Wire length,resonance, and Q

To: "'Tesla List'" <tesla-at-pupman-dot-com>
Subject: Wire length,resonance, and Q
From: Tesla List <tesla-at-stic-dot-net>
Date: Tue, 12 May 1998 01:07:47 -0500
Approved: tesla-at-stic-dot-net

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From:  bmack [SMTP:bmack-at-frontiernet-dot-net]
Sent:  Monday, May 11, 1998 9:43 PM
To:  tesla list
Subject:  Wire length,resonance, and Q

To all,

When Dr. Tesla made initial coil designs, he often resorted to quarter
wave length calculations as a guide.  My early impressons of this was
that it was the upper boundry for the physical length of wire that could
be used.  Since, however I found that this is not neccessarily the case.

The most intriguing thing is the cases where the coil resonates at 
frequency HIGHER than the wire length alone indicates!  Malcolm made
a passing refence to this in one of his recent posts as well.  Preliminary
quick experiments indicate that the coil geometry has alot to do with it's
ultimate resonant frequency apart from the length of the wire.  Really 
bizzare things happen when the aspect ratio is below 0.1.

According to conventional physics, (let me know if I missed something)
a charge and it's attendant feilds will propagate faster  in a straight
wire
than in a coil. It follows that the coil should always resonate lower than
the wire since the velocity is less than the speed of light.

Why then, do long space wound coils resonate at a frequency higher
than expected? This has nothing to do with the LC ratio either. I would
expect that no matter what gain or reduction of L vs C for a given
geometry, they should always result in a frequecy lower than that of
a straight wire.  Whats going on here???

Before I go and re-invent the wheel, does anyone have an explaination
and/or experimental data on this?

Curious in NY
Jim McVey