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So far so good, but not always feasible. Honestly a HT unit with an antenna adapter output is useful for this...

Here is where you went wrong. The radio will have no effect on SWR. SWR meters simply compare the voltage (actually most use current, same results so no biggie) going in one direction, and compare to the voltage (or current) going in the other direction. Changing the components in the radio can change the voltage or current output, but they will not affect the ratio of forward to reflected power. I've actually done an experiment that has confirmed this in the past (there is a thread on this forum somewhere about it).

And back to the good info. Coax will make SWR appear to be better than it is. 100' of RG-58 can make a 4.5:1 SWR appear to be lower than 1.5:1 SWR, numbers come from a direct measurement in the past (another old thread somewhere on this forum, even older than the last one I mentioned...). Higher quality coax takes more length for a similar effect. If adding a few feet of coax makes your SWR go up, or significantly change in any direction then you have a problem somewhere that need to be dealt with.

The DB

<blockquote data-quote="The DB" data-source="post: 557973" data-attributes="member: 21346">So far so good, but not always feasible.&nbsp; Honestly a HT unit with an antenna adapter output is useful for this...Here is where you went wrong.&nbsp; The radio will have no effect on SWR.&nbsp; SWR meters simply compare the voltage (actually most use current, same results so no biggie) going in one direction, and compare to the voltage (or current) going in the other direction.&nbsp; Changing the components in the radio can change the voltage or current output, but they will not affect the ratio of forward to reflected power.&nbsp; I&#039;ve actually done an experiment that has confirmed this in the past (there is a thread on this forum somewhere about it).And back to the good info.&nbsp; Coax will make SWR appear to be better than it is.&nbsp; 100&#039; of RG-58 can make a 4.5:1 SWR appear to be lower than 1.5:1 SWR, numbers come from a direct measurement in the past (another old thread somewhere on this forum, even older than the last one I mentioned...).&nbsp; Higher quality coax takes more length for a similar effect.&nbsp; If adding a few feet of coax makes your SWR go up, or significantly change in any direction then you have a problem somewhere that need to be dealt with.<a href="http://hittman.us" target="_blank">The DB</a></blockquote>

[QUOTE="The DB, post: 557973, member: 21346"] So far so good, but not always feasible. Honestly a HT unit with an antenna adapter output is useful for this... Here is where you went wrong. The radio will have no effect on SWR. SWR meters simply compare the voltage (actually most use current, same results so no biggie) going in one direction, and compare to the voltage (or current) going in the other direction. Changing the components in the radio can change the voltage or current output, but they will not affect the ratio of forward to reflected power. I've actually done an experiment that has confirmed this in the past (there is a thread on this forum somewhere about it). And back to the good info. Coax will make SWR appear to be better than it is. 100' of RG-58 can make a 4.5:1 SWR appear to be lower than 1.5:1 SWR, numbers come from a direct measurement in the past (another old thread somewhere on this forum, even older than the last one I mentioned...). Higher quality coax takes more length for a similar effect. If adding a few feet of coax makes your SWR go up, or significantly change in any direction then you have a problem somewhere that need to be dealt with. [URL='http://hittman.us'][COLOR=#000000]The DB[/COLOR][/URL] [/QUOTE]

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