Cecil Moore wrote:
"Gene Fuller" wrote:


Do you really think the Vf is dependent only on the turn density and not
the number of turns? Corum never says such a thing, ...


Already asked and answered. He certainly does imply such a thing in Fig. 1.
The VF is dependent only on the turn density and the diameter of the coil.
The number of turns affects the length of the coil. The length of the coil
is NOT a parameter in the graphic nor does it appear in the equation.

Does a 1/4WL transmission line have a different VF when it is increased
to 1/2WL?


Where is the transition in Vf from the ~1 for zero
turns to ~0.02 for a resonant coil?


Already asked and answered. If you cannot read Fig 1, then you have
a problem. The VF in the graphic goes from 0.0 to 1.0.


Cecil,

You just contradicted yourself. Yes, indeed, Fig.1 shows Vf going from
0.0 to 1.0. But as you pointed out, there is no dependency on the number
of turns anywhere in the chart axes or in the plotted data. It would be
useful if you looked at the caption on that figure to attempt to
understand what is actually being plotted. The vertical scale is Vf and
the horizontal scale is D/lambda. The parameter attached to each curve
is "N", which is defined as the turns per wavelength.

We would expect a very short coil to look like a straight wire, with a
Vf near 1.0. How does the Vf transition to 0.02 for a resonant coil
occur? That transition is most certainly NOT shown in Fig. 1.

73,
Gene
W4SZ