Roy

Tnx for the reply. Is the 1/4 or 1/2 wl feed line you desribe measured using
the fundamental (1wl) freq. of the loop or the operating freq.?

Terry
W8EJO


"Roy Lewallen" wrote in message
...
I've successfully used two feedlines for a single antenna (my "Field Day
Special", for reversing the direction) by making the feedlines an
electrical wavelength long and leaving the unused one open. In my case,
I wanted an open at the unused feedpoint, rather than a short as you do.
Also, you don't need that much length. Either of these should work for
your antenna, producing a short circuit at the connection point of the
unused feedline:

1. Make the feedlines an electrical quarter wavelength long and leave
the unused one open circuited.
2. Make the feedlines an electrical half wavelength long and short
circuit the unused one.

Whichever one you choose, don't "ground" the unused feedline or connect
it to anything else.

Anyone else trying this method should be aware that even a small amount
of feedline loss translates into a poor open or short at the antenna, so
loss usually has to be considered. In this particular case it won't be a
problem.

Roy Lewallen, W7EL

T.E.O wrote:

. . .
My problem is that I'm not sure of the effect of adding that second
feed line. Should the unused feed line be grounded or simply left
unconnected at the transmitter? Or should I use relays at the
feedpoints to "jumper" the unused feedline? I use 450 ohm "window" type
ladder line.

. . .