On Tue, 21 Jun 2005 11:37:57 -0400, "Walter Maxwell"
wrote:

[snip]

Walt,

Your's was a particularly heroic effort and I commend you for it.

I have taken the data you supplied in text form, converted it to comma
separated values (csv) and imported it into XLZIZL where I can use
your measured input values, add the two different transmission lines
that you used and compute the load resistance at the antenna.

I know that you supplied these results, but I find slightly different
answers and I believe the reason is as follows:

I'm guessing that you calibrated your two lines as one. If I'm wrong,
slap me upside the head.

Depending on the exact type, RG58(x) has slightly different Zo values.
RG141 is specified as 50.0. Your Zo of 54 and your phase constant
suggest a Vp of slightly less than .66, which is remarkably close to
specification, but slightly low, considering the ~5% (2', RG141) of
your composite line has Vp ~ 0.7.

This is really getting fussy, but I'm beginning to believe that to
possibly make a determination about ground characteristics based on
antenna Z measurements, the measurements are going to have to be very
precise.