TELEPHONE TRAFFIC

Dominion, Volume 29, Issue 299, 14 September 1936, Page 6

TELEPHONE TRAFFIC

New Cable For Cook Strait READY NEXT MARCH The announcement that the Post and Telegraph Department has accepted the tender of Submarine Cables Limited, London, for the manufacture of a new cable about 38 miles long specially designed for telephone communication across Cook Strait was made by the Postmaster-General, Hon. F. Jones, on Saturday. The contract time for completing the manufacture of the cable is next March, when it will be shipped to the department’s cable stores in Wellington and laid by the cable ship Recorder on a route from Lyall Bay to Blind River near Seddon.

“Telephone business between the two islands,” stated the PostmasterGeneral., "has grown at a remarkable rate until it has practically reached the full capacity of the existing channels, although modern development in connection with high-frequency eerier currents enabled a great deal more work to be carried by some of the older cables than was actually practicable when they were originally designed and laid. The present crossstrait communications are provided'by one four-core ‘loaded’ telephone cable (enabling four conversations to be conducted simultaneously), and six single-core telegraph cables. These seven cables yield a total of six tele-* phone channels plus four single-wire machine-printing telegraph circuits. "It is necessary to provide for rapid advances in business and a good margin for contingencies, and this Will be amply covered by the capacity of the new cable, which is. of the single-core

coaxial type similar in general characteristics to that recently laid by the Commonwealth Government across Bass Strait between the mainland and Tasmania. It represented so important an advance in communication across Bass Strait that the Commonwealth Government signalised it. with the issue of a commemorative stamp. The cable has been very successful in its operation, giving five telephone channels and eighteen telegraph circuits simultaneously, a notable advance in the technique of submarine cable construction. “The new Cook Strait cable will have a central core of copper' surrounded by an insulating medium recently developed, known as paragutfa. Spirally wound over, this will be several copper tapes, then a layer of jute, over which is placed the outside protective covering of heavy iron wires. ( This type of cable is specially adapted for the use of high-frequency current, and it will be practicable to operate simultaneously twenty-five carrier current telephone channels (enabling 25 conversations to take place), and in addition, it. can be used at the same time for eighteen two-way teleprinter, telegraphic channel*.”