In 1900 the Berliner
Telephone Factory of Hanover, Germany established a factory in Britain
to take advantage of that country's rapidly expanding market. Shortly before
World War 1 the factory was renamed The Sterling Telephone & Electric
Company. This may have been a reaction to the changing political situation
in Europe, when it seemed a war between Britain, France and Germany was inevitable.
Sterling was an early starter in the days when electrical devices were a new
growth industry. They seemed to have had most success with their range of
small intercoms, and many collectors will have at least one Sterling phone.
Little is known about their management after the change of name, but there
is no doubt that they were well-financed and well-run. One of their major
customers in the earliest days was Britains National
Telephone Company. They supplied the National with a wide range
of their CB desk phones and intercoms, and some of their specialist lines
such as mining and tramway phones. The telephones were built at a factory
at Dagenham that they bought from Morris Arming Tube and Ammunition Company
in 1910. They set about enlarging the factory to handle woodworking, ebonite
moulding, metal turning and electrical wiring. The factory covered more than
four acres by the end of 1910, and was increased gradually to ten acres.
Their catalogues show that many of their early phones were partly built with components sourced from the Swedish manufacturer L M Ericsson and from their Berliner parent. . This was a common practice for many telephone manufacturers at the time. During the First World War, these were replaced by Sterlings own parts. Prewar they also bought in complete phones from Berliner, Alfred Graham & Co, Ericsson and Western Electric and simply rebadged them. Finally, postwar they dropped much of their early product range and produced phones to the British Post Offices standard patterns.
Sterling was a general electrical manufacturer rather than a specialist telephone producer. Their range covered phones, switchboards, and electrical and telephone equipment and fittings. From early days they also developed wireless sets to service Marconis new invention. During the First World War Sterling wireless sets were installed in Royal Air Force spotter planes. They continued this development after the war and were eventually part of the founding group of the British Broadcasting Company , the BBC.
They seem to have been able to market their telephone products quite successfully overseas but this was usually done by a local distributor rather than by Sterling themselves. Relying on others to sell your product is a dangerous marketing move. It was in this that they lost out to the better organised companies like GEC and Ericssons who established direct marketing offices in many of the British Empire countries to secure their markets.. In the end, the sale of the Sterling company to Marconis commercial radio company Marconiphone meant the end of telephone manufacture.
Sterling telephones fall into four main groups:
The first group is phones for the public network. The wall phones show a certain individual style, resulting from the use of common components assembled in different configurations. Sterlings Model U262 long-distance phone is a good example of this. The small box that contains the electronics is used in many other models. The desk phones show more variation. The Model U385 is an Ericsson A300 tin box style base fitted with Sterlings straight-armed cradle and their own handset. The Model U716 also used their handset on a modified candlestick-type base. They seem to have preferred handsets for their exchange telephones, but later they had to go back to the separate transmitter/receiver style when they produced phones to British Post Office specifications. These specs were based on Western Electric phones that had proved reliable and compatible with the WE switchboards in wide use in Britain.
The second and largest group was the Interphones, particularly the Primax models. Today these would be called switchboards. Many of these are the old Berliner designs. Early models were fairly basic and had no secrecy on calls. For this reason they were generally controlled by a single person such as the manager. One-way signalling, main to extension only, was standard. The Model U2115 is an impressive example. Note that it is based around an Ericsson-style miniature phone to handle the electronics. The Model U410 is a familiar intercom that is present in many collections. The extension phones for these systems had incoming signalling only and no automatic cutoff - this was handled from the switchboard. The Model U125 is another familiar example of this style of phone. As the internal use of telephones grew, the Reply and Call system was introduced. This allowed extension phones to call back to the main switchboard as well as receive calls. The extension phones of this system are identifiable by the small signalling pushbutton built into the phone, as seen on the Model U505. Model U310 is another distinctive little phone of this type, with its sloping front and rear-mounted bell. Switchhook hangup also came into use around this time. Later, secrecy between calls was introduced as well so multiple calls could be handled at the same time. These systems were not connected to the public network. In spite of the amount of cabling required they were a very popular type of phone system.
