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The original AP is a 3/4 wave with the lower inverse-phase 1/4 wave folded up to rephase it and the top 1/4 wave finished by using a capacitance hat.

The original objective was to produce a full 1/2 wave radiator without a lossy matching network which is usually required (for what is typically about a 2500ohm load) and with the high current node as high as possible within the FCC's 20' max above the roof limits.

If you take the 30' dia hoop and multiply it x pi then take 1/2 that (plus 1/2 the tubing circumference) for the dual current path, you'll end up with right at 48" (4') plus 7' x 2 down each side to the ring.

7' +7' = 14' + 4' = 1/2 wave (18') plus the top cap hat loaded 1/4 wave = 3/4 wave total, or the only other antenna except for a 1/4 wave which can provide right about a 50om load when driven directly.

The counterpoise is the mast.

Ingenious, really.

Am I mistaken in thinking I remember a 3/4 wave provides about 6db high-angle gain? I wonder what happens when it's lower 1/4 wave is folded back up alongside the next 1/4 wave up with an odd shape keeping the counterpoise well away from the high voltage node of the radiator?

- Marconi?

<blockquote data-quote="Needle Bender" data-source="post: 364764" data-attributes="member: 13339">The original AP is a 3/4 wave with the lower inverse-phase 1/4 wave folded up to rephase it and the top 1/4 wave finished by using a capacitance hat. The original objective was to produce a full 1/2 wave radiator without a lossy matching network which is usually required (for what is typically about a 2500ohm load) and with the high current node as high as possible within the FCC&#039;s 20&#039; max above the roof limits.If you take the 30&#039; dia hoop and multiply it x pi then take 1/2 that (plus 1/2 the tubing circumference) for the dual current path, you&#039;ll end up with right at 48&quot; (4&#039;) plus 7&#039; x 2 down each side to the ring. 7&#039; +7&#039; = 14&#039; + 4&#039; = 1/2 wave (18&#039;) plus the top cap hat loaded 1/4 wave = 3/4 wave total, or the only other antenna except for a 1/4 wave which can provide right about a 50om load when driven directly.The counterpoise is the mast.Ingenious, really.Am I mistaken in thinking I remember a 3/4 wave provides about 6db high-angle gain? I wonder what happens when it&#039;s lower 1/4 wave is folded back up alongside the next 1/4 wave up with an odd shape keeping the counterpoise well away from the high voltage node of the radiator?&nbsp;- Marconi?<img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f914.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":huh:" title="Unsure&nbsp; &nbsp; :huh:"&nbsp; data-smilie="28"data-shortname=":huh:" /></blockquote>

[QUOTE="Needle Bender, post: 364764, member: 13339"] The original AP is a 3/4 wave with the lower inverse-phase 1/4 wave folded up to rephase it and the top 1/4 wave finished by using a capacitance hat. The original objective was to produce a full 1/2 wave radiator without a lossy matching network which is usually required (for what is typically about a 2500ohm load) and with the high current node as high as possible within the FCC's 20' max above the roof limits. If you take the 30' dia hoop and multiply it x pi then take 1/2 that (plus 1/2 the tubing circumference) for the dual current path, you'll end up with right at 48" (4') plus 7' x 2 down each side to the ring. 7' +7' = 14' + 4' = 1/2 wave (18') plus the top cap hat loaded 1/4 wave = 3/4 wave total, or the only other antenna except for a 1/4 wave which can provide right about a 50om load when driven directly. The counterpoise is the mast. Ingenious, really. Am I mistaken in thinking I remember a 3/4 wave provides about 6db high-angle gain? I wonder what happens when it's lower 1/4 wave is folded back up alongside the next 1/4 wave up with an odd shape keeping the counterpoise well away from the high voltage node of the radiator? - Marconi? :huh: [/QUOTE]

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