Answers to Correspondents

Radio Record, Volume III, Issue 42, 2 May 1930, Page 30

Answers to Correspondents

struct "Round-the-World"’ Tw but asks further information on severg/ points. : 1: Would a five-plate neutralising conGenser be all right in the aerial lead ?-~ 2: Instead of the ’phone jack, could I use jack with four contacts and do away with the battery switch by connecting the top prong to A and B-, the second to the secondary of the transformer, the third to P of the sound valve socket, and the last to B+? A.: Yes, the second connection goes to the secondary of the transformer and then to the negative connections of the valve, If grid bias is required, the connections shown in the 8-yalve set de-_ scribed in the following week’s issue must jack, it is shown as jack No. 2 in the accompanying diagram. 8: I intend to use Radiotron 24 Li "H. J.C. (Wellington) wishes to detector, and Philips A609 as audio ™¥ ill these be all right? A.: Yes, but if you are purchasing new valves, use the new Radiotron 221, as it is very similar to 201A, but requires less filament current. . 4: Will an amperite be necessary for the audio valve if I use a 6-volt accumulator ?-No. 2