufacturing complex became admired internationally as an outstanding example of Swedish functionalism and, even more perhaps, as a well-conceived production facility according to the Taylor school of operations.
The project also included the development of a residential area with apartment buildings surrounding the square Telefonplan (“Telephone Square”), a name inspired by Ericsson’s operations.