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I think that something that people are 'missing' is that choke, that coil of feed line, only affects what's on the outside of that feed line, not what's on the inside of that feed line. The only significant affect a choke has on any feed line is that it adds some length to it. That can mean some loss because of resistance, but for the lengths commonly used to make up that choke, that resistance amounts to very, very little. Notice that I said 'resistance', not impedance. If the impedance of the -system- is changed because of that added length, then the antenna (load) on the end of that feed line is incorrectly tuned. Meaning that it is not the same impedance as the feed line and the transmitter. That holds true for any transfer of AC energy no matter it's frequency, 27 Mhz or 60 Hertz, or audio frequencies, anything AC.
- 'Doc

<blockquote data-quote="W5LZ" data-source="post: 342899" data-attributes="member: 129">I think that something that people are &#039;missing&#039; is that choke, that coil of feed line, only affects what&#039;s on the outside of that feed line, not what&#039;s on the inside of that feed line.&nbsp; The only significant affect a choke has on any feed line is that it adds some length to it.&nbsp; That can mean some loss because of resistance, but for the lengths commonly used to make up that choke, that resistance amounts to very, very little.&nbsp; Notice that I said &#039;resistance&#039;, not impedance.&nbsp; If the impedance of the -system- is changed because of that added length, then the antenna (load) on the end of that feed line is incorrectly tuned.&nbsp; Meaning that it is not the same impedance as the feed line and the transmitter.&nbsp; That holds true for any transfer of AC energy no matter it&#039;s frequency, 27 Mhz or 60 Hertz, or audio frequencies, anything AC.&nbsp;- &#039;Doc</blockquote>

[QUOTE="W5LZ, post: 342899, member: 129"] I think that something that people are 'missing' is that choke, that coil of feed line, only affects what's on the outside of that feed line, not what's on the inside of that feed line. The only significant affect a choke has on any feed line is that it adds some length to it. That can mean some loss because of resistance, but for the lengths commonly used to make up that choke, that resistance amounts to very, very little. Notice that I said 'resistance', not impedance. If the impedance of the -system- is changed because of that added length, then the antenna (load) on the end of that feed line is incorrectly tuned. Meaning that it is not the same impedance as the feed line and the transmitter. That holds true for any transfer of AC energy no matter it's frequency, 27 Mhz or 60 Hertz, or audio frequencies, anything AC. - 'Doc [/QUOTE]

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