Nikola Tesla Books
Other arrangements of apparatus with open secondary for exciting sensitive device.
In this plan (4.) the secondary S is connected to the terminals of sensitive device a through a small condenser CC1. A very small condenser is sufficient to cause the excitation.
This is a modified arrangement (5.) there being only one condenser and besides a very high self-induction around device a to provide for initial excitation when device a is originally of practically infinite resistance. The relay R may be placed around device a instead of self-induction l.
In the diagram below (6.) is shown a manner of connecting apparatus to a circuit L1C1 which is adjusted to be in synchronism with the primary vibrations of the oscillator and excites device a.
Again in Diagram 7. a special synchronised circuit is done away with, the secondary itself being adjusted to the primary vibrations. The plan adopted in New York apparatus
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