Hi allLast year i install an inverted L antenna for 160 with few radials
different lenght.ohms was between 20 to 25 ohms and swr about 2.2 . This past
weekend i was checking thethe antenna with the mfj analyser and i proceed to
disconnect the radials from the groundrod and just leave the ground
This is normal, but without the radials your RF is mostly heating up
the earth.
If you make the L a little longer, then insert a variable capacitor at
the feed point, you should be able to find a higher feed point with the
radials connected..
With trial and error 'juggling' the extra wire
On Thu, Dec 1, 2016 at 2:59 PM, james soto via Topband <
topband@contesting.com> wrote:
> i proceed to disconnect the radials from the groundrod and just leave the
> ground portion of the coax attach to the ground rod and the reading wasSWR
> 1.2 and 50 ohms. are this normal ?
Yup, and some very
As you were disconnecting the radials the ground losses were increasing
until it got to enough ohms and you had a good match at 50ohms.
My 160 T matches 25 ohms 1.12:1 at 1812Khz and is fed with a 50:25
transmission line transformer. With 8x 125' elevated radials the N6LF
research shows I hav
match, no parts required.
Many 40M shortened yagis use this method.
73,
Drew K3PA
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Message: 6
Date: Thu, 1 Dec 2016 16:53:53 -0800
From: Grant Saviers
To: james soto , Topband
Subject: Re: Topband: Inverted L Radials
Message-ID: <5840c621.6000...@pacbell
My planned inverted L has morphed a bit ... I modeled it – it is planned as a
95 – 100’ vertical section (depends on the amount of droop I can remove from a
~400’ line from the top guy ring at 122’ to a tree that is about 45’ high –
spaced about 100’ from the tower) ... I found that the angle in