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I see similar types of gain values in the regular CB antennas too, all except for the Gain Master.

Bob I can't get your idea with the feed point at the base of your A/P 3/4 wave antenna to show a good match...without the use of some form of matching device.

FWIU the tap point on a 3/4 wave radiator at 27 mhz is about 30" - 33" above the base, and no altering of the two down radials, to make the radials closer to the mast, or bowing a little bit toward the mast will work to overcome this mismatch...like it does on the A/P. However, the 3/4 wave radiator with 2 slanted up radials that are straight will work perfectly well and give a good match if the hub is smaller than the A/P, and we use a gamma match.

I found the best compromise offset hub size for my model's radials from the base of the radiator is 3/4" of an inch offset on both sides connected to the radials, and less is worse and more is worse.

[ATTACH]11338[/ATTACH]

<blockquote data-quote="Marconi" data-source="post: 445405" data-attributes="member: 903">I see similar types of gain values in the regular CB antennas too, all except for the Gain Master. &nbsp;Bob I can&#039;t get your idea with the feed point at the base of your A/P 3/4 wave antenna to show a good match...without the use of some form of matching device. &nbsp;FWIU the tap point on a 3/4 wave radiator at 27 mhz is about 30&quot; - 33&quot; above the base, and no altering of the two down radials, to make the radials closer to the mast, or bowing a little bit toward the mast will work to overcome this mismatch...like it does on the A/P. However, the 3/4 wave radiator with 2 slanted up radials that are straight will work perfectly well and give a good match if the hub is smaller than the A/P, and we use a gamma match.&nbsp;I found the best compromise offset hub size for my model&#039;s radials from the base of the radiator is 3/4&quot; of an inch offset on both sides connected to the radials, and less is worse and more is worse. &nbsp;[ATTACH]11338[/ATTACH]</blockquote>

[QUOTE="Marconi, post: 445405, member: 903"] [COLOR=black][FONT=Verdana][SIZE=1][/SIZE][/FONT][/COLOR]I see similar types of gain values in the regular CB antennas too, all except for the Gain Master. [COLOR=black][FONT=Verdana][SIZE=1][/SIZE][/FONT][/COLOR][COLOR=black][FONT=Verdana][SIZE=1]Bob I can't get your idea with the feed point at the base of your A/P 3/4 wave antenna to show a good match...without the use of some form of matching device. [/SIZE][/FONT][/COLOR] [COLOR=black][FONT=Verdana][SIZE=1][/SIZE][/FONT][/COLOR] [COLOR=black][FONT=Verdana][SIZE=1]FWIU the tap point on a 3/4 wave radiator at 27 mhz is about 30" - 33" above the base, and no altering of the two down radials, to make the radials closer to the mast, or bowing a little bit toward the mast will work to overcome this mismatch...like it does on the A/P. However, the 3/4 wave radiator with 2 slanted up radials that are straight will work perfectly well and give a good match if the hub is smaller than the A/P, and we use a gamma match.[/SIZE][/FONT][/COLOR] [COLOR=black][FONT=Verdana][SIZE=1]I found the best compromise offset hub size for my model's radials from the base of the radiator is 3/4" of an inch offset on both sides connected to the radials, and less is worse and more is worse.[/SIZE][/FONT][/COLOR] [ATTACH]11338.vB[/ATTACH] [/QUOTE]

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