On Jun 14, 12:25*am, K7ITM wrote:
Cecil Moore wrote:
On Jun 13, 1:55*pm, K7ITM wrote:
*It doesn't make any sense to me to put a shorted
section of line in series with another line, so my confusion starts.

Tom, I didn't know initially that the example was in "Reflections
III". A series stub can be used instead of a loading coil on a wire
antenna. I had never seen a series stub used in such a manner on a
transmission line and that's why I was confused. I'm assuming that the
center conductor is broken and one side is connected to the inner
conductor and one side is connected to the braid on a stub, but I am
not sure that is correct. There's got to be a less complicated example
that we can use.
--
73, Cecil, w5dxp.com

Ah, OK. *Now I understand what Walt meant... *Though it's possible to
use a series stub on a transmission line, as you say, it's not all
that common in practice. *I suppose that's why my mind wasn't going
there. *Mea culpa. *Perhaps now I can go back and look at Walt's
original question and make more sense out of it.

When a series stub is used in an antenna (as in a quarter-wave stub
coupling colinear half-waves), King points out that coupling from the
antenna fields to the wires in the stub, when the stub is an open-wire
line perpendicular to the axis of the half-waves, is an important
factor in how the stub operates to establish in-phase currents on the
adjacent half-waves... *I see you made a comment about antenna
currents on the stub in John Smith's example, too.

Cheers,
Tom


Tom and Cecil,

My use of the series stub wasn't meant to be of practical use. I used
it only as a tool to explain a simple matching procedure. I used
series rather than parallel, because I wanted it to be simple to use
for those who are not as accustomed to admittance procedure as they
are with impedance. Sorry if I misled you.

Walt