Questions and Answers

Radio Record, Volume IV, Issue 23, 19 December 1930, Page 30

Questions and Answers

"LitfLe WILLIE" (Gore): Would the Loftin Four be superior to the H.R. Four? A.: There is simply no comparison. The Loftin Four stands supreme. It is the last word in modern sets, 2. Would a five-valve s.g. Browning Drake be a better choice than an H.R.4? Yes, Than the Loftin Four?-No, . Is a set using accumulator valves and A and B eliminator superior to the same type of set using a.c. valves? A.: No; the a.c. set has usually a far greater voltage available than has the d.e. set, consequently it gives better results. . . 4, Can a license be for one month for a portable set? A.: It will cost you 2/6. J S. (Wellington): What is the gauge © of the wire I enclose?-24 d.s.e, 2. What alterations are necessary in the coils of the L.W. to accommodate .00035 condensers?-See constructional article this week. 8. Can I use the 24 dis.c. wire for the primaries?, A.: No; it will take up too much space, Wit (Timaru): Will a counterpoise improve my set? A.: It will weaken signal strength but should minimise interference. 2. Please explain exactly what a counterpoise is. A.: It is another aerial slung directly underneath your normal one. It should be insulated just as carefully as the normal aerial and should be high enough to clear the ground. It is taken to the ground aerial of your sev. 8. What would be the cost to build the a.c. short-wave adapter described in the 1930 "Guide:" A.: Using good components, about £5. Ko (Timaru): Would you ériticise the enclosed circuit of a portable. A.: We think you would he troubled with hand capacity. The moving plates

of any reaction condenser should be connected to earth or to the lowest potential. The fixed plate going to Ashould be the moving plate, and _ the moving plate should be connected with eart. 2. What B battery would be suitable? A.: Write one of the big city dealers who could no doubt tell you something about it. ¥ 8. Is the valve combination correct?es. AX ¢ (Dunedin) + What are the correct for the following ! 4.809 r£., A615 detector, ay We af and B605 power? A.: ith A609, 60 volts, no OA 45 volts, with a positive grid return, first audio, 90 volts, 3 volts bias; B605, 185 volts with 124 grid bias. 2,’ Where can I get particulars of an efficient wave-trap? .: There is a good one in the 1930 "Guide," and another will be shortly appearing in the "Radio Record." 3. What waveband do the Ameri and Japanese stations use, and whr the best time to get them? A.: We published those facts only a couple of weeks ago. The American sta~tions operating on all broadcast wavebands can be heard in the later afternoon or early eveuing, and the Japanese stations.after 9 or 10 o’clock. 4, What is the cure for slipping ver: nier dials? A.: Tighten them. If you cannot do this take them to a dealer,