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Radio Record, Volume I, Issue 28, 27 January 1928, Page 5

'A Melbourne amateur transmitter writes in the Melbourne "Listener In’: There are rumours travelling round amongst the hams that the average short wave receiver does not respond to signals as well on 20 metres as it does higher up, and from mv results and experiments on from 5 to 10 metres I can quite believe it. "For those who are trouble hunting down there I would suggest that the best thine to do is to start off with moving coil reaction and a home-made tuning condenser. This condenser need only consist of two nlates of standard size, one fixed and the other soldered to a niece of quarter-inch diam brass rod. This rod can then be mounted in bakelite bearings, and a pigtail connection he taken direct from the rod to the filament lead from the grid coil. "Bv doing this the losses from metal | end plates and bad connections hetween plates will he eliminated. while there. can he no losses in a reaction condenser if one is not used, This only leaves: the grid condenser and leak to he dealt with, and the trial of several of each will soon show which is the best. The coils will be found to give the greatest signal streneth when about two and a. half inches in diamcter,