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Eddie
we know that in the real world an a99 works & shows a low vswr on an analyzer with no mast so there must be enough conductor for return currents using the short coax & mounting tube to keep kirchhoff happy even when the a99 has no mast or coax braid,

a99 & imax have a foot or so of coax with a foot or so of tube folded back over it, the top of the mounting stub near the rings is a couple of feet or more away from the feed-point electrically,

so its not exactly the same as a model with only a matching transformer that can only use the mast or your coax braid for return currents because they are the only conductors available,

that does not mean 1/2wave end-feds are immune to cmc,

give it a low impedance path for return currents & any end-fed can have cmc on the mast or feed-line that spoils the pattern & more important nowadays picks up more local noise than you would like,

The low gain model looks like a 1wavelength dipole,

"END-FED antenna"

Disambiguation,
The known electrical length of ONE part of an antenna system with an unknown electrical length.

<blockquote data-quote="bob85" data-source="post: 734661" data-attributes="member: 18">Eddiewe know that in the real world an a99 works &amp; shows a low vswr on an analyzer with no mast so there must be enough conductor for return currents using the short coax &amp; mounting tube to keep kirchhoff happy even when the a99 has no mast or coax braid,a99 &amp; imax have a foot or so of coax with a foot or so of tube folded back over it, the top of the mounting stub near the rings is a couple of feet or more away from the feed-point electrically,so its not exactly the same as a model with only a matching transformer that can only use the mast or your coax braid for return currents because they are the only conductors available,that does not mean 1/2wave end-feds are immune to cmc,give it a low impedance path for return currents &amp; any end-fed can have cmc on the mast or feed-line that spoils the pattern &amp; more important nowadays picks up more local noise than you would like,The low gain model looks like a 1wavelength dipole,&quot;END-FED antenna&quot;Disambiguation,The known electrical length of ONE part of an antenna system with an unknown electrical length.</blockquote>

[QUOTE="bob85, post: 734661, member: 18"] Eddie we know that in the real world an a99 works & shows a low vswr on an analyzer with no mast so there must be enough conductor for return currents using the short coax & mounting tube to keep kirchhoff happy even when the a99 has no mast or coax braid, a99 & imax have a foot or so of coax with a foot or so of tube folded back over it, the top of the mounting stub near the rings is a couple of feet or more away from the feed-point electrically, so its not exactly the same as a model with only a matching transformer that can only use the mast or your coax braid for return currents because they are the only conductors available, that does not mean 1/2wave end-feds are immune to cmc, give it a low impedance path for return currents & any end-fed can have cmc on the mast or feed-line that spoils the pattern & more important nowadays picks up more local noise than you would like, The low gain model looks like a 1wavelength dipole, "END-FED antenna" Disambiguation, The known electrical length of ONE part of an antenna system with an unknown electrical length. [/QUOTE]

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