Show Extension Handle Will Aid Radio Set Builder Occasionally It Is desired to have some other form of controlling device for variable 'elements in a radio set or Wter other than a dial. A very simple one may be made by obtaining a knob of composition that has a shnft hole to lit the instruments to lie used. Then drill 11 one-eighth-inch hole ' In the knob to take an extension handle made from a six-Inch length of wood dowel pin. A little shellac . will hold the pin In the hole drilled. Then pro cure a protractor from the nearest stationery store and fasten It to the panel above the Instrument shaft and knob and pointer. The pointer may be bougbt with the knob or made from strip brass. . |