Question re: 1/4 Wave Ground Plane Measurements

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Dogen
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Question re: 1/4 Wave Ground Plane Measurements

Post by Dogen »

I am making a simple 1/4 wave ground plane antenna and have two rather silly question regarding its measurements.

1. I've attached an SO-239 connecter to a 5x5 inch aluminum plate. When measuring the radial length, I measure from the center conductor of the SO-239 to the end of the radial taking into account the plate, correct?

2. If I make a loop in the vertical radiating element so that I may hang the antenna, does the circumference of the loop count in the measurement of the element or the diameter? (e.g., if I need 28.5 inches for the element, do I measure from the bottom of the SO-239 to the top of the loop or do I take a 28.5 inch wire and make a loop not caring that it has shortened the element slightly?)

Thanks,

Dogen
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pcs
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Post by pcs »

The loop at the top will add a bit to the overall length of the radiating element, but not as much as
it would if you unwound it. Maybe 20-50%

The best you can do is: Get a SWR meter and check it.
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