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Re: Topband: T-antenna dimensions?

To: Mike Waters W0BTU <mrscience65704@yahoo.com>,topband@contesting.com
Subject: Re: Topband: T-antenna dimensions?
From: "Richard L. King" <k5na@ecpi.com>
Date: Mon, 18 Jan 2010 14:49:28 +0000
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Mike.

I don't know if this helps, but I once had a T-top vertical here and 
it worked remarkably well. For resonance at 1830 the lengths were:

Vertical portion was 60 feet.
Horizontal (tophat) portion was 95 feet (attached in the middle).
Four raised radials at exactly 90 degree intervals.
Feed point was 6 feet off the ground.
NO ground rod was used at the feed point.
It was fed with a 1/4 wave 75 ohm series coaxial transformer to match 
low feed point impedance.

This was over very high ground conductivity, so that might make some 
difference.

You may have to do a little trial and error on the measurements. 
Start long and trim back.

Good luck.

73, Richard - K5NA



At 00:55 1/18/2010, Mike Waters W0BTU wrote:
>Now that I can hear very well (Two 2-wire bi-directional Beverages), 
>it's time for a transmitting antenna. I want to play in the contest 
>during January 29-31, and time is running out to put up a 
>transmitting antenna. I don't have a tower at this time.
>
>I have some trees picked out for a T antenna, between a section of 
>pasture where it's easy to lay down a lot of radials. I can have a 
>50' vertical section.
>
>But I'm having trouble finding what the approx. dimension of the 
>horizontal portion at the top should be. Any advice would be appreciated!
>
>73,
>Mike Waters
>W0BTU
>
>
>
>_______________________________________________
>UR RST IS ... ... ..9 QSB QSB - hw? BK
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK

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