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If you "tune the coax" for the freq by adjusting the length of the coax you may be fooling yourself. Then your coax may be acting as a part of the antenna and not as a feedline. RF current make strange things happen to high powered systems when coax act as a part of the antenna and not as a feedline.

Otherwise swr and reflect is as easy as matching impedances regardless of what power one use. If your system is correct and you have 1.1:1 on 4w of power you should have no problem with 2000w as long as the feedline and antenna are constructed to cope with it. You will only have a low rise on the swr. This is of course when everything is perfect, and very seldom it is. Most of us are very happy with our 1:1 readings.
The reality is often between 1:3-1:7.

I have 7 quality meters of several brands, Zetagi, Avair, MFJ, Ameritron, Watson. Not one of those give the same readings when measuring swr lower than 1,8 and theese are quite expensive meters.

btw: swr is a very uncertain reason to make a quarrel of

<blockquote data-quote="20CB110" data-source="post: 74518" data-attributes="member: 2112">If you &quot;tune the coax&quot; for the freq by adjusting the length of the coax you may be fooling yourself. Then your coax may be acting as a part of the antenna and not as a feedline. RF current make strange things happen to high powered systems when coax act as a part of the antenna and not as a feedline.Otherwise swr and reflect is as easy as matching impedances regardless of what power one use. If your system is correct and you have 1.1:1 on 4w of power you should have no problem with 2000w as long as the feedline and antenna are constructed to cope with it. You will only have a low rise on the swr. This is of course when everything is perfect, and very seldom it is. Most of us are very happy with our 1:1 readings.The reality is often between 1:3-1:7.I have 7 quality meters of several brands, Zetagi, Avair, MFJ, Ameritron, Watson. Not one of those give the same readings when measuring swr lower than 1,8 and theese are quite expensive meters.btw: swr is a very uncertain reason to make a quarrel of</blockquote>

[QUOTE="20CB110, post: 74518, member: 2112"] If you "tune the coax" for the freq by adjusting the length of the coax you may be fooling yourself. Then your coax may be acting as a part of the antenna and not as a feedline. RF current make strange things happen to high powered systems when coax act as a part of the antenna and not as a feedline. Otherwise swr and reflect is as easy as matching impedances regardless of what power one use. If your system is correct and you have 1.1:1 on 4w of power you should have no problem with 2000w as long as the feedline and antenna are constructed to cope with it. You will only have a low rise on the swr. This is of course when everything is perfect, and very seldom it is. Most of us are very happy with our 1:1 readings. The reality is often between 1:3-1:7. I have 7 quality meters of several brands, Zetagi, Avair, MFJ, Ameritron, Watson. Not one of those give the same readings when measuring swr lower than 1,8 and theese are quite expensive meters. btw: swr is a very uncertain reason to make a quarrel of [/QUOTE]

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