Correct; was a typo.
I meant the shack impedance or impedance seen by the matchbox.
Sorry, I'm on vacation with a tiny little tablet, typing in a hurry before
my XYL yells for me to QRT.
And the impedance at the shack end is exactly what I wrote.
Rick
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim Brown
Sent: Monday, July 18, 2016 9:50 AM
To: tentec@contesting.com
Subject: Re: [TenTec] OT: Question to the group
On Mon,7/18/2016 12:25 AM, rick@dj0ip.de wrote:
> The feedpoint impedance is not only dependant on the impedance of the
antenna but also on the transformation of impedance due to the specific
length of feedline . . . which varies from one band to another.
NO! The feedpoint impedance is AT THE FEEDPOINT -- that is, up in the air
where we connect the feedline! And THAT is determined by the antenna, it's
surroundings (soil, mounting height, other objects) AND the common mode
effects of the feedline. But NOT the transformation of the Z by the line --
THAT'S the Z that the tramsitter sees, and that would be measured by a good
measurement device at the TX end of the coax.
73, Jim K9YC
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