[Elecraft] Can I measure antenna impedance with K2?

[Per-Tore Aasestrand]

Hi Matt,

> Of course you realise that the output impedance of the ATU will be the
> complex conjugate of the impedance at the rig end of your feedline.

I wonder if this is correct

IMO, the task of the tuner is to make the tx happy, so it can look into the
load it is designed for. Thus, it will translate the impedance as seen from
the antenna connector into something as close to 50 ohm as possible. The
tuner will not change anything on the feeder. With or without the tuner,
the feeder will have the same VSWR.

Per-Tore / LA7NO




On 31 July 2014 22:02, Matt VK2RQ <matt.vk2rq at gmail.com> wrote:

> Of course you realise that the output impedance of the ATU will be the
> complex conjugate of the impedance at the rig end of your feedline.
> However, if you want to know the impedance of your antenna, you need to
> realise that the feedline is acting as an impedance transformer, and you
> need to take into account factors such as length of feedline, frequency of
> operation characteristic impedance and velocity factor of the feedline,
> etc..
>
> 73, Matt VK2RQ
>
> > On 1 Aug 2014, at 1:02 am, TF3KX <kristinn1 at gmail.com> wrote:
> >
> > Thanks. Yes, I can determine the tuner settings (L/C-values, etc.) and
> from
> > the network equations derive the impedance these settings match into. It
> > would be neat if the K2 had enough CPU power and memory to carry these
> > calculations out for me and just display the R+jX. Perhaps a good project
> > for a small program or an app...
> >
> > 73 - Kristinn, TF3KX
> >
> >
> >
> > --
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