"Owen Duffy" wrote in message
...

I am working with some guys on ambient noise measurement in a pre BPL
scenario.

They are using FSM ( http://www.vk1od.net/fsm/ ) to make field
strength measurements using a known comms receiver and a Carolina
Windom (CW).

We need to form a view on the CW antenna system losses (radiator,
ground reflection, isolator, matching unit, feedline, ATU.

Has anyone built and calibrated NEC models for the CW, or have they
measured reliably feedpoint impedance on the various bands.

This is not a troll, and I don't want to excite a war over the claimed
performance of the CW, I am not interested in anecdotal evidence or
QSO evidence as to whether they "work".

I see that there will be significant issues in modelling the "secret"
components of the CW unless someone has worked out an RF equivalent
circuit of those components (the isolator and matching unit).

Thanks...

Owen

Owen, I have done some tentative modelling of the CW; how valid the model
is, I am not sure. I used the "TL" card for the actual coaxial feedline,
and ran a single wire from the antenna feed point to one side of the TL
source segment. The idea was to replicate the coaxial surface current. I
don't think the balun (Isolator) will have any effect on the antenna
performance. I may even have the code saved someplace if anybody is
interested. Why would you not use a calibrated EMC monopole for HF?

Frank