AUCKLAND TO BLUFF

Evening Star, Issue 18669, 25 June 1924, Page 3

AUCKLAND TO BLUFF

NEW TELEPHONE ERA. SUBMARINE CABLE AND BELAYS. [Special to toe * Star.’] WELLINGTON, Juno 24. Tho announcement that tho Post and Telegraph Department will lay a continuously loaded cable for telephone purposes across Oook Strait gives promise of telephone communication from Auckland to tho Bluff, not by dint of superhuman power of speech, but actually with at least the wise of intercommnir.iaition between subscribers of the same exchange. This is to be made possible by tho adoption of tlw electrical relay, which has maclo long-distance telephoning possible. Hut for this invention, for which tho requirements of wireless have mainly to bo thanked, it would bo impossible to carry on practicable commercial speech over such long distances. Tho limit under ordinary conditions is expressed in engineering terms as about thirty-fire miles of standard cable. Tho circuit between Auckland 1 and Wellington is equal to fifteen miles of standard cable; from Wellington across the Strait to tho beach near Mcddnu (where the cable will bo landed) means twelve miles of standard cable: tbenco to Christchurch .another twelve miles; Christchurch to Dunedin ten miles; Dunedin to Invercargill seven miles. 'lbis provides a total for technical purposes of fifty-six miles, which would completely pur, out of Die question telephonic speech between Auckland’ and the Month Island; hut by means of the relay instruments weak circuits arrive at a point at which they receive an impulse amplifying tho original. This process can he repeated wherever the impulse drops below the point at which the telephone users would have difficulty in hearing each other. One relay between Auckland and Wellington would make telephonic speech as easy as over seven or eight miles of standard cable. Other repeaters in tho Mouth Island would act with equal efficiency in !*>osting up the original speech impulse, with the result that conversation between Auckland and Invercargill woidd bo as easy as that conducted over twelve miles of standard cable, though commercial speech is possible over thirty-five miles of such a cable. PROFITABLE WAdTIXY!.

It is on record that tho tclephouc clivi-' sion, by waiting a year or so before letting (lie contract fur the .Dunedin Telephone Exchange, saved £10,003, and that almost a similar amount was saved on the Wellington Exchange contract; but an even larger sum is likely to be gained to the dominion through the decision of the chief telegraph engineer (Mr .Shrimpton) three years ago in recommending the rejection of tenders for a continuously loaded telephono cable for Cook Strait, the drop in prices having been enormous. Tenders aro, being called immediately, and it is anticipated that complete telephone intercom.monicai.ion in the •dominion from north to south will bo in operation by February next. The relay system will benefit not only the route described, but every other long-distanco circuit used by subscribers. The West Coast will be able just as easily to fall; with the North Island as with Christchurch., possibly easier, when the electrical relay is introduced into the circuit.

When extremely high prices were quoted for the special class of cable needed fbr Telephone purposes across Cook Strait the department considered a wireless scheme for bridging the gap, connecting with the ordinary land linos; but the groan reduction in the prices of cables makes wireless more cosily and Jess cliictcnt than what is to be. installed.