Re: cheap vertical


From: Larry Cahoon (
Date: Wed Dec 05 2001 - 16:46:08 CST

I did something like this on 20 meters once on a trip to the outer banks of
NC with tent poles. One observation was that with the tent poles with a 1
1/4 in diameter or so the whip I used for the final adjustment had a much
smaller effect that I expected. That meant I needed a longer whip to get
the SWR down than would seem right from the measurements. This effect
actually shows up in the antenna models where you have to take into account
in the dimensions the tapering of the element. In my case the size of the
element decreased so quickly from the tent poles to the whip it was almost
like I didn't even have the whip. Thus the need for a longer whip to
adjust for the tapering effect.

73 de Larry.............WD3P in MD

At 04:12 PM 12/5/2001 -0500, John Harper AE5X wrote:
>I used three 10-foot sections from Radio Shack for a 40m vertical. I drilled
>holes into the part where sections overlapped and screwed sheet metal screws
>into the holes to ensure a good electrical connection between sections. Then
>I used a hose clamp to fasten a 4' whip to the top section to make up the
>rest of the length required to resonate the antenna on the CW portion of the
>band. The whole thing then sat on a glass Coke bottle and was guyed with
>nylon cord at the 20' level. It worked great with eight 1/4-wave radials.
>John Harper AE5X
>Outdoor QRP & Lowband DXing:

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