Jim, I have an Rig Expert AA-200 analyser, which is excellent for this sort of
thing, shows a proper swr plot on the screen, better than the MFJ unit. On 80m
at 3637kHz, swr = 1.4:1, R 35.3, Z 35.3, X -2.3, C 19069pF on 1900kHz with the
loading coil in place, swr = 2.5:1, R 20.9, Z 22.9, X -9.3 C 9035pF. swr is >10
without the coil on 1900kHzThe weather has been dryish all week and when I did
the previous tests the weather had been wet for a week so ground conductivity
is almost certainly playing a part in this.
73 Max M0GHQ
> Date: Sat, 6 Jun 2015 08:32:06 -0700
> From: jim@audiosystemsgroup.com
> To: topband@contesting.com
> Subject: Re: Topband: Topband loading coil
>
>
> > Ideas what to do next
>
> Borrow an antenna analyzer and measure the antenna's feedpoint impedance
> with a very short piece of coax (in other words, right at the base) with
> and without the coil.
>
> 73, Jim K9YC
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