On Wed, 6 Jul 2005 23:05:03 -0400, "Walter Maxwell"
wrote:



I have just added a function (DLoss) to calculate loss as per your
appendix to the graphic at http://www.vk1od.net/temp/LineLoss.htm ,
and it can be seen that in this (perhaps extreme) case, it is not a
very good approximation.

I also added the same calcs for f=100MHz and Zo is much closer to
real, and it can be seen the approximation is much closer.

Owen

I'll have to study your math, Owen, to let it sink in. I don't get it on the
first glance.


Sorry all,

The function for DLoss on the web page was for the additional loss due
to SWR. I have now added a term to the DLoss function to include the
matched line loss and updated the web page.

The outcome hasn't changed in that the two methods of calculating loss
only agree if Zo is real.

Owen
--