High Frequency Apparatus Page 59

Discharge ball INDUCTION COIL OUTFITS 59 Wind with about 600 turns of Ko. 28 to 34 D.C.C. in one layer with turns spaced. Oscillation transformer Condenser Groun Gap wwwww риги Induction coil Diagram of connections Primary 12 turns of heavy copper or brass. wire. For induction oo!! sets, primary to be 1 times diameter of secondary drum. Figs. 3 and 4. Data for small Oudin resonator and diagram connections the spark gap. When operating the coil, try various capacities of the condenser, a variation of the turns of the primary, closing up or opening the spark gap, etc. A few trials will bring the circuits into resonance and the ball at the top of the resonator will give out beautiful streamers of purplish fire. If a piece of metal is held in the hand and approached to the ball, a spark several inches long will jump into the metal without the operator feeling the slightest sensation of shock. Induction Coil Construction.-In the event that the experimenter is not the possessor of an induction coil giving a fat, hot spark, he will need either to buy one outright or else construct one in his home workshop. The latter course is permissible if he is a fairly careful and patient mechanic.