Steve:
I did some calculations last night, and alas, I think you're right on
target.
Now, here's a question. ... It may seem like a dum question, but I really
need a good answer here.
If I have to lengthen the antenna as you suggest, how do I make a splice on
each of the legs that will be electrically strong, and that won't break in
the wind, etc.?
I am now kicking myself that we didn't start with longer sections that could
later be pruned, but that's behind me now. ... Live and learn, I guess.
Would such splicing involve soldering, or is there another way I could do
it?
I am using 14-gauge insulated wire for the antenna itself.
Thanks for any help you or anyone else can provide on the splicing issue.
73 from Tom Behler: KB8TYJ
----- Original Message -----
From: "Steve Forst" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, September 29, 2008 1:53 PM
Subject: Re: windom question
> Tom,
>
> I went to the link you provided, and I've read that one before, since I
> have
> one of his antennas.
>
> Based on that formula and the demensions you have (80 ft. long side, and
> 45
> ft. short side) it seems it was cut for 3.75 mhz. That would be fine for
> a
> single band antenna, but you want it to work harmonicly on other bands.
>
> If it really is resonant at 3.750 mhz, then your first harmonic is 7.5mhz,
> then 15 mhz, and 30 mhz. Out of band, but workable with the tuner.
>
> Lengthen the antenna 7 ft. to get the resonant point down to 3.550 and
> now
> your harmonics are 7.1, 14.2, and 28.4 mhz. Just like God and Mr. Windom
> planned.
>
>
> There are always variables and you may never get all bands perfect and
> you
> may need to add mor or less than 7 ft. , but I thinkyou can get 20 and 40
> better, although you may see higher swr at the top end of 75. If you
> decide to add more wire, remember to follow the formula and for a 7 ft.
> addition add 4 and a half ft. on the long side and 2 and a half on the
> short
> side.
>
> I think this is why most commercial OCF antennas are cut longer. Easier
> to prune it and bring up the freq. than to add wire.
>
>
> Of course I may be full of crap, but it won't be the first time.
>
> 73, Steve KW3A
>
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