WIRELESS DEVELOPMENTS

Stratford Evening Post, Volume II, Issue 224, 20 April 1933, Page 3

WIRELESS DEVELOPMENTS

Tremendous Progress Made

Press Association —Copyright

London, April 10.—So many astonishing wireless developments have occurred in the last few months that the technical journals complain of the d’lßcultv of keeping abreast of them. The discovery of a quiescent pushpull which gives an output from battery sets equal to that obtained from electric sets, recently hailed as revolutionary, is already superseded by the invention of a “Class B ’ valve that costs 14s This, with a 120-volt battery current, gives fully two watts of undistorted output, sufficient to fill a concert hall, whereas even the largest sets operated from electric mains are capable of only l.i. watts. The new valve, in spite of its power, uses less current than ordinary

valves. . Now ferrocart coils, with a coil ox finely-divided iron, give astonishing selectivity equal to the superheterodyne. . , Another important development is the Westector rectifier, composed of discs treated with copper. This gives fine selectivity, combined with considerable distortionless amplification. Experts consider that the combination of these three developments will make existing sets obsolete.