Useful Hints

Radio Record, Volume V, Issue 25, 31 December 1931, Page 27

Useful Hints

A THIN piece of metal-much too thin to be self-supporting-is quite satisfactory when secured to a background of stiff cardboard or three-ply work to act as a sereen, , AMON G the rough-and-ready emergency screens which can be used are cigarette packet foil, or a thin coat of aluminium paint or gold paint, QNE reason why it is dangerous to short an accumulator is that such a battery has a very low internal resistance, and, therefore, delivers an enormous current on short circuit, ® ror receiving short-wave Morse, as distinct from broadcasting, it is advisable to use a high-ratio audio transformer, owing te the greater sensitivity of this arrangement, "THE output filter on a short-wave set tends not only to eliminate handcapacity effects but also to decrease the liability to threshold howl.