Hi Richard,

You remind me that I do not understand something. Let's say the
characteristic impedance of this 540' loop is in the neighborhood of 140
ohms in free space, or even as you say closer to even 35 ohms in reality.
Your point was, if I understand correctly, that this is in the ballpark
of 50ohm coax and you suggest it can just as easily be fed into the coax.

But I thought that coax is unbalanced and the point was to go with a
balanced feed line?


I guess I am not understanding the relevant differences between balanced
vs. unbalanced feedlines, and getting the impedance of the the
transmission line close to the impedance of the antenna.

I thought the point of my striving to use balanced ladder line was to
somehow gain something that would be compromised by using coax. I thought
that the the ladder line which might be 488 ohms say is still going to be
a better feedline than using the 50ohm coax. The coax would still then
require a balun, correct? (a 1:1 banlun?).


It is sites like this: http://www.cebik.com/par.html that tend to get
one thinking about this whole diy approach.

My reading and gleaning of websites has me of the opinion (at this point)
that the balanced line with this long loop is better (multi band) than to
feed it with coax.

I believe Cecil has already explained this in terms of the wide range of
actual resistance that may be encountered multi band. (hey, I am just now
learning to talk this lingo....just barely know what I am talking
about....operating intuitively, and with the kindness of strangers.......



Zeno (aka Bill) KG6UHM for the moment.....



Richard Clark wrote:

On Tue, 20 Apr 2004 06:23:13 GMT, zeno wrote:

Any recommendations on a specific type of commercially made window
(ladder) line? I see that it comes in a variety of configurations
and slight differences in Z.

This feed line will be for a full wave 160m loop.

Hi Bill,

You repeatedly characterize this as 160M and given the size and height
- Why do you think you need ladder line when it will in all
probability fit quite nicely into a coax?

In free space, it may show as much as 140 Ohms R; however, within the
cold embrace of earth only 50 feet away, you will barely muster 35
Ohms at resonance.

73's
Richard Clark, KB7QHC