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A typical 1/4 wave whip will have an input impedance somewhere around 35 ohms give or take a bit. That means that the best SWR you could get is something like a 1.5:1. That's not just on 11 meters but on any band. If you want to keep an antenna resonant (a biggy), then changing it's length to change SWR is shooting your self in the foot. There's no significant difference between a 1.5:1 and the ideal 1:1 SWR, just not worth messing with.
Laying a not 1:1 SWR off on the 'groundplane' is sort of silly. At HF there isn't goping to be 'enough' vehicle to make a decent 'other half' (the 'groundplane) of that whip antenna to start with. And the vehicle isn't the onl;y thing that's making up that 'other half' of the antenna! The dirt/concrete/whatever under that vehicle also plays a part in it. So how can you tell what the antrenna is actually doing as far as resonance and impedance matching goes? Sorry, you can't do that with only an SWR meter. That SWR meter can't tell you what you need to know to 'correct' things. It never has and it never will. It can certainly tell you a little about what your antenna is doing, but only if you know a lot about what impedance actually is and what SWR actually is. It ain't simple! If you use an SWR meter to tune an antenna you will probably have as good an antenna as anyone else who does it that way. That does not mean that it's as good as it can get. Nasty thought? Yep, but it's a fact anyway...
- 'Doc

<blockquote data-quote="W5LZ" data-source="post: 454793" data-attributes="member: 129">A typical 1/4 wave whip will have an input impedance somewhere around 35 ohms give or take a bit.&nbsp; That means that the best SWR you could get is something like a 1.5:1.&nbsp; That&#039;s not just on 11 meters but on any band.&nbsp; If you want to keep an antenna resonant (a biggy), then changing it&#039;s length to change SWR is shooting your self in the foot.&nbsp; There&#039;s no significant difference between a 1.5:1 and the ideal 1:1 SWR, just not worth messing with.Laying a not 1:1 SWR off on the &#039;groundplane&#039; is sort of silly.&nbsp; At HF there isn&#039;t goping to be &#039;enough&#039; vehicle to make a decent &#039;other half&#039; (the &#039;groundplane) of that whip antenna to start with.&nbsp; And the vehicle isn&#039;t the onl;y thing that&#039;s making up that &#039;other half&#039; of the antenna!&nbsp; The dirt/concrete/whatever under that vehicle also plays a part in it.&nbsp; So how can you tell what the antrenna is actually doing as far as resonance and impedance matching goes?&nbsp; Sorry, you can&#039;t do that with only an SWR meter.&nbsp; That SWR meter can&#039;t tell you what you need to know to &#039;correct&#039; things.&nbsp; It never has and it never will.&nbsp; It can certainly tell you a little about what your antenna is doing, but only if you know a lot about what impedance actually is and what SWR actually is.&nbsp; It ain&#039;t simple!&nbsp; If you use an SWR meter to tune an antenna you will probably have as good an antenna as anyone else who does it that way.&nbsp; That does not mean that it&#039;s as good as it can get.&nbsp; Nasty thought?&nbsp; Yep, but it&#039;s a fact anyway...&nbsp;- &#039;Doc</blockquote>

[QUOTE="W5LZ, post: 454793, member: 129"] A typical 1/4 wave whip will have an input impedance somewhere around 35 ohms give or take a bit. That means that the best SWR you could get is something like a 1.5:1. That's not just on 11 meters but on any band. If you want to keep an antenna resonant (a biggy), then changing it's length to change SWR is shooting your self in the foot. There's no significant difference between a 1.5:1 and the ideal 1:1 SWR, just not worth messing with. Laying a not 1:1 SWR off on the 'groundplane' is sort of silly. At HF there isn't goping to be 'enough' vehicle to make a decent 'other half' (the 'groundplane) of that whip antenna to start with. And the vehicle isn't the onl;y thing that's making up that 'other half' of the antenna! The dirt/concrete/whatever under that vehicle also plays a part in it. So how can you tell what the antrenna is actually doing as far as resonance and impedance matching goes? Sorry, you can't do that with only an SWR meter. That SWR meter can't tell you what you need to know to 'correct' things. It never has and it never will. It can certainly tell you a little about what your antenna is doing, but only if you know a lot about what impedance actually is and what SWR actually is. It ain't simple! If you use an SWR meter to tune an antenna you will probably have as good an antenna as anyone else who does it that way. That does not mean that it's as good as it can get. Nasty thought? Yep, but it's a fact anyway... - 'Doc [/QUOTE]

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