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Those 'CMC's traveling on the outside of the feed line. In the case of the 'A99' or Imaxx antennas, that outside of the feed line -is- the other half of the antenna, the 'groundplane', or 'counterpoise', or whatever you want to call it. That's for any "no-ground" antenna, not just those two. Get rid of -ALL- the CMC's on the outside of their feed lines and you just stopped that antenna system from working.

That TOA doesn't mean that there;s nothing above or below that particular angle, it only means that that TOA 'lobe' is where the most signal is. There's still plenty 'under' or directly below that antenna, and straight up too. Got a field strength meter? Go see for yourself. One common 'goof' made by almost everyone is the 'scale' of those radiation patterns. The boundaries, the outer edges, are much further than they appear from the antenna's position. I don't think there's a printer or display screen that can make a 'dot' small enough to keep the scale of the antenna's size in relation to the signal's 'spread' even close to 'scale'.
How the feed line leaves the antenna, how it's positioned/shaped, is a factor in using any antenna with no "groundplane"/counterpoise/radials/whatever you want to call it's 'other half'. It can have a very pronounced affect on the 'shape' of that antenna's radiation pattern. Think about it...
- 'Doc

<blockquote data-quote="W5LZ" data-source="post: 299349" data-attributes="member: 129">Those &#039;CMC&#039;s traveling on the outside of the feed line.&nbsp; In the case of the &#039;A99&#039; or Imaxx antennas, that outside of the feed line -is- the other half of the antenna, the &#039;groundplane&#039;, or &#039;counterpoise&#039;, or whatever you want to call it.&nbsp; That&#039;s for any &quot;no-ground&quot; antenna, not just those two.&nbsp; Get rid of -ALL- the CMC&#039;s on the outside of their feed lines and you just stopped that antenna system from working.That TOA doesn&#039;t mean that there;s nothing above or below that particular angle, it only means that that TOA &#039;lobe&#039; is where the most signal is.&nbsp; There&#039;s still plenty &#039;under&#039; or directly below that antenna, and straight up too.&nbsp; Got a field strength meter?&nbsp; Go see for yourself.&nbsp; One common &#039;goof&#039; made by almost everyone is the &#039;scale&#039; of those radiation patterns.&nbsp; The boundaries, the outer edges, are much further than they appear from the antenna&#039;s position.&nbsp; I don&#039;t think there&#039;s a printer or display screen that can make a &#039;dot&#039; small enough to keep the scale of the antenna&#039;s size in relation to the signal&#039;s &#039;spread&#039; even close to &#039;scale&#039;.How the feed line leaves the antenna, how it&#039;s positioned/shaped, is a factor in using any antenna with no &quot;groundplane&quot;/counterpoise/radials/whatever you want to call it&#039;s &#039;other half&#039;.&nbsp; It can have a very pronounced affect on the &#039;shape&#039; of that antenna&#039;s radiation pattern.&nbsp; Think about it...&nbsp;- &#039;Doc</blockquote>

[QUOTE="W5LZ, post: 299349, member: 129"] Those 'CMC's traveling on the outside of the feed line. In the case of the 'A99' or Imaxx antennas, that outside of the feed line -is- the other half of the antenna, the 'groundplane', or 'counterpoise', or whatever you want to call it. That's for any "no-ground" antenna, not just those two. Get rid of -ALL- the CMC's on the outside of their feed lines and you just stopped that antenna system from working. That TOA doesn't mean that there;s nothing above or below that particular angle, it only means that that TOA 'lobe' is where the most signal is. There's still plenty 'under' or directly below that antenna, and straight up too. Got a field strength meter? Go see for yourself. One common 'goof' made by almost everyone is the 'scale' of those radiation patterns. The boundaries, the outer edges, are much further than they appear from the antenna's position. I don't think there's a printer or display screen that can make a 'dot' small enough to keep the scale of the antenna's size in relation to the signal's 'spread' even close to 'scale'. How the feed line leaves the antenna, how it's positioned/shaped, is a factor in using any antenna with no "groundplane"/counterpoise/radials/whatever you want to call it's 'other half'. It can have a very pronounced affect on the 'shape' of that antenna's radiation pattern. Think about it... - 'Doc [/QUOTE]

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