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Old February 8th 04, 05:27 AM
Doug Smith W9WI
 
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Hammer wrote:
Hi,
Putting up a 10 through 160 or 10 through 80 meters dipole. I have lots of
wire and coax and a 1:1 balon. Interested in how the shape or form of this
dipole should be to work properly? I have to put it into two trees to get
height. Are there any good links or sights to learn proper making and
installation?


A lot depends on how much space you have.

A straight dipole with a 1:1 balun and coax will only cover one band.
Well, maybe two if you cut it for 40 meters. (it'll then work OK on 15
as well)

You have a few other options:

- Make the dipole as long as possible (the exact length is unimportant);
don't use the balun; use ladder line instead of coax; and connect it to
a tuner in the shack.

- Run several dipoles in parallel. 132' for 80m, 66' for 40m, 33' for
20m, etc. They can all share the same balun and coax.

- Trade the 1:1 balun for a 4:1 and put up an off-center-fed dipole. A
132' antenna, with 44' on one side and 88' on the other, will work well
on every band between 80 and 10 with the exception of 15. (and it's
close enough on 15 that if your rig has an autotuner, it'll work there
too)

I've got the latter antenna. It's the most "bang for the buck" in my
antenna collection. (it even works halfway decent for DXing the AM
broadcast band!)

A good general rule for wire antennas is as high as possible, as
straight as possible, and as far from obstructions as possible. And
don't sweat it if "as far as possible" isn't very far. (UNLESS the
obstruction is a power line!)
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com