SUNSPOTS

Waikato Times, Volume 122, Issue 20422, 12 February 1938, Page 10

SUNSPOTS

s TELEGRAPH EFFECTS RESULTS OF MAGNETIC STORMS The close association of abnormal sunspot activity with magnetic e3rth currents and displays of the Aurora Australis is beinc demonstrated at present in connection with the operation of New Zealand's radio and telegraphic communications. So strong are the earth currents on some occasions that telegraphic working of the normal character, utilising Hie earth u a return circuit, has been seriously interfered with. There has been no actual suspension of the busy flow of traffic—the tele-

prams handed In the quarter ended last December exceeded one and a half irth currents became s.j strong on January 17 that the Wellington Telegraph office indifferent working conditions from 10.30 am., particularly on rcuits np east to west. By 11 a.m. praeticallv every circuit was affected, even those running north and south, which is an exceptional circumstance. Advice was received at the same time from Christchurch, Blenheim and Nelson, that earth currents \vl n metallic rcuits and is not dependent on an earth return circuit, has not. been handicapped, nor is there any appreciable interference with local radio broadcasting, except that there may be occasional difficulty in securing steady reception «*f distant stations. in the short \\a\c radio Held, however. sunspot activity lias frequently caused a complete wiping out of the 31 metres Daveutry signals, forcing

j listeners to utilise the shorter waves of Ihe Empire station such as 19 |metres. The popular wave lengths for I Haventry receptions a few years ago I "'ere 25 anrl 51 metres in New ; land, but under the disturbed condii tio ns, due lo sunspots, it will i»e found that Ihe 19 metre band will generally j be more reliable.