Tom,
I'll give you an A in Sociology, but a D in math.
I think it's wrong to only add to 1 end and not the other. The correct
ratio is roughly 2 feet on the long end and 1 foot on the short end.
Per the formula on the link you provided last week:
For 132 ft. total length, long side = 132 X .64 = 84.48 ft.
short end = 132 x .36 = 47.52 ft.
This thing should tune on 80, 40, 20, 17, 12, 10. Also 6 meters if your
balun will handle it.
Good luck, see you this weekend, Steve KW3A
----- Original Message -----
From: "T Behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, October 09, 2008 7:35 PM
Subject: Windom analysis and troubleshooting
> Hi, folks.
>
> As promised, I had some time this evening to use my new TW1 to take some
> systematic SWR readings on my re-constructed Windom antenna.
>
> To give you the short story, my original windom was a coax-fed 80-meter
> Windom. It was fed by RG8U coax, and had a 4-1 balun at the feed point on
> my tower. The feedpoint and legs were all about 35 feet off the ground.
> The short leg was 44 feet long, and the longer leg was 80 feet long--which
> turned out to be way too short.
>
> Last Sunday, I had a friend come over, and we added 9 more feet to the
> long
> leg, based on re-calculating our formula for an off-center fed 80-meter
> windom. Our new calculations suggested that the proper length for the
> entire antenna should be 132 feet--44 feet on the short end, and 88 feet
> on
> the long end. The antenna heights are the same as before, and the new
> 8-foot extension on the longer leg is hanging down vertically, since I had
> no room to extend it horizontally.
>
> My SWR's are considerably better than they were before, but they still
> don't
> seem great. Let me give you some readings to show you what I mean:
>
> I took readings at the low end, the center, and the high end, of the
> following bands, and came up with the following SWR readings:
>
> 80 meters:
> 2.9 2.1 1.1
>
> 40 meters:
> 3.3 3.1 2.3
>
> 20 meters:
> 3.0 2.4 1.7
>
> 15 meters:
> 3.8 3.9 4.8
>
> 10 meters from 28.05 to 28.5(very surprising):
> 5.1 4.7 3.4
>
> 17 meters:
> 1.7 1.8 2.0
>
> 30 meters:
> around 8.1 to 1 throughout--basically untunable.
>
>
> I guess what surprised me the most was that the antenna was lengthened an
> entire 8 feet on the long end, and still seems to resonate toward the top
> of
> 75 meters, and I thought My SWR's would be better all around on 40, 20,
> 15,
> and 10 meters.
>
> The great SWR's on 17 meters also surprised me.
>
> I didn't expect the antenna to tune well on 30 meters, which is no problem
> since I never use that band anyway.
>
> Can anyone tell me what might be going on here? Does anyone have
> suggestions for modifications that might improve things?
>
>
> I think the antenna is clearly usable for this week-end's PA qso party,
> since the TS480 auto-tuner should tune it with no problem on 40 and 80,
> but
> I'm interested in trying to make things better all around.
>
> Thanks for any help you can give.
>
> 73 from Tom Behler: KB8TYJ
>
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