Re: Beginners, lost?

To: tesla-at-pupman-dot-com
Subject: Re: Beginners, lost?
From: Rodney Davies <rodney-at-johnxt7.anu.edu.au>
Date: Tue, 11 Jun 1996 13:06:58 +1000 (EST)
Hello Zoda,

On Mon, 10 Jun 1996, Tesla List wrote:

> I am winding my first coil as per the TESLABLD.ZIP file off of KEELYNET.
> Is there something that goes on top of the coil to send 
> out sparks?    The last messages to TCBOR TC VIDEO PRIMER lead me to think
> so.
> Can anyone help me


Yes, you require a top metal electrode of some kind. I toriod would be 
ideal.
Just a few things to remember -
Keep the diameter of the top electrode at least 2 or 3 inches 
(preferably more) greater in diameter than the diameter of your 
secondary coil.

If you're using a flat pancake primary coil, it might be an idea to make 
the diameter of the electrode (I am assuming a toroid), just a little 
larger than the diameter of the primary coil. This helps for field 
stresses and helps to promote the arcs to stream outward in a horizontal 
fashion.

Try to keep the electrode raised perhaps 4-10 inches above the top of 
the coil - vary this height with experiments, there probably isn't a set 
specific height, and you will only get the best position by trying 
different heights and experimenting.

 From this you will notice that the arcs will start streaming downwards 
(when electrode is very close to the secondary top), then as you raise 
the electrode more, you will notice the streamers will start moving out 
horizontally, then more to an upward direction.
Be carefull not to go too high as the last few windings of the 
secondary will start to break down - This is not good when that happens.

Preferably, keep the metal surface area of the electrode as smooth as 
possible. Little bits sticking out will cause damage and the arcs will 
only come from the sharp edges.

Also, when building a support for the top electrode, don't use metal, 
use some sort of good insulating material, ie PVC pipe.
 
Make sure that nothing pertrudes inside beneath the top of the 
secondary, as you may experience internal arcing - this causes servere 
damage. 


That's about all I can think of, the others in the group may correct me 
on a few errors (if any) and perhaps suggest even better ideas!

Happy constructing!

Rod

-- "Who are the Federal Communications Commission and why do they 
    want my Tesla Coil?"

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| Rodney Davies                                                             |
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