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Joey_migs
Junior Member
Username: Joey_migs

Post Number: 33
Registered: 9-2009
Posted on Monday, October 05, 2009 - 1:21 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I am working on a portable two element Yagi (11 meter) that can be easily implemented in the field. I can use a cross bow, bow, or wrist rocket sling shot and 40 lb test fishing line and a 4 oz. lead sinker to get it up and over a lofty tree limb. Then pull a more robust poly cord up and over the said limb and back down. Referring to the attached diagram:
1) What spacing between elements should I use? I have seen both 0.1 lambda as well as 0.25 lambda in various articles and ARRL books.
2) The feedpoint of a dipole is about 72 ohms, I am feeding directly with 50 ohm Rg-58 or Mini 8, does the parasitic director element affect the feed-point impedance on the driven element?

Thank, in advance,

Joe
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Tech237
Moderator
Username: Tech237

Post Number: 1235
Registered: 4-2004


Posted on Saturday, October 10, 2009 - 10:57 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Can I email you the diagram for an antenna that might fill your needs and work a little better?? Currently it is dimensioned for another band, but I'll include the sizes for 11m.
Simon
Tech237
N7AUS
.
I thought he said, "there was no rust for the wicked, and I own an MGB"

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