J Berliner Telephone Factory


This company was started by Emile Berliner, the man who sorted out Bell's telephone and made it a workable proposition. Berliner had seen Bell's telephone in operation and set about building a better instrument that would overcome the weaknesses of the Bell . He succeeded, and filed for a patent for his improved telephone on 4 June 1877. It was a loose contact transmitter, not unlike an earlier one by Philipp Reis, but Berliner set it up so the contact was variable rather than true make-or-break. He also invented an induction coil to put into the circuit to prevent dropouts when the contacts broke apart under strong voice. The Patent application came to the notice of the Bell company and they bought the rights to the not-yet-patented transmitter for $50,000. They also employed Berliner to solve their production problems for them.

Thomas Edison filed for a patent for a similar transmitter, but his used fine carbon powder to give multiple contacts, rather than Berliner's single contact. The two patents were ruled in conflict by the Patents Office. Meanwhile American Bell had been offered a new single-contact transmitter by Francis Blake. This had been patented by Blake, and Bell decided to use it. Berliner refined it into a production transmitter.

The Directors of American Bell now set about delaying Berliner's patent. They used tactics such as taking months to reply to the Patent Office's requests for information. Their aim was to hold up the patent long enough so that when the Blake patent expired they could activate the Berliner patent and retain control of the telephone for another seventeen years. Following settlement of their legal battle with the American Speaking Telephone Company, the holder of the Edison patent application, American Bell now controlled all the important patents in telephony. They wanted to keep it that way. Berliner was frustrated at the inactivity on his first major invention, and left the company.

He went on to invent the Gramophone and to do work on early helicopters, child health and acoustics.

Although he was now an American citizen, Berliner kept in touch with his family in Germany. In 1883 he demonstrated a version of his single-contact transmitter in Austria. Interest was strong so he set up a company, J Berliner Telephone Factory (Telephon-Fabrik Berliner AG) in Hanover in Germany, to be run by his brother Jacob. The other brother, Joseph, returned from the United States to become the factory's technical director. He had spent several years studying the telephone in the Bell laboratories under the sponsorship of his brother Emile, and was a competent technician and designer. Jacob became the company's business manager because he was the only one who had experience running a business

At this point there were few international patent recognition treaties in place. Builders like Siemens and Halske in Germany and Ericssons in Sweden had been able to copy and improve on Bell's invention without patent problems. The Berliner company now also produced telephones that conflicted with the Bell company's patents. In 1893 Emile Berliner also patented a transmitter very similar to Edison's early carbon granule model.

The rather visionary German Post Office was supporting local manufacturers in this new industry. The company was able to supply parts and complete telephones and to open factories and agencies in Vienna, Budapest, London and Paris. They had to be careful not to sell into countries where the Bell patents had been granted. Their transmitters of the time are marked "Use Not Licensed Under Any U.S. Patents".

The company was renamed Bayerische Telephon-Fabrik AG (BTA) in 1918 or 1920. By this time it was starting to experience financial difficulties. After the First World War the German market was restricted due to the developing Depression and post-War punitive measures, and only those companies with overseas holdings were able to carry on successfully. BTA's other European factories and companies had been seized during the War. BTA arranged a share exchange deal with C Lorenz AG, which gave them the technology to produce the new wireless sets for domestic use from 1923. They appear to have been building wireless sets in cooperation with Lorenz, as many of their sets use a Lorenz chassis.They were falling under the influence of International Telephone & Telegraph (the owners of Lorenz) through share buyouts, and ITT was reselling Lorenz equipemnt to other makers for rebadging. It worked for a while and exports were begun.

In spite of this, at the May 1927 meeting shareholders were told that the company was in a financially weak position. The wireless factories were mostly shut down. BTA did not have the resources to take a major role in the automation of the German Post Office system, and missed out on other valuable contracts as the bigger companies and groups virtually took control of the market. By 1930 about 72 percent of the market was controlled by Siemens and Halske, and most of the rest by Standard Elektrizitatgesellschaft (owned by ITT). In 1931 the company was renamed Tefag (Telephon Aktiengesellschaft vorm. J. Berliner). It survived a little longer by concentrating on wireless sets and doing contract work for other companies like Fuld, but it did not survive World War 2.

The Transmitters

The single contact transmitter is a very compact unit, much smaller than the Blake. It could be built into a handset, and did not suffer from packing as the carbon granule transmitters did.












The later transmitter acknowledged the performance improvements of carbon granule transmitters over single-contact ones. A Marsh & Son catalog advertises that "This instrument has a world-wide reputation as the loudest and best long-distance Transmitter. The Carbon Granules resting upon the diaphragm are continually disturbed by the action of the voice, thereby preventing the Granules from becoming packed". The transmitter consisted of a top and bottom diaphragm of carbon, with the top one fixed to the case. The case was screwed together until the granules were at a suitable level of compression. Grooves machined in the lower diaphragm gave a larger surface area, which improved the signal level. A mouthpiece of black polished papier-mache fed the sound to the bottom of the lower diaphragm, and the movement of this diaphragm kept the granules from packing down.












A number of versions of the design were made over the next ten years or so. The large diaphragm gave excellent transmission compared with the Hunnings transmitter coming into use by Western Electric. The earlier version, shown at left, could be adjusted by the milled nut shown at the top. In the later versions adjustment was by screwing the two halves of the case together.


R J Chapuis "100 Years of Telephone Switching 2003"
Frank Southard "American Industry in Europe"
F Allsopp "Telephones: Their Construction and Fitting" 1897
Marsh, Son & Co "Catalogue of July 1st, 1904" London
www.radiomuseum.org website "Radio Producers - Information and history of Tefag"
"Electricity In The Service Of Man " 1886
AT&T WorldNet "Emile Berliner"
Todays Engineer, Engineering Hall of Fame "Emile Berliner and the Making of "Ma Bell" http://www.todaysengineer.org/careerfocus/may01te/may01_shorts/history_may.html
Peter Schulze "The Berliners - a Jewish Family in Hanover (1773-1943)"
United States Library of Congress, Emile Berliner Collection


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