INVISIBLE SERVANTS

Wairarapa Times-Age, 27 November 1939, Page 7

INVISIBLE SERVANTS

A FASCINATING EXHIBIT. One of the most fascinating exhibits in the Government Court at the CenI tennial Exhibition is the radio section lof the Post and Telegraph Department’s display, which includes several modern wonders of science adaptable for domestic use. This section includes devices by which a bell may be rung merely by waving the hand; a telephone dial, which will set all sorts of domestic electrical appliances in operation. by the twirl of a finger; and a machine which enables visitors to look at the sound of their own voices on a screen. The magic dial, as it is called, demonstrates the use of ultra-short radio waves for communication purposes; a radio set, electric .lights, and other apparatus may be set in operation by the dialling of their particular number. The telephone dial, which is mounted on a small box, may be carried around within the borders of the stand, and in the home it could be used in any part of the house for turning on an electric stove, water jug. radio or toaster. The fascinating possibilities of the magic dial are impressed on visitors, who leave the stand with rosy visions of setting their coffee pots and toasters and wirelesses in operation in the morning by dialling from their beds without having to go to the I kitchen. The box, with its magic dial is an ultra-short wave radio transmitter. which transmits signals in accordance with the number indicated by the dial. There signals are picked up by receiving sets. which, in turn, switch on the particular device.