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Ralph Mowery · July 25th 16, 09:55 PM posted to rec.radio.amateur.antenna

In article ,
says...

In article t,
Ralph Mowery wrote:

Yes, I want a 6:1 balun. It is for an off center fed antenna that is up
around 50 to 60 feet. To be used from 80 to 10 meters. I have had one
up for a number of years and used a 4:1 bought balun that is suspose to
be good for 5 KW. It heats up and the SWR goes up after several minutes
of SSB usage with about 1200 watts. Works fine at 600 watts. My
research seems to incicate that at that height a 6:1 is a beter match.

Since the feedpoint impedance of an OCF is a function of the feedpoint
location (how far off-center it is), could you reduce the impedance
towards 200 ohms and use a 4:1 balun by simply moving the feedpoint
some distance towards the center?

While that sounds like a good idea, it also shifts the frequencies where
the SWR is low, especially when trying to get it to work with low swr
over most of the ham bands below 30 MHz.

I could lower it to about 25 feet and use the 4:1 but I want it as high
as I can get it which is about 50 to 60 feet now.
Mostly flat as it is suported on the ends and near the middle around the
same heigth.

Part of the heigth is so I can use the Carolina Windom idea of using a
voltage balun and dropping from the feed point about 20 feet. and
putting in an in line choke. I don't know if it will work as they
say,but suspose to give some vertical radiation along with the
horizontal.

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