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As per the title, all the photos are in the link
I did some googling some time back and found no info on how a coil between a 1/4 wave section and a 5/8 wave section will give the necessary 180 degrees of delay or if a coil can be used this way to make it work as a collinear
as we know a 1/4 wave antenna doesn't need a matching device nor does it if you lengthen it every multiple of a 1/2 a wave is 1/4 wave then 3/4 wave and so on
this antenna is 7/8 long overall.. is not the coil making it act like a 1-1/4 wave as far as matching is concerned by just adding inductance and nothing else
if the coil is giving it 180 delay its a cunningly simple design where a sample coil matches it to a 50 ohm and makes it a collinear at the same time
link
[URL unfurl="true"]https://www.grazioliantenne.com/en/prodotto/antenna-gmax/[/URL]

<blockquote data-quote="davev8" data-source="post: 829765" data-attributes="member: 19379">As per the title, all the photos are in the link&nbsp;I did some googling some time back and found no info on how a coil between a 1/4 wave section and a 5/8 wave section will give the necessary 180 degrees of delay&nbsp; or if a coil can be used this way to make it work as a collinearas we know a 1/4 wave antenna doesn&#039;t need a matching device nor does it if you lengthen it every multiple of a 1/2 a wave&nbsp;&nbsp; is 1/4 wave then 3/4 wave and so on&nbsp;this antenna is 7/8 long overall.. is not the coil making it act like a 1-1/4 wave as far as matching is concerned by just adding inductance and nothing else if the coil is giving it 180 delay its a cunningly simple design where a sample coil matches it to a 50 ohm and makes it a collinear at the same timelink [URL unfurl=&quot;true&quot;]https://www.grazioliantenne.com/en/prodotto/antenna-gmax/[/URL]</blockquote>

[QUOTE="davev8, post: 829765, member: 19379"] As per the title, all the photos are in the link I did some googling some time back and found no info on how a coil between a 1/4 wave section and a 5/8 wave section will give the necessary 180 degrees of delay or if a coil can be used this way to make it work as a collinear as we know a 1/4 wave antenna doesn't need a matching device nor does it if you lengthen it every multiple of a 1/2 a wave is 1/4 wave then 3/4 wave and so on this antenna is 7/8 long overall.. is not the coil making it act like a 1-1/4 wave as far as matching is concerned by just adding inductance and nothing else if the coil is giving it 180 delay its a cunningly simple design where a sample coil matches it to a 50 ohm and makes it a collinear at the same time link [URL unfurl="true"]https://www.grazioliantenne.com/en/prodotto/antenna-gmax/[/URL] [/QUOTE]

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