On Mon, 20 Mar 2006 17:54:19 -0500, Dave wrote:

Owen Duffy wrote:

On Mon, 20 Mar 2006 21:31:02 GMT, Bob Miller
wrote:



Second, you should measure the antenna feed point impedance at the
feedpoint, or 1/2 wavelength from the feed point [coax corrected for
velocity factor].


Why the half wavelength?



A 1/2 wavelength transmission line repeats the load impedance at the
antenna with minimum loss, assuming you cannot get an analyzer at the
antenna itself.

IMO, measuring directly at the antenna and solving the matching/load
problem there is the easiest and best method. You are free to disagree.

Ok, but again you can measure the impedance anywhere and knowing line
parameters, calculate Z at any other point.

Owen
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