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Re: 3/4 wavelength secondaries



Tesla List wrote:
> 
> > > Subject: Re: 3/4 wavelength secondaries
> > > >Subject: Re: 3/4 wavelength secondaries
> > Subject: Re: 3/4 wavelength secondaries
> > > Subject: Re: 3/4 wavelength secondaries
> > > >Subject: Re: 3/4 wavelength secondaries
> 
> >From sgreiner-at-wwnet-dot-comMon Jul 29 21:40:06 1996
> Date: Sun, 28 Jul 1996 13:39:47 -0700
> From: Skip Greiner <sgreiner-at-wwnet-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: 3/4 wavelength secondaries
> 
> Tesla List wrote:
> >
> > > Subject: Re: 3/4 wavelength secondaries
> > > >Subject: Re: 3/4 wavelength secondaries
> >
> > >From hullr-at-whitlock-dot-comWed Jul 24 21:43:48 1996
> > Date: Wed, 24 Jul 1996 09:53:12 -0700
> > From: Richard Hull <hullr-at-whitlock-dot-com>
> > To: tesla-at-pupman-dot-com
> > Subject: Re: 3/4 wavelength secondaries
> >
> > Tesla List wrote:
> > >
> > > >From rwstephens-at-ptbo.igs-dot-netTue Jul 23 21:47:18 1996
> > > Date: Tue, 23 Jul 1996 15:23:28 -0500
> > > From: "Robert W. Stephens" <rwstephens-at-ptbo.igs-dot-net>
> > > To: tesla-at-pupman-dot-com
> > > Subject: Re: 3/4 wavelength secondaries
> > >
> > > >>From MALCOLM-at-directorate.wnp.ac.nzSun Jul 21 22:11:11 1996
> > > >Date: Mon, 22 Jul 1996 08:34:11 +1200
> > > >From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
> > > >To: tesla-at-pupman-dot-com
> > > >Subject: Re: 3/4 wavelength secondaries
> 
> 
> > Malcolm, all,
> >
> > I must note that there is probably a lot of semantics here.
> >
> > If one is talking about the classic formula for a quarter wave wire
> > length based on frequency and the speed of light, then it will forever be
> > physically impossible to wind that length of wire into a coil and
> > resonate at the specified resonant frequency!
> >
> > It is possible to wind a coil which, without any terminal whatsoever, can
> > have a quarter wave resonant frequency of virtually any frequency
> > desired!
> 
> Richard: That is the $64 question. Can you give me the dimensions or the means of
> determining the dimensions for a 1/4 wave coil...any frequency would be fine but
> hopefully between 100 and 200khz.
> >
> > Finally, any terminal load, even the bolt, will lower the output
> > frequency of any coil!  The 100KHZ example given by Robert would be
> > affected so little as to not be worth discussing.
> >
> > Richard Hull, TCBOR
> 
> Yes, agreed, anything around will lower the frequency of the coil, but we can always
> take off a few turns to get the coil close again. Malcolm and I have discussed this and
> we both do not believe it is possible. Robert W. Stephens put up an excellent post on
> this subject and indicated a coil which he wound which resonated within 3% of its
> length. I will be trying to duplicate his effort and will post my results.
> 
> Skip

Skip, Robert, All,

I would be utterly amazed if anyone could ever wind a tight wound coil of 
wire length "x" based on a specific quarter wave length determined by the 
classic wire length VS speed of light/frequency equation and had it 
resonate within 3% of this value!!!!!!!  It just can't be done! At least, 
at our operating frequencies (50khz-2mhz).  It might be done on a form of 
1/4" diameter rod of about 50% of the full 1/4 wavelength long though.  
Not sarcasim, but probably a fact!  I cannot give any equations or 
dimensions for precise winding data.  I just know it can't be done on a 
form you could handle or build indoors.

Richard Hull, TCBOR