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I visited this web site associated with the link shown in the previous post and read the article and download the software and NO WHERE DOES IT SAY ANYTHING ABOUT A "1/4 WAVE MATCHING STUB" being associated with the Super/Scanner type of antenna.
It talks about the feed lines going to their respective dipoles as being a 1/4 wave length but the Antenna Specialists Instructions that come with the antenna indicated that the feedlines are 29 inches long.
They are that long so that when in one of the directional modes the other two dipoles are loaded with the right amount of inductance that is provided by an open stub of that length for the purpose of making the those two elements appear to be longer so as to act as a reflector; But this is not what we are talking about, we are talking about the matching stub for the OMNI Posistion, and that stub length is not a 1/4 wavelength according to the Instruction book provided by Antenna Specialists and according to common sense it cannot be a 1/4 wavelength shorted stub.

Like I said in a previous post in this thread; A shorted 1/4 wave is zero Z at the shorted end and extremely HI Z at the open end.

If you look at the schematic for this antenna the 3/8 wavelength stub is in shunt with the 3 dipoles when in the OMNI mode.

A 1/4 wave shorted stub would present an impedance so high that it would effectively do NOTHING.

Additionally you say a "SERIES" capacitor; It is not in series, it is in parallel with the inductor and then that is in shunt (parallel) with the 3 dipoles when it is in the OMNI mode.

<blockquote data-quote="RADIOOMAN" data-source="post: 414845" data-attributes="member: 25990"><a href="http://www.ve3sqb.com/" target="_blank"></a><a href="http://www.ve3sqb.com/" target="_blank"></a><a href="http://www.ve3sqb.com/" target="_blank">I visited this web site associated with the link shown in the previous post and read the article and download the software and NO WHERE DOES IT SAY ANYTHING ABOUT A &quot;1/4 WAVE MATCHING STUB&quot; being associated with the Super/Scanner type of antenna.</a><a href="http://www.ve3sqb.com/" target="_blank">It talks about the feed lines going to their respective dipoles as being a 1/4 wave length but the Antenna Specialists Instructions that come with the antenna indicated that the feedlines are 29 inches long.</a><a href="http://www.ve3sqb.com/" target="_blank">They are that long so that when in one of the directional modes the other two dipoles are loaded with the right amount of inductance that is provided by an open stub of that length for the purpose of making the those two elements appear to be longer so as to act as a reflector; But this is not what we are talking about, we are talking about the matching stub for the OMNI Posistion, and that stub length is not a 1/4 wavelength according to the Instruction book provided by Antenna Specialists and according to common sense it cannot be a 1/4 wavelength shorted stub.</a><a href="http://www.ve3sqb.com/" target="_blank"></a><a href="http://www.ve3sqb.com/" target="_blank">Like I said in a previous post in this thread; A shorted 1/4 wave is zero Z at the shorted end and extremely HI Z at the open end.</a><a href="http://www.ve3sqb.com/" target="_blank"></a><a href="http://www.ve3sqb.com/" target="_blank">If you look at the schematic for this antenna the 3/8 wavelength stub is in shunt with the 3 dipoles when in the OMNI mode.</a><a href="http://www.ve3sqb.com/" target="_blank"></a><a href="http://www.ve3sqb.com/" target="_blank">A 1/4 wave shorted stub would present an impedance so high that it would effectively do NOTHING.</a><a href="http://www.ve3sqb.com/" target="_blank"></a><a href="http://www.ve3sqb.com/" target="_blank">Additionally you say a &quot;SERIES&quot; capacitor; It is not in series, it is in parallel with the inductor and then that is in shunt (parallel) with the 3 dipoles when it is in the OMNI mode.</a></blockquote>

[QUOTE="RADIOOMAN, post: 414845, member: 25990"] [url=http://www.ve3sqb.com/] [SIZE="3"]I visited this web site associated with the link shown in the previous post and read the article and download the software and NO WHERE DOES IT SAY ANYTHING ABOUT A "1/4 WAVE MATCHING STUB" being associated with the Super/Scanner type of antenna. It talks about the feed lines going to their respective dipoles as being a 1/4 wave length but the Antenna Specialists Instructions that come with the antenna indicated that the feedlines are 29 inches long. They are that long so that when in one of the directional modes the other two dipoles are loaded with the right amount of inductance that is provided by an open stub of that length for the purpose of making the those two elements appear to be longer so as to act as a reflector; But this is not what we are talking about, we are talking about the matching stub for the OMNI Posistion, and that stub length is not a 1/4 wavelength according to the Instruction book provided by Antenna Specialists and according to common sense it cannot be a 1/4 wavelength shorted stub. Like I said in a previous post in this thread; A shorted 1/4 wave is zero Z at the shorted end and extremely HI Z at the open end. If you look at the schematic for this antenna the 3/8 wavelength stub is in shunt with the 3 dipoles when in the OMNI mode. A 1/4 wave shorted stub would present an impedance so high that it would effectively do NOTHING. Additionally you say a "SERIES" capacitor; It is not in series, it is in parallel with the inductor and then that is in shunt (parallel) with the 3 dipoles when it is in the OMNI mode.[/SIZE][/url] [/QUOTE]

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