Radio Development

Radio Record, Volume III, Issue 25, 3 January 1930, Page 6

Radio Development

» Leading Countries Differ [t is remarkable how the practices _ of different. countries vary in the methods of radio development. One would expect that the tendencies in each country would be much the same, but such is not the case. The differences are very marked, both in relation to components and sef design. The countries where radio has developed most are Hngland, -America and Germany, and in each it is proceeding along different lines. In set design, the Germans andthe English are concentrating on small efficient sets, while the Americans are adding valves at a rapid rate. Even the construction magazines contain: descriptions of six, seven and eight valv receivers; These employ transforme coupling, single dial control, solenoid coils, band. pass fillers, and. push-pull output; they are almost invariably allelectric, using the 2.5 volt valves. All d.c. sets use 5 volts. ; The Hnglish' set is confined. to one, two, three, four, and a very rare fivevalver, resistance coupled audio, single valve output, two volt valves, basket coils, and two-dial control. ‘The battery sets ptfedominate, and there has not been. a panic through the introduction of the electric set. This has: happened in America, where perfectly good battery sets have’ been discarded, and it appears that New Zealand is rapidly following suit. Like the English, the German set is small, but in general employs transformer coupling, in conjunction with resistance. The popular set is Pe three-valver. They are not taking rapidly to the all-electric set-those introduced are employing the four-vylt valves> . A It'.is interesting to note that "different countries prefer different voltage on the filaments-England, two volts; France and Germany,-four volis ; America, five, while the ‘six-volt valve is found scattered through Burope and the Empire.