[Antennas] New OCF Dipole

[Charles Greene]

Bill

I don't think a t200-2 has eno[ugh permeability for a balun on 80 
meters,   That might be your prob.  My Ocf is > 2:1 across the 80 
meter band using those dimensions.  Try a 4:1 balun using a f140-43 
core, of better yet, two.

Chas W1CG

At 08:26 AM 3/12/2008, William A Kulze wrote:
>A week or so ago I saw a posting here regarding an OCF Dipole. I started
>digging into the links, and finally built one based on the plans in the
>ARRL Antenna book. I made a 4:1 balun on a T200-2 toroid and measured out
>the legs per the book. Hoisted it up on a temporary mast (poor thing looks
>really cobbed together) with a feedpoint height of about 15ft. The ends at
>about 8ft. Right off the bat I had a match on the even harmonics (I just
>realized I haven't checked the odd harmonics yet). But it was high on 75m.
>Well, it was 2:1, but my radio, IC-735, recommends not transmitting into
>more than a 1.5:1 for some reason. It was much better at the low end of
>80m. I twisted some 1kV caps together to make about 250pf total and put it
>in series with the long leg. Brought my 1.5:1 point up to about 3900kHz.
>So, next step is more capacitance to give me all 80m/75m. From the reports
>I got last night, This should be a good performer once I get it up to
>working height, about 35ft center, 10 ft ends. Of course, this was on 75m,
>so it might not be as good if it goes up higher.
>
>I'm a new ham and went straight into general. I'm having a blast. Who
>would have thought you could just apply some theory and actually get
>results?! And I'm learning alot in the process.
>
>Thanks to everybody out there. This is a great resource.
>
>Bill KC2SUO
>
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