Tesla Coils - Resonance and Tuning

W. MORRIS JONES. — It is generally assumed that a Tesla coil gives the best effect (i.e., the highest secondary potential for a given primary discharge potential) when the two circuits are so adjusted that, separated, their periods of oscillations are equal. This condition is expressed by the relation L₁C₁= L₂C₂ and is commonly called the condition for "resonance" or "synchronism." In a recent paper Taylor Jones has shown that the above condition does not apply if the adjustment is made by varying the primary capacity alone, but that in this case the "optimum" value of C, is considerably greater than the resonance value. The author gives the results of an experimental investigation in which the chief conclusions of the theory were confirmed. — Philos. Magazine, January, 1916.