Nikola Tesla Books
CHAPTER III. THE HIGH POTENTIAL TRANSFORMER OR INDUCTION COIL. As the reader will have inferred from the preceding chapter, the condenser discharge principle is employed in the construction of all of the apparatus described in this work. While the use to which each particular outfit is to be put governs, in a large measure, the actual construction and design of the component parts of the apparatus, the basic principle is quite the same in each case. Granting this, each outfit will comprise the following units: The Transformer or Induction Coil which converts the low voltage current available from the lighting circuit, or perhaps a battery, into a high voltage current suitable for charging The Condenser, which is composed of alternate sheets of metal and glass or other material having a high insulation resistance. The condenser discharges its load of electric current at high pressure across The Spark Gap, which is composed, essentially, of metallic electrodes, having accurately turned faces held in the same plane by means of suitable supports. In series with the spark gap and condenser is the primary of The Oscillation Transformer, which comprises two coils or helices of copper wire. One of these coils, the primary, is composed of a few turns of thick wire, while the secondary may have from ten to one hundred times as many turns of fine wire. 16