The third group was the internal point-to-point intercom, also called House Phones. The Parleyphone range is typical. Model U61 is an early example. They were basic, mostly consisting of a wall terminal block with a pushbutton for signalling to the other phone, and a suspended handset. On the more elaborate models two-way signalling could be provided, and for the really adventurous a two-extension model was available. Again, mant were Berliner designs. The Parleyphones and other intercoms were widely sold in Australia by firms like Anthony Horderns and Warburton Franki. It is interesting to note that when the British Post Office took over the National Telephone Company they kept these house phones in use for some time. Handyman books of the time show enthusiastic homeowners how to convert their internal bell signalling systems to telephone. Many of the phones could be used on the bigger intercom systems as well, and were fitted with a pushbutton for signaling as Reply and Call came into use. Model U305 is a good example this simple little wooden box desk phone was introduced in the 1890s with Ericsson cradle and handset, was upgraded to the Sterling cradle and handset around 1910, was fitted for Reply and Call and became Model U510, then was built into a steel case in the late 1910s and became Model U306.
A fourth and lesser-known group was the Phonopore models. These were specially designed phones that could handle voice work across morse telegraph lines without interference to the Morse signals. As such they appealed to railways worldwide. They could reportedly carry a signal for more than a hundred miles and appeared to be free of induction and lightning strike problems. Sterling bought out the Radio, Phonopore and Electricals Company from Mr C Langdon-Davies, the inventor of the phone, in the very early 1900s and kept the range going until the 1920s. Because railways workshops tended to keep repairing and modifying phones long after their usual working life was over, an original Phonopore is hard to find. In Australia, the last one was taken out of service in the 1950s. Similar phones were made by Ericssons and others.
Sterling also had a range of specialist phones such as linesmens test phones, miners phones, and ships phones. The Model U574 is a ships phone from Alfred Graham & Co for use in noisy locations like enginerooms.
Sterling made a small but useful range of magneto and CB exchange switchboards
as well, but they do not appear to have sold these in great numbers. They completely
missed the potential of automatic telephony, or more likely did not have the
research and development staff to exploit it. It is also possible that their
attention was diverted by continued development of wireless. After the war they
found their sales of telephones were confined to a small portion of the British
Post Offices needs, and there was no market for their telephone exchanges.
They diversified into newer types of electrical gear like headphones (radio
head telephones), but they could not compete with larger companies like
Britains General Electric Company.
In 1926 they sold out to Marconiphone and the factory was turned entirely to production of Marconis valve wireless sets. The GEC company picked up what was left of Sterlings telephone business. GEC had been selling Sterling phones for some time, rebadging them with GEC model numbers. For some years the Sterling factory was quite successful in its new field. The complex was enlarged to eighteen acres by 1925, with its own power station, gasworks, printers, fire station, first aid service, canteens, recreation hall, and undercover storage for seven hundred staff bicycles.
Over the years, production needs changed and the huge estate and factory complex was broken up and sold off. In the 1970s Ford bought about a quarter of the complex as an assembly line for production of the Ford Capri. The Sterling name remained, however, and kept turning up in unexpected ways. As an example, one of the engineering plants on the estate produced the Sterling submachine gun during World War 2 for paratroops and commandos.
There are nearly a hundred different phones shown in the catalogues available to me. This shows that Sterling was not just a small maker of intercoms, but a major manufacturer in the early days of the industry. In Australia we mostly see their little intercom phones, and I think they are greatly underestimated because of this.
Wedlake G E C SOS The Story of Radio Communication Melbourne , 1973
Sterling catalogues : various
Plessey Company History, http://strowger-net.telefoonmuseum.com/
Bateman J History of the Telephone in New South Wales 1980
General Electric Company Catalogue 1935
Freshwater Bob Website Telephone File http://web.ukonline.co.uk/freshwater/sterling/ster1.htm
Howson J. Dagenham and Broadcasting , undated. Courtesy Dagenham Historical Society.
Dargan James Morse to Micro - A History of NSW Railways 1988 Sydney