The competition was open to all South East Queensland H.R.S.A. Members The rules were simple, One valve, any type any number of sections in the one envelope. Performance would be judged agaist other entries with the some type of circuit, hence a superhet (yes there were two entries) and a T.R.F. would not be expected to perform the same.

With the rules in mind a decision on what type of valve to use had to be made. A battery valve like a 1D8 apparently would be judged the same as an A.C. one if used in the same type of circuit, the power supply could be mains and use valves if necessary but would be disqualified if not safe. My choice being interested in Hi-fi was a 6GW8, this valve used as an audio amplifier gives 6 Watts output for 40 millivolts input! I didn't need that much power but the gain would be useful

With this ammount of gain good results were obtained by driving the amplifer directly from a crystal set with band-pass tuning to increase it's selectivity, however the competition is held at Maleny which has no local radio stations so I decided to use the triode section in a Reinartz circuit which gave very good results.


Other considerations were:-