Here is a commercial implementation of MF / HF transmission lines.
(They are not telephone lines.)

http://members-central.optushome.com...3ase/feed2.jpg

http://members-central.optushome.com.au/vk3ase/feed.jpg

Owen

On Mon, 1 Aug 2005 17:43:34 -0700, "greg knapp 5"
wrote:

I need your advice, as I have never worked with open wire lines before.
I need to feed many different antennas with open wire line and need to run
the feeline from each about 200 feet from the back pasture to the shack. I
don't want to walk out 200 feet and throw knife switches to chose the
antenna/feedline I want to feed, so I plan to run separate 600 ohm open
feeds for each antenna all the way to the shack.
The problem is I don't know what the effect is or how to handle the
multiple open wire feed lines, as they will be parallel for probably 150-200
feet. I haven't found anything in literature describing this.
For instance, will they interact? how far do you space the feedlines from
one another? If I have 4 feedlines, can I stack them vertically or
horizontally one foot apart from each other? How much is enough separation?
What other precautions do I need? Need they be twisted if they are not near
anything other than the other feed lines?
Any help is appreciated.
73,
Greg, N6GK

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