Re: Tesla Coil Blunders

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "John H. Couture by way of Terry Fritz <twftesla-at-uswest-dot-net>" <couturejh-at-worldnet.att-dot-net>


Tesla Coilers may be making the worst of TC blunders when doing calculations
for determining the operating resonant frequency of their coils. It is a
well known fact that the calculated frequencies do not agree with the actual
operating test frequencies. Many important design decisions are based on
this unique frequency so it is important that it be correct. To circumvent
this problem a fudge factor is used for all TC computer programs but this is
only a bandaid for TC design.

The equation that coilers use for finding the TC resonant frequency is

      F = 1/(6.283 x sqrt(LC)

The TC secondary circuit is an RCL circuit but the "R" is omitted by coilers
in the above equation which may be the worst of TC blunders. In the Tesla
Coil Construction Guide page 5-1 the complete resonant frequency equation is
shown including the "R" parameter. It is also mentioned that the "R" reduces
the resonant frequency and if the "R" is large enough there will be no
resonant frequency. In other words the "R" could be the reason the operating
frequency does not agree with the calculated frequency when the "R" is
omitted.

To my knowledge no one has ever determined how to find this very important
"R" for an operating Tesla coil either by calculation or by tests. TC
programs are hurting because of this lack of information.If anyone has any
comments I would be interested in them.

John Couture

--------------------------------