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Re: T-minus 7 days and counting...



>   
> 1    Does anyone have a formula for calculating the capacitance of a
> saltwater cap based on physical properties?
>   

Yes. You'll find it at:
http://www.velocity-dot-net/~djb/tesla/texts/math.txt



 4    These rubber expansion plugs use a large rubber grommet that is
> squeezed between two steel washers.  The washer on the top (outside) of the
> bottle is actuall touching the glass (nothing else except for the rubber).
> Does this pose a problem?  I really can't see how it's just that the plans
> I saw called for a plastic lid to be screwed on the bottle and I couldn't
> find a cap that would fit this bottle.


Kent,
I made mine with mason type jars ans metal lids. They performed great.
You shouldn't have any problem with the washers.


> 5    The plans called for wrapping the exposed foil on the outside of the
> cap with at least two layers of electrical tape.  Why is this when if it
> would get next to another bottle this would just be the ground anyway?
> Wouldn't it be better if all the bottles touched anyway?


Good question. I wrapped mine, but when they finally blew, it blew
through a piece of unwrapped, exposed glass. Might not have happened if
they'd been wrapped all the way up? Also, make sure you use a piece of
glass or plastic under the sheet of foil on the bottom of the box for
insulation from ground. It also wouldn't hurt to set the box up on a
platic bucket or insulator.

Don't know if size of terminals really matters. Mine were wide mouthed
jars, so I used 1/2" bolts. I seen some with wire thin terminals. As far
as capacitance, if you play around with the salt content and a meter,
you can watch what happens to your capacitance. I thought the less salt,
the higher the capacitance value - wrong. When I blew my smaller ones, I
kept adding salt in a quick one gallon cap until I had the necessary 3
nF.

Hope this helps.
Bob Volk