Re: Rotary Spark Gap Design

To: tesla-at-pupman-dot-com
Subject: Re: Rotary Spark Gap Design
From: Richard Hull <hullr-at-whitlock-dot-com>
Date: Mon, 20 May 1996 15:22:03 -0700
Tesla List wrote:
> 
> > Subject: Re: Rotary Spark Gap Design
> 
> >From sgreiner-at-wwnet-dot-comFri May 17 21:43:31 1996
> Date: Wed, 15 May 1996 00:09:22 -0700
> From: Skip Greiner <sgreiner-at-wwnet-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Rotary Spark Gap Design
> 
> Tesla List wrote:
> >
> > >From MALCOLM-at-directorate.wnp.ac.nzThu May 16 21:47:03 1996
> > Date: Thu, 16 May 1996 16:45:48 +1200
> > From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
> > To: tesla-at-pupman-dot-com
> > Subject: Re: Rotary Spark Gap Design
> >
> > Hi everyone,
> >              Greg, I'm glad I'm not the only one who thinks modelling
> > the coil isn't simple. Just a reply if I may on transmission lines...
> >
> > > 3. Resonance - Secondary coils are highly resonant, as everyone
> > > here has witnessed. Xmsn lines are, by definition, wide-band and
> > > therefore non-resonant.
> >
> > I think that is only true when the line is terminated in it's Zo at
> > each end making it a matched line. A piece of coax (for example) that
> > has any other termination or is shorted or o/c has a high VSWR and is
> > highly resonant (Y-N)? We had a problem here where a 50 ohm data link
> > cable had a piece of 75 ohm coax added in by mistake. Reflections and
> > high VSWR meant the link failed totally. I designed a 1.2:1 line
> > matching transformer to correct this problem, one inserted at each end
> > of the 75 ohm cable.
> >     I think your model of a sinusoidal voltage/current distribution is
> > actually quite accurate.
> >
> > Malcolm
> 
> Malcolm and Greg
> 
> Don't we really want a transmission line with a large vswr with the max
> point at the top of the coil?
> 
> Skip


Skip, 

You are dead on!!!  I have just written malcolm about this reverse radio 
logic!  Yes, we seek to avoid the nasty and disgusting radio buff unity 
VSWR on our antenna.  We must strive for an infinite VSWR, Always!!!  
Just think radio, backwards.  We wish to do the most ruinous thing to an 
RF radiative signal at all times.  All the power to total loss, in air, 
at the end of the antenna with not so much as a pico-watt of radiative 
energy leaving the vacinity. (ideal Tesla coil)

You old radio buffs are wakin' up and smellin' th' coffee.  Actually this 
is the sign of a maturing coiler who is starting to grasp what the coil 
is really supposed to be doin'!

Richard Hull, TCBOR