[TowerTalk] SWR problems on 20M dipoles?

[DavidC]

> ... the 20m inverted vee has a 
> 3.5:1 SWR.  However, that 3.5:1 occurs around 14260, and on either side 
> of that, the SWR goes up to 4.5 or 5:1 on the band edges.  This seems to 
> act like it is resonant on 14260.  We have checked for anything touching 
> the wire on the end insulators, and also the center, which is up around 
> 35 feet.  On the center, the only thing that could possibly be touching 
> is a real narrow piece of string which doesn't appear to be 
> touching...appears only to be touching the center insulator.
> 
> We have checked the coax for a short, and there wasn't one.
> A little background on the antenna:
> 
> It was up previously, resonant right around 14270, and had been working 
> fine.  Then one support fell and we just put it back up today in the 
> same spot it had been.  Now we have the SWR problem that wasn't there 
> before.
> 
> Any suggestions as to what could cause this?
> Thanks and 73  David Jones, KK7GW   

Is it possible that the side with the fallen and restored support was
stretched during that event and now the dipole is imbalanced?  Or perhaps
the connection at the feedpoint has been disturbed to the point that the
solder joint has been compromised?  Will be interested to learn what you do
discover!  73, DavidC  AA1FA


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