Topband: Tuning 160M Dipole

[Bob K6UJ]

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 at contesting.com