"ALL ALONG OF DIRTINESS "

Evening Post, Volume CXV, Issue 103, 4 May 1933, Page 19

"ALL ALONG OF DIRTINESS "

Many handbooks on radio apparatus contain • elaborate directions on the location of various kinds of trouble in receivers; but the majority of modern sets are hardly of the kind which the average owner can explore and test bit by bit. • Many- of thorn cannot be got into at all without almost destructive tactics. However, troubles are sometimes caused by defects in places that can be .reached, and an interesting case of the kind was run into recently, in a set which produced a, very'noisy, irregular crackling noise. The first test in. such cases is always the aerial system, mainly because it is easily detached and is a common source of such noises. In this case, the detachment of the aerial immediately reduced the noises—in frequency, but not in character _ or strength. Precisely the same noisesj continued, but much less often. Itieconnection of the aerial restored the number; and' the desturbances then seemed to -coincide, in some measure, with the gusts of the high wind then blowing. It was known that th'o far end of the aerial was just' within reach of an overgrown branch of a neighbour's blue-gum tree, and that the leaves (wet at the time) might be just sweeping the aerial. This was therefore accepted as the probable cause of the portion of the troublo which was removed when the aerial was disconnected. The rest of the noise was luckily found without much trouble, in a place where it may often be found—a dirty contact in the detector valve socket. ■ Socking the valve in its socket reproduced the noises in fine quantity. That, of course, was soon remedied, and tho Bet was left! working, -with plenty of noises coming in from' outside. But' theso. actually* got worse, - and at timos tho i set became very insensitive. On the .following day, when.1 it was quito calm, there was no question about the interference being due-to fho tree; it was not guilty. But the noise had dihnppciiTorl completely, leaving the rcccivci- h(ill insensitive. It seemed pro-. li.-iMc Hint as the loss of sensitivity, had been closely associated with the noises, and ulso that tlio noises, had been duo to tho wind, the aerial was i in some way to blame, and the matter was investigated by daylight. It was jthen found £hat S&S Jroublg jvaa duej

to the connection of the down leacU from the aerial to the lightning arrester. The nut, which was a lightfitting one, had not been screwed down sufficiently hard, and the down lead had gradually worn itself a small amount of play. Long exposure of the joint to air and. moisturo had produced a little oxidation which was sufficient to insulate the wire in certain positions. This was cleaned and the nut properly screwed down, and everything was promptly in good order again. Two scraps of dirtiness —and n household in revolt! \

Mr. Lenhart Bernadotte, the former' I'riiicc Lennart of Sweden, who gavo up his title when'he manicffMUs Karin Nissvandt in ■"London last year, has changed his plans to become,a ladio announcer and is iiow negotiating with the Swedish Broadcasting 'Company ior a post n& editor of its sketch, rdepartment. The ox-prince, wJio has an income of between and £6000 ;i j'car, has speitt much time sineo' his mairiage -in- writing and. has also composed a i'evue.'