Unnumbered Page Advertisement 1

Radio Record, Volume V, Issue 15, 23 October 1931, Unnumbered Page

Vowll find Hhis screen-grid valve is bettew Jhe OSRAM My 224 6' 0 MADE INJ EMGLANE PEREECT radio detection is a matter of perfect valves. This new 2.5 volt Osram is, like the entire 2.5 Osram series, definitely non-microphonic: Shocks or vibration do not affect it. It is the ONLY screen-grid valve thac is perfeccly noiseless in operation: You cah test Osram 2.5 at Your Radio Dealer's_ Ask to switch on any set, tune sqeecicritY out stations and tap the 224 or 227 detector. If it is microphonic the speaker will emit 3 Pinging noise, indicative of imperfect reception: If the micro- phonic valves are replaced by Osram 2.5s, tapping will result in silence: Ask Your dealer also to show You the full range of Osram 2.5 volt valves 9558 MXzs 8 MXz8a 25e MADE IN ENGLAND Advertisement of the BRITISH GENERAL ELECTRIC CO_ LTD_ 37 Taranaki Street; Wellington. Brunswick Bldgs , 49 High Street, Auck-land. Hannaford Chambers; 145 Worcester Street, Christ- church: