ONE SLIM TOWER

Evening Post, Volume CV, Issue 89, 14 April 1923, Page 11

ONE SLIM TOWER

FOR WIRELESS STATION

THE END OF A LANDMARK,

Wellington resident* have become so used to the sight of the two big masts that hold the aerial wireß of the Tinakori Hill wireless station that they will be Badly missed when, in ft few days, they are taken down for good. In their place will be used the slim and airy looking steel tower t]iat now stands between them. The present antenna ifi of the "T" type, consisting of strands stretched horizontally between the masts with a downlead from the midway point to the apparatus in the operating room. The new one will approximate to the umbrella type, which in its characteristic form has a central mast with wires sloping down towards the ground like the ribs of a. half opened umbrella,. ' The new aerial will have only four wires, two leading northwards and two southwards, so as to form a narrow cross. They will be held at the outer ends by towers varying from 20 to 40 feet in height. The central tower, which is now completed, is 165 feet high, and is a selfsupporting steel lattice structure resting upon four concrete foundations. The smaller towers will be tubular. Only sixten working days have been occupied in erectinp the central tower t and the work, carried out by the supervision of the District Telegraph Engineer's branch, has thus Jaeen done in very good time. It is expected that the smaller towers will be erec.ted ia a few days, and that the whole antenna will be completed and in use, and the old one demolished, in a week or co, unless bad weather causes delay. The reasons for • changing the aerial are chiefly mechanical. In the first place, the wooden masts, a.fter many years of service, are showing signs of age, and the choice of the umbrella type is.dictated by the fact that there will be only one big mast to keep" in good condition instead of two. Electrically there will be no great advantage. The numerous steel stays of the wooden masts absorb an appreciable • amount of the transmitted energy, and as the tower has no stays. this loss will be cut out. On the other hand the steel tower itself will cause some loss by absorption, though it will be reduced to some extent by the insulation afforded by the concrete foundations. On the whole the electrical advantage is considered • to be with the new aerial.

A .corespondent who describes himself as "engaged in the trade and a New Zealand taxpayer," writes asking if it is time that the tower was bought from a New York firm, and if so, whether New Zealand or British makers were given an opportunity of 'tendering for the work] The matter was referred to the Post Office' authorities, and it was officially stated that the tower is the manufacture of an American firm of specialists jn. steel tower construction. As is usual in such matters, quotations were called from all likely manufacturers who were qualified to construct a tower of suitable design and strength. The Amerioan firm referred to" was' hv f ar the lowest tenderer ,in the United States, and Great Britain, and consequently its tender was accepted. • "■•.'.