Automatic Telephones - Introduction to Sydney
Article in "The Town and Country Journal", August 27th 1913, pages 32 & 33.
Professor Bell demonstrated at the Philadelphia Exposition in 1876 that two persons at a distance could talk to each other by means of a completed electrical circuit. Forthwith the idea of a central telephone exchange developed along the lines of switchboard connection by means of manual operators. The position the telephone now occupies, as a result of this, in commercial and public life, is a very important one. Rall as we may at its delinquencies, we dare not do without it, and demand for connection increases every day. But with the growing demand has come problem after problem, with accelerated increase, chiefly in the direction of connection, that close observers have been forced to the conclusion that telephony under the manual system has its limitations beyond which its usefulness rapidly decreases. It is now believed that no further improvements, save in details of management and discipline, can be made. But there are few circumstances in which the dictum "seek and ye shall find" does not apply. Every human problem attracts investigators, and eventually success is achieved, although sometimes long delayed, and although the reward does not always come to the first inventors.
Within three years of Professor Bell's public demonstration of the telephone, M. D. Conolly, T. A. Conolly and T. J. McTighe applied at Washington for a patent for an automatic connecting apparatus. Like many other first ventures it was not a commercial success. Others tried their hand, but it was 25 years after the Conollys and McTighe patent was registered that success seemed to be assured. A Kansas City undertaker named A. B. Strowger made application for a patent, which was filed in 1889. He was joined by a nephew (W. S. Strowger) in the following year and by Joseph Harris in 1891. The company was incorporated under the title "Strowger Automatic Telephone Exchange". The first public automatic telephone system was installed at La Porte, Indiana, U.S.A., in 1892. In that year, A. E. Keith joined the company, but for some time it only just kept its head above water. A few small exchanges were adopted in certain centres on a royalty basis, but it could scarcely be said that the system was a success. But the promoters believed in their project and in its ultimate adoption. Midst all the company's vicissitudes improvements were going on and it was becoming more and more adaptable to public needs. The Strowgers dropped out for a few years, but Harris and Keith remained and the efforts of the latter, and of T. G. Martin, W. Lee Campbell and A. E. Mellinger, resulted in great changes being made in the central apparatus. Strowger's original idea, however, is the central point of the system, and although, in 1902 a new company was formed under the title of the "Automatic Electric Company", the system which has since been such a pronounced success is fittingly known as the "Strowger System".
In Strowger's original patent, on the subscriber's telephone were three push buttons. The first represented hundreds, the second tens, and the third units. If the subscriber wished to ring up, say, 958, he would first press the hundreds button nine times, then the tens button five times and the units button eight times. Complications are obvious. Often correct count of the number of pressures was not kept and one more or one less made. Sometimes the pressure given was not enough. The main idea, still retained, was the arrangement of the contacts of the various lines in a bank or banks, each connector bank consisting of one hundred in ten rows of ten. These were arranged in the form of a segment of a cylinder. The vertical movement of a shaft connected with the various tens and the rotary movement with the units. Strowger's first patent involved five wires for each subscriber, the present automatic system needs but two.
Under the present automatic system the chief external difference between the subscriber's telephone connected with a manual switchboard and that connected with an automatic is that the latter has a dial plate in which are 10 holes a little larger than one's finger. Through these one sees a succession of numbers 1 to 0, the latter being in the place of 10. To establish communications with a number, we shall say 5783, the subscriber first takes down the receiver. He then inserts a finger in the hole which is the figure 5 on the dial, and having drawn it around to the finger stop releases it, then it automatically returns to its former position. He then inserts it in the 7 hole and moves and releases it similarly, and so on with the 8 and the 3. This accomplished, the bell at the called subscriber's end, if his line is disengaged, rings intermittantly, and continues to do so until the called party takes down the receiver or the caller puts his up. With the latter operation disconnection takes place. Should the called line be engaged the caller is notified by a buzzing noise.
In this brief article it is scarcely possible, nor is it desirable, to technically describe the apparatus by which the connection is made. What actually takes place may, however, be briefly stated. The terminals of the subscriber's lines at the exchange are arranged in groups of 100 termed units, each corresponding to a "position" on the manual switchboard. Each line ends in what is known as a line switch, and all line switches of the unit are opposite a pair of contacts connecting to what, under the automatic system, is known as a trunk. This has no connection with trunk telephone lines, but corresponds to the plugs and cords of a manual.
The action of removing the receiver from the hook automatically effects a contact between the subscriber's two lines. The caller has now exclusive use of the pair of contacts and trunk opposite which the 100 line switches were located. The 99 remaining line switches are automatically moved on to the next trunk by means of what is known as a master switch. This gaining the use of the trunk is called selecting, and the removal of the hook engages a "first selector".
