Re: tesla design details

 * Original msg to: Des-at-ellijay-dot-com
 * Carbons sent to: usa-tesla-at-usa-dot-net

Quoting Doug Swanson <des-at-ellijay-dot-com>:

> I understand that when I've gotten the primary set up, with the
> 12 - 15 coils, it should be tuned.  

This would be ideal, most likely this will not be a tune point
until later when the system is beaing "peaked".

> As I perceive it, the most inner point of the spiral is usually
> the "common", and the the tuned placement of the other 
> conductor is placed near, but not necessarily at the outer
> perimeter of the primary.  how do I determine this? or is it 
> trial & error, with more obvious results being made as I reach
> the proper position in relation to the harmonic resonance to 
> the secondary?  

First off, the inner turn of the primary is not necessarily
"common" or ground. Many people (myself included) let their
primary coils "float" hot. There is no "common" in many of the
best Tesla tank circuits. Tuning without the aid of expensive
diagnostic equipment is a learned "art". You start with some
rough math calculations based on the known tank circuit
parameters. One of the many Tesla coil calculator programs can
shave a few hours (and errors) off of this pencil work. Using
your rough math, you place your movable "tap" lead to the turn on
the primary where you calculate/guestimate your tune is going to
be. First you fire at low power. Using several indicators:
glowing from low pressure gas tubes, safety gap activity, and
main spark gap sound, you establish a rough low power tune. Then
you increase power in steps, stopping to make frequent
adjustments and observations. When spark begins to break out from
the discharge terminal you can better visulize the tune and
better qualify your adjustments.

Richard Quick

... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12