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N8WCT
12-10-2009, 11:26 PM
Im making plans on putting up a 10-80m Windom dipole as an inverted V...the feed point being 40' up, and both ends at about 12'. I know that HF SSB dipole is horizontally polarized (normally), and the null ends run out from each end. Ill be primarily working 20 and 40m digital modes, and voice on 75m.

My question is, what orientation should I install the antenna in Ohio?

Some say, a properly tuned Windom dipole will radiate in an omni-directional pattern. Others say to mount its length from north to south, as it will be directional perpendicular, IE, pattern going mostly east and west, and that is where most of the station work will be. Another few say to mount it east to west...directional north and south, and something to do with the rotation of the earth.

Any comments/experience/suggestions?

Thanks much, and 73!

-Chris

WB2WIK
12-10-2009, 11:29 PM
It won't matter much.

I'd install it in any direction that gives me the highest possible center elevation above ground, the highest possible end point elevations above ground, the the most possible clearance away from the house, neighbors' houses, utility wiring, and trees. (IOW, wherever the entire antenna will be highest, and most "in the clear" of everything.)

However that orients it will be the way it works best.

N8WCT
12-10-2009, 11:43 PM
The feed point will be a 40' utility pole which I will be installing. The space allows me to orientate in any direction. My lot is flat, and clear of any obsticals in every direction.

73,

-Chris

N0SYA
12-10-2009, 11:47 PM
Hi

This depends upon the band and the height of the antenna more than anything else. If you could mount a real 80m dipole (not a inverted v) at 60ft then you may notice directional effects. If you could mount a 10m dipole at 60ft you would definitely notice directional abilities. But as it is, being relatively low to the ground, orientation is moot, just install it as you find reasonable and don't worry about it.

WB2WIK
12-10-2009, 11:51 PM
Hi

This depends upon the band and the height of the antenna more than anything else. If you could mount a real 80m dipole (not a inverted v) at 60ft then you may notice directional effects. If you could mount a 10m dipole at 60ft you would definitely notice directional abilities. But as it is, being relatively low to the ground, orientation is moot, just install it as you find reasonable and don't worry about it.

That's pretty true. Fact is, a "Windom Dipole" (misnomer for what's usually a 33% off-center fed doublet) is very unbalanced and usually fed with a voltage balun (6:1 to 9:1) that allows the transmission line to radiate quite a lot, so the pattern, especially installed as an inverted vee with one leg twice as long as the other one, is very screwy and varies a lot from band to band.

I'd just put it up as high and clear as possible and use it, see how it works; if you're dissatisfied with its "directionality" (whatever that may be), you can always untie the two ends and move them somewhere else, leaving the center right where it was.

K0RGR
12-11-2009, 12:02 AM
I'll put in my usual plug for the KH2D windom variant. It really does work. http://kh2d.net/windom.cfm

If you can find the space to put up this 'double windom' I think you'll find it worth the effort. I had mine up between two very tall trees with the center at 40 feet, and for working the USA, it was great.

As for directionality, the main element of my windoms actually ran from northwest to southeast, which was probably about 90 degrees from what you'd really want it to be in this part of the country, but it didn't seem to matter at all.

K8JD
12-11-2009, 02:03 AM
I have had 80 and 40M dipoles and worked as much off the ends as broadside. Used a 40M dipole on 15M and had more signal off the ends .

W5DXP
12-11-2009, 12:49 PM
An 80m OCF (mistaken for a Windom) is a broad-side antenna on 80m and an end-fire off the long end on 40m. So there is no easy answer to your question. The free demo version of EZNEC available at www.eznec.com will model this antenna and give you the information you desire.

KC8WBK
12-11-2009, 09:58 PM
I am running a 40m-10m Carolina Windom oriented north/south with a qth in Michigan. It does a good job to the south.

G0GQK
12-11-2009, 10:42 PM
It all depends on where the propagation takes your signals, and there ain't much propagation these days. Living a long way from Ohio, I would think you would like to have chats with people to the east, south, and west, of Ohio, but as its in the inverted V shape most othe energy will go up and come down.... anywhere !

G0GQK

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