Re: Mini Tesla. Dangerous Stunts

Hello Gary, All 

Gary wrote:
 I don't use a secondary coil earth ground on this TC, the bottom end of the
secondary coil is connected to the  inside turn of the primary coil.  It
produces 3" long discharge sparks.  I can touch the sparks with my finger and
almost can't feel them and the sparks make a warm spot on my finger tip.  

I would be pretty careful about this. Connecting the bottom of the secondary
to the primary does result in longer sparks in comparison to having the
secondary not grounded at all, but:

1.) Doing so, you are superimposing 60 (!!) cycle high voltage upon your
secondary. This is not something you really want to be touching. These 60
cycles are what you are feeling. If it was true RF, your nerves would not
respond to it, but this doesnīt mean it wouldnīt cause any internal damage. I
believe it was Bert Hickman that once posted a comment on "skin" skin depth
and found the skin depth in flesh to be much deeper than anyone has
anticepated (sp?) so far. The "skin depth" was much deeper than your hand is
thick !!

2.) Your lower end connection does not provide a true ground, so your coil
will resonate at a somewhat different frequency than you might be thinking.

3.) Allowing an RF current to flow back into your xformer, etc. is not a good
idea. With this small setup you should be lucky enough that the HV xformer
dampens out the RF enough, so that you wonīt be superimposing a lot of RF
spikes on your mains, but I would never do this in a higher powered setup.

4.) True (pure) RF can cause flesh burns. So if you really insist upon doing
something like this, I would "get" the spark by holding something metallic in
your hand (pliers, copper rod, etc). That way, you wonīt be taking a point to
point hit.

Probably most of us coilers (including me) have done something like this, but
after reading some posts which include the newer understanding of RF currents
involed in coil work, I would not recommend doing this any more. The reason (I
believe) why most of us havenīt gotten hurt by doing these stunts is simply
because of the fact that the coils these stunts were tried on, didnīt have
lots of power (meaning the internal damage was minimal).

Letīs try to keep the statistical deaths down to that one poor soul who got
zapped while doing a similar stunt.

BTW: Tube coils are even more dangerous because they are of CW discharge type.

Coiler greets from germany,