Page 6 Advertisement 1

Radio Record, Volume IV, Issue 39, 10 April 1931, Page 6

THE DIFFERENTIAL FOUR That extra stage will make all the difference to your results. It will not be_ ~expensive to add either: Look at thege Prices Transformer .10/6 Ferranti AF 4 81/3/- Valve, we recommend B405 for greatest slift" and output :15/- Valve Socket 1/6 Anti-motor boating device, 600 ohm resistance and 2 mfd; condenser 6/6 400 ohm Potentiometer 5/6 Send for our Price Ligt: AII Postage Free. ~HP CAs; (Country Accessories Supply) 2 VENINOR STREEE, SEATOUN, WELLINGTON