The Inv L over a very dense, excellent radial field will have a feed Z of
in the neighborhood of 20 or so ohms, NOT 50. It usually requires a unun
to bring it up to 50.
When you first put it up, your counterpoise system was, to put it bluntly,
awful, and apparently a very lossy series resistance around 30 ohms. If I
read your text correctly, your counterpoise system consisted of the outside
of your feed coax shield. As you are improving your counterpoise system
by adding radials and grounds, the 30 ohms plain loss is shrinking,
improving radiation, but making SWR worse, as the SUM of 20 ohms radiation
resistance AND the loss resistance of the counterpoise system becomes less
and less moving toward 20.
One of the many circumstances where low SWR is not an indicator of quality.
73, Guy.
On Fri, Dec 9, 2011 at 6:36 PM, Dan Bookwalter <n8dcj@yahoo.com> wrote:
> I installed an Inv-L for 160 of about 134ft , ~72 feet vertical , when i
> checked the SWR initially it was about 1.2:1 , then when i connected the
> ground rods it rose to 1.5:1 , today I added the first 2 radials and the
> SWR is now 2:1. The antenna is being fed directly , my question is
> basically what is this telling me ? I assume I need to change the way I am
> feeding the antenna and possibly change its length.
>
> any help appreciated...
>
> Dan N8DCJ
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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