Re: K formula?

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

Original poster: "Bert Hickman by way of Terry Fritz <teslalist-at-qwest-dot-net>" <bert.hickman-at-aquila-dot-net>

Hi Peter,

If:
  F1 = Upper Resonant Frequency
  F2 = Lower resonant Frequency

then the coupling coefficient is:

  k = ((F1/F2)^2-1)/((F1/F2)^2 +1)

So, for your system:

  k(0.0") = 0.1104
  k(0.5") = 0.0981
  k(1.0") = 0.0876
  k(1.5") = 0.0769

It appears that you may have a fairly large gap between your innermost 
primary turn and the secondary winding.

Best regards.

-- Bert --
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Tesla list wrote:

>Original poster: "Peter Lawrence by way of Terry Fritz 
><teslalist-at-qwest-dot-net>" <Peter.Lawrence-at-Sun.COM>
>
>Is there a formula for the K (coupling coeff) given that I know the two
>resonant frequences that the combined primary plus secondary have.
>Here are some example data I collected last weekend,
>204.8 KHz primary and secondary resonant frequency, when measured appart.
>Then when together at various secondary heights I get:
>at 0"     193.42  and  216.10  KHz resonances,  22.8 Hz appart
>
>at .5"     194.72  and  214.86  KHz resonances,  20.1 Hz appart
>at 1"     195.83  and  213.81  KHz resonances,  18 Hz appart
>at 1.5" 196.92  and  212.70  KHz resonances,  15.8 Hz appart
>
>thanks,
>-Pete Lawrence.
>
>.