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"Properly placed, they (capacitance hats) can effectively increase the electrical length, by moving the current maxima toward the center of the antenna.

Tech Talk: . . . the following assumes the cap hat is mounted at the very top of the antenna, and thus the noted increase in input impedance is a positive one, not a negative one.

Because the effective electrical length is increased, the radiation resistance also increases, albeit slightly. Physically increasing the whip length will do the same, but there is a practical limit to how long an HF mobile antenna can be (height above ground). By adding a cap hat, the overall length can remain the same (or less if the cap hat is large enough), while radiation resistance increases. " http://www.k0bg.com/caphats.html

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<blockquote data-quote="HomerBB" data-source="post: 265388" data-attributes="member: 8569">&quot;Properly placed, they (capacitance hats) can effectively increase the electrical length, by moving the current maxima toward the center of the antenna.&nbsp; &nbsp; Tech Talk:&nbsp; . . . the following assumes the cap hat is mounted at the very top of the antenna, and thus the noted increase in input impedance is a positive one, not a negative one.Because the effective electrical length is increased, the radiation resistance also increases, albeit slightly. Physically increasing the whip length will do the same, but there is a practical limit to how long an HF mobile antenna can be (height above ground). By adding a cap hat, the overall length can remain the same (or less if the cap hat is large enough), while radiation resistance increases. &quot; <a href="http://www.k0bg.com/caphats.html" target="_blank">http://www.k0bg.com/caphats.html</a>?</blockquote>

[QUOTE="HomerBB, post: 265388, member: 8569"] [I][B]"Properly placed, they (capacitance hats) can effectively increase the electrical length, by moving the current maxima toward the center of the antenna. Tech Talk: . . . the following assumes the cap hat is mounted at the very top of the antenna, and thus the noted increase in input impedance is a positive one, not a negative one. Because the effective electrical length is increased, the radiation resistance also increases, albeit slightly. Physically increasing the whip length will do the same, but there is a practical limit to how long an HF mobile antenna can be (height above ground). By adding a cap hat, the overall length can remain the same (or less if the cap hat is large enough), while radiation resistance increases. "[/B][/I] [URL="http://www.k0bg.com/caphats.html"]http://www.k0bg.com/caphats.html[/URL] [B][SIZE="5"]?[/SIZE][/B] [/QUOTE]

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