On Mar 30, 4:39*pm, Cecil Moore wrote:
Cecil Moore wrote:
Seems to me the large air-core
coil occupies a greater number of degrees of antenna
than does the toroidal inductor.

I've received a number of emails requesting that I
explain what I meant by this statement. It is easiest
understood by people who can solve the following
problem.

How can the impedance looking into the following
physical 45 degree, dual-Z0 stub be purely resistive,
i.e. electrically 90 degrees and resonant?

---22.5 deg 300 ohm twinlead---+---22.5 deg 50 ohm coax---open
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com

Exactly as my tests have shown me. Using a coil and toroid with given
same inductance say 20uH to achieve the same resonance the top part of
the vertical over the toroid was about 8" longer, then the top
portion of the vertical over the coil, just as you stated, More
electrical degrees in the coil than the toroid.
I was wondering if the self shielding properties of the toroid would
have contributed to this conclusion, and because of these properties,
the toroid not have any electrical degrees, so to speak, so when it
come to the radiating element it would need to be slightly longer to
see the electrical degrees for the wavelength or resonance frequency
injected into it. thanks again for the info.