Re: Capacitor Help

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "James Zimmerschied" <zimtesla@xxxxxxx>

Malcolm,
I ran a similar size coil for a youth activity at a school. I hooked 
the secondary ground to a steam radiator for ground. Maybe the 
building where you will run this coil has some copper plumbing nearby?
On the safety gap - most people have a ground point in the middle of 
the safety gap so if a transient kicks back into the NST the high 
voltage will harmlessly jump to the ground point. You can easily make 
this from three pieces of #12 gage wire with a tight loop on one end 
of each wire.  A wire is connected to each high voltage terminal of 
the NST and brought out to about 1" apart. The third wire is 
connected to the NST ground and brought out to the middle of the gap 
formed by the other two wires. This will give about 1/2" clearance to 
ground on each side of the safety gap. With no other connections made 
on the high voltage size, you apply power to the NST to see if the 
gap fires. Then (with power off) adjust the gap until each side fires 
to ground with the NST on. Then (again power off) open the gaps a 
little. With the NST on there should be no arcing. Your main gap will 
be set closer (say 1/4" or less total gap) so it will fire before the 
safety will (which is good). If a kick back occurs (most often when 
playing with a rotary gap but from other causes too) the transient 
will pop across the safety gap and you will still have a working NST.
You can also add other filtering elements like caps, resistors or 
inductors to strain out transients, but the safety gap is the 
cheapest insurance for NST life.
Jim Zimmerschied
----- Original Message -----
From: <mailto:tesla@xxxxxxxxxx>Tesla list
To: <mailto:tesla@xxxxxxxxxx>tesla@xxxxxxxxxx
Sent: Friday, December 16, 2005 6:28 PM
Subject: Re: Capacitor Help

Original poster: "MalcolmTesla" 
<<mailto:tesla@xxxxxxxxxxxxx>tesla@xxxxxxxxxxxxx>
----- Original Message -----
From: "Tesla list" <<mailto:tesla@xxxxxxxxxx>tesla@xxxxxxxxxx>
To: <<mailto:tesla@xxxxxxxxxx>tesla@xxxxxxxxxx>
Sent: Friday, December 16, 2005 6:22 PM


 snip>
Owww this throws another wrench in the works.  A copper pipe hammered into
the ground hey...  hummm is this the only way?  I mean that's fine for
playing at home but the whole reason I started building the Tesla Coil is
because we are having a christmas tree decoration contest at work.  My team
as built a christmas tree cage from chicken wire and I'm building the Tesla
Coil (on my own dime) to go inside the tree cage.  We're not going to have a
copper pipe in the ground available there.  Is there an alternative we can
do?

snip>
I still don't understand.  How does the safety gap in parallel with the
regular spark gap help any unless it's connected to something else as well?