View Single Post
  #6   Report Post  
Old April 28th 06, 05:01 PM posted to rec.radio.amateur.antenna
Tom Donaly
 
Posts: n/a
Default Missing Degrees in Mobile Antennas?

wrote:
Poor Yuri.

Hanging his hat on Cecil, but now Cecil is getting the picture and
yanking the rug out from under Yuri and his "missing electrical degree
cutrrent taper and phase shift theory".

It only took three or four years, but at least that's better than
Fractenna. :-)

Cecil Moore wrote:

The whole point is that it doesn't differ.
That's how my bugcatcher works.

Here are the three parts to the answer.

1. The base-loading coil furnishes a delay equal to
a certain number of degrees which is nowhere near zero
degrees. Half of a coil self-resonant at 4 MHz would
provide 45 degrees of shift.

2. Using EZNEC to add a stinger to resonate the antenna
on 4 MHz, I find that's 11.5 degrees of straight element.
45 degrees plus 11.5 degrees is 56.5 degrees.

3. 90 - 56.5 = 33.5 degrees which is the "missing"
degrees filled in by the impedance discontinuity.
We can even estimate the ratio of the Z0 of the coil
to the Z0 of the stinger to be 5.0.
--
73, Cecil
http://www.qsl.net/w5dxp



Yes, except that Cecil is just replacing one idiotic theory
with another. That's o.k., he has to do something out there in
the Texas hinterlands to keep out of trouble. The unfortunate
thing, though, is that there might be someone in this world who
takes him seriously.
73,
Tom Donaly, KA6RUH