# Re: Sparking behavior and a magnifier question

• To: tesla
• Subject: Re: Sparking behavior and a magnifier question
• From: chip (Chip Atkinson)
• Date: Mon, 11 Dec 1995 16:27:56 +0700

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>>>
If the primary and extra coil oscillate at f, then the secondary should
be quarter wave reseonant at a substantially higher frequency near BUT
NOT EXACTLY EQUAL to 2f.  You do not want resonance effects from the
secondary, only transformer action.

<<<
Hmmmm... Now I'm a little confused.  Is the extra coil the base fed
coil that is producing the sparks?  That means to me that we have a situation
like this:

f================>2f===============>f
Tank circuit      driver coil        Final, sparking, extra(?) coil.
coupled to
tank circuit

.
. (Previous stuff deleted)
.
>>>>
The above will absolutely work.  The problem is the impedance of the
primary circuit with component values we are used to is too low and
would provide a bad match to the secondary.
<<<<

Ahhh.... That brings me to the one question that has bugged me for years:
What is impedance matching?  I kind of know the term, in that you need
the same impedance (ohms?) at a given frequency for maximum power transfer
in an AC circuit, but why?  Is it possible to explain in "layman's terms"?

Here's another question that occurs to me:  If I could create a tank circuit
that had standing waves in it, I should be able to connect the base of
an extra coil to an anti-node on the wave and, assuming that the extra coil
is tuned to the same frequency as the standing waves, get resonance/sparks
from the extra coil.  The question really is, does the primary/secondary
of a magnifier setup provide a fixed anti-node (maximum oscillation) to
attach the base of the extra coil?  (All this totally ignores impedance
matching, as I know little about it :-))

Chip

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