If you cal and measure at the rig end, that will indicate the antenna
impedance as altered by the length of coax. If you cal at the end antenna
end of the coax and them measure at the rig end, that will give you the
impedance of the antenna as you have included the coax length in your cal.
We term this the location of the 'measurement plane'. If you measure at
the rig end and knowing the length of coax (which you do) and the coax type
(likely RG-58) for the velocity factor (likely 0.67), you can use SimSmith
to 'take out' the impedance transformative characteristics of the coax run.
Dave - W?LEV
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On Tue, Jan 28, 2020 at 3:57 PM <nanovnauser@...> wrote:
Hi all,ive a antenna consisting of 2 80m mobile whips in a dipole
configuration as i dont have room for anything else,i get different
readings on both my analysers,the antenna is at the end of a 60ft run of
coax,is it better to cal the vna by putting the cal load and short etc at
the end of the cable run,ie where the coax joins the antenna?,thanks in
advance.73
--
*Dave - W?LEV*
*Just Let Darwin Work*
*Just Think*