As the dial springs back to its normal position it breaks the line contact as many times as the number of the cavity in which the finger is inserted. Each break of contact gives an impulsion at the exchange, and this by means of an ingenious series of armatures, magnets, pawls, springs, etc., causes a shaft to rise vertically as many notches as there have been inpulsions. This shaft is located opposite the bank of contacts. The first number, 5, is thus selected. Vertical movement then ceases and a rotary movement follows automatically. Attached to the shaft are what is known as wipers, which effect a connection with the particular pair of contacts which it is desired to engage. By the automatic rotary movement the wipers pass over any engaged trunks, reach a disengaged switch which is called the second selector.
In response to the second turn of the dial similar movements take place on a second bank of contact pairs, in the call instanced the seventh row of contact pairs being reached. Thus the second number, 7, is selected. Again the automatic rotary motion enables the wipers to reach a disengaged switch, in this case termed a connector. In response to the third movement of the dial the shaft of the connector rises notch by notch until the eighth row is reached, and on the fourth movement of the dial a rotary motion takes place step by step until the third contact on the eighth row is in contact with the wiper and direct connection with the called subscriber is established. Then the called bell rings as before explained. On either the called or calling subscriber hanging up his receiver the connection ceases.
The question now arises, what of the telephone bureau, payment for the use of which is made by inserting a coin in the slot? At present the user rings up the exchange, which calls the wanted subscriber and does not connect until the vibration of the signal advises him that the proper coin has been deposited. The interposition of the person at the exchange is here absolutely necessary, as naturally the caller is not content to pay until communication is assured. Those associated with the automatic telephone have been equal to the emergency. The bureau of the automatic system is fitted with receiver, transmitter and dial, just as in a subscriber's office. There is in addition the box for the receipt of the coin. The caller proceeds just the same as does the subscriber. He can hear the called party answer, but he cannot, owing to the vibration of the apparatus, carry on the conversation until the coin is deposited, then everything is clear. On replacing the receiver, everything is set right for the next caller.
Although the automatic system is more expensive to install, more particularly on small exchanges, than the manual, there are many obvious advantages, of which the great saving in after expense is by no means the most important. The services of the switchboard operators are, of course, dispensed with, and there are economies in maintenance, but probably the greatest advantage of all is that the responsibility of successful connection rests on but one person - the caller. The method of calling could scarcely be simpler, and if under the automatic system he does not establish the connection desired the fault is his own.
The progress of automatic telephoning since 1902 has been marvellous, more particularly during the last five or six years. Some of the latest installations in America are at 'Frisco, Oaklands, Los Angeles, Columbus, Grand Rapids and Chicago. The latter system, brought into use in 1911, is said to be suitable for a million lines. That at Los Angeles is for 100,000 subscribers. After the British Government in 1910 took over the telephone system, as a result of investigations the automatic system was installed at the London GPO and at Epsom. Subsequently Leeds was so serviced. The result has been universal approval, and further installations are probable. The Commonwealth Government has installed an automatic system at Geelong (Victoria), and so successful has it proved that during the present year orders have been booked for installations at Perth (WA), Brighton (Victoria), Newtown, The Glebe and Balmain (Sydney). In New Zealand the automatic system has been in use in Wellington since May and an installation in Auckland is approaching completion. The New Zealand installations were obtained through Automatic Telephones, Australasia, Limited, whose head office in charge of Mr. A. A. Burch, is in Sydney.
Mr. Burch has been connected with the telephone for close to a quarter of a century, having entered the service of the Michigan Bell Telephone Company at Grand Rapids as an inspector in 1889. After nine years of valuable experience in almost all departments, he became wire chief of the newly-organised Citizens' Telephone Company, of the same town, and, in 1903, was appointed manager of the Citizens' Telephone Company at Battle Creek. In the following year this company adopted the automatic system, which was continued under Mr. Burch's management until 1910, when he joined the Automatic Electric Company. In the following year he was sent to Australia to represent the company where he organised the local company, Automatic Telephones, Australasia, Limited. He is now the representative of that company, and it is under his regime that the installations in Australia and New Zealand have been and are being made.
As an instance of the rapid expansion of the automatic system, the "Automatic Telephone" newspaper mentions that orders totalling 33,300 lines of automatic telephone equipment have been received since the beginning of the present year. These orders relate to nine different exchanges, which are located in five different countries, no fewer than three continents being represented. In each instance, these installations are to replace the manual system. This means that those responsible for the orders believe that the new system has sufficient advantages over the manual to, in a short time, compensate for the loss entailed by the scrapping of an immense amount of expensive fittings. In most of the nine cases the orders are from those who have tested the system before installing it extensively, such as has been the case with the Commonwealth Government, which only began to order largely after proving the success of the Geelong installation. Many of the present telephone troubles, it is expected, will be solved by the "automatics".
From ATCS Newsletter September 1995.
Contributed by Laurie Mangleson..