Paul,
Here is a handy on line calculator to help you determine the approx wire length.
You can play with putting in different freqs and see how much the wire length
changes.
I believe with frequency changes of 10KHZ the wire length changes by about one
foot.
So if it is resonant at 1.800 and you trim off one foot it will be resonant at
1.810.
Note that with the calculator, an inverted V has different lengths than a
horiz dipole
http://www.cdagro.com/dip/dpo.html
If you can find the resonant freq (where the lowest SWR is) then you can see
how far you have to move.
I find this calculator to be in the ball park. I normally cut the wire lengths
long to start with and then prune
till I bring the resonant freq up to where I want it to be. It sounds like
you are resonant below the band right now
which is good, prune time !
73,
K6UJ
Bob
On Oct 30, 2012, at 4:29 PM, paul ecker wrote:
>
>
> I put up a 160m dipole but now need to tune it. SWR at low end of band is abt
> 3 and at top end abt 5. From what I have read this means I need to shorten
> it. My question is how much should I take off? A foot off each end?? Any good
> links to sites that may explain this in some detail so I can learn?
>
> Tu and 73
> Paul
> kc2nyu
> _______________________________________________
> Topband reflector - topband@contesting.com
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Topband reflector - topband@contesting.com
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