Re: Difference between 1/2 wave and 1/4 wave resonance ? ? ?

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

Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>

Hi Dan,

The 1/4, and 1/2 wave "stuff" as it applies to Tesla coils is all screwed 
up...  Mostly myth from old times.

People used to make the secondary wire 1/4 wavelength long because they 
thought the Tesla coil was acting like a whip antenna were antenna length 
is so important.  They failed to realize that the turns on the coil were 
all magnetically coupled.  Tesla coils work just fine regardless of if the 
wire length is close to the 1/4 wavelength or not.

A RLC circuit has an Fo frequency and you can certainly find the wavelength 
given that frequency:

L = 186282.397 * 5280 / (4 x Fo)

But the wavelength has practically nothing to do with the RLC components 
themselves.  If the L is 50mH, any 50mH coil gives the save results...

You may want to check out Paul's papers on this:

http://www.abelian.demon.co.uk/tssp/

http://hot-streamer-dot-com/temp/pn2511.pdf

http://hot-streamer-dot-com/temp/pn1401.pdf

Hope this helps.

Cheers,

         Terry





At 01:54 PM 1/12/2004, you wrote:

>Does anyone have how to calculate from an RLC circuit, both the 1/2 wave
>and 1/4 wave resonant frequency?
>
>A simple parallel resonant circuit Fres = 1/SQRT (L*C).  Now is this
>technically a 1/2 wave resonant frequency of
>this parallel resonant circuit?
>
>Any help appreciated in this confusing matter.
>
>Thanks
>Dan