TELEPHONE SERVICES

Dominion, Volume 14, Issue 299, 12 September 1921, Page 9

TELEPHONE SERVICES

AUTOMATIC HOLDS THE FIELD OPERATIONS IN NEW ALAND Automatic telephones have come to otay, saye the chief telegraph engineer (Mr. E.- A. Shrimpton) in his report on his recent -visit to Europe and America. "Great' Britain and North America," he states, "arc now convinced that machine'switching (automatic) telephony is the only • economical system of ■ meeting the future needs of telephone service. This conclusion was arrived at in New Zealand in 1911. The engineer-in-chief and others of the British Post Office, in a recent report and recommendation to the British Government, said? 'The introduction of machine switching in telephony

is justifiable because —(a) Little or no improvement which will result in a better / or more economical service can be visualised in connection with manual exchange plant, (b) Difficulties in obtaining, training, and retaining efficient operators are so formidable in large cities that the future outlook is one of insecurity and increasing anxiety. ' (c) Tho public and Press ate demanding a bettor service. Owing to the increased cost of operating, and labour conditions generally, this demand cannot be satisfied in large cities ' under manual conditions unless . an.. .und&irablte increase in the tariff is imposed. Even then,- with the unstable operating conditions, tho attainment of improved service will be problematical. Moreover, its permanency could not be guaranteed, whereas, with a machine system a good service, once attained, would be free from 'violent disturbing influences. (d) It would facilitate the introduction of increased rates in future if the Department could allay public criticism by promising a 'grade of service superior to that hitherto given, and not inferior to thati ■ which will shortly be available in the .United States. Wo have no hesitation, therefore, in recommending the adoption of full automatic working as the only, reliable method of notably improving the telephone service." "Automatic apparatus for telephony is rapidly being standardised. The dial or sender is standardised as far as numbering and Impulses are concerned. Flaw Zealand is in an ideal position for. the , introduction of modern machine-switch-ing apparatus. We have only three of ■. what may be termed, modern manually operated exchanges—viz., Invercargill, Timaru, an 4 Hastings. The branching multiple magneto switchboards in the cities and larger towns have, in the majority of cases, reached a condition where they are both difficult and expensive to maintain. Under the conditions existing to-day in the country it will be economi* cal to instal autorafitics. in quite' small communities, especially in localities adjacent to centres where the exchanges can be unattended, only visited, at reguthr periodd for charging batteries and a little routine testing. Automatics would provide continuous service at places where the number -of lines is so small that eveii if the rates were very high the exchanges; if operated manually, would ■show a'serious loss. Even in our small localities where-we have a comparatively

large number-of party lines/automatic could be installed. The,magneto tolo- / phones on the long party lines would not v have to be changed to enable these subscribers to enjoy automatic service; dials i for calling could be attached to theymagneto telephones. The party-line sub- - ~ scribers under this system would be given individual numbers, and thus called, by automatic code ringing. The magneto ringers of these party-line telephones would be used for calling from one to another party* on the same line. This, would : avoid the necessity for placing expensive revertive ringing-apparatus in tho automatic exchanges. ".Startling ■ announcements have frequently appeared in the public Press referring "»o a sensational discovery whereby several independent telephone conversations- are possible over an existing metallic circuit without in' any way impairing the efficiency of that circuit for the purpose for which it was being used. ThO'System is known as 'multiplex telephony,’ and is brought about by superimposing a number of telephone channels wi an ordinary metallic circuit. The -underlying principles of the system are in many respects identical with those of radio-telephony,. but in adapting those principles to wire, telephony it has been necessary to carry but a vast amount, of laboratory and field research work. The. system ■ used-on one circuit in th® United States of 250 miles in length provides four multiplex channels, and . the efficiency of transmission between termin-' ale is equal to" five miles of standard cable. Tlie .articulation on these channels- is remarkably good, and the circuits are peculiarly silent. Tho special. apparatus is elaborate, and its high cost of installation and maintenance precludes its use for distances under 250 miles. For shorter distances it is at present cheaper to provide additional copper conductors, although the American engineers expect the evolution of a system requiring simpler and loss-costly apparatus. "I do not anticipate that the system will have much field for employment in New Zealand, as our distances' are comparatively short. Th& successful commercial development of the telephone repeater, with the introduction of the highvacuum three-electrode thermionic valve, will enable the more distant centres to bo provided with telephone facilities by means of a lighter-gauge copper .than hither towns thought possible. High frequency cannot as yot be used over cables, or even comparatively short lengths of covered wire, and only one set oan be used on a pole lino. , "It perhaps would not be out of place to mention here that'high-frequency carrier’ or 'wired wireless’ is looked upon by some American engij/ters as a means .of transmitting power to a distance. A light-gauge Wil's would be used from the source of the power to a point where the power can be utilised; the wire to be used merely for directional purposes, and the ethor the medium through which the power will be transmitted. We have ■ seen such startling radio developments in the last few years that I would not predict that such a dream will not come true.”