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[TowerTalk] analyzing antenna systems - some questions

To: towertalk@contesting.com
Subject: [TowerTalk] analyzing antenna systems - some questions
From: k7wxw <k7wxw@arrl.net>
Date: Mon, 20 Mar 2017 10:32:50 -0700
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
I am building my own antennas and have a couple of questions about using 
antenna analyzers properly. Here's the setup:

I have a 133' doublet, fed with  46' of 450 ohm window line, into a Johnson 
matchbox.  My rig is a FT-897D. I mostly run QRP though I venture up to 100W on 
SSB.  Because my inline SWR meter is on the repair bench, I depend upon the 
rig's SWR indicator. 

To characterize the antenna/tuner system from the radio, I've connected a Comet 
CAA-500 on the radio side of the matchbox to sweep through the bands by hand. 
Basically I set the frequency on the analyzer, and tune for lowest SWR.  So 
each measurement consists of the bandswitch/tune/match settings on the matchbox 
and the SWR and ohmic readings on the analyzer. 

So, three questions: does an analyzer like the CAA-500 have enough drive to 
properly drive the matchbox/feedline/antenna system?  If it doesn't, what other 
options do I have for characterizing the antenna system?  

And lastly, can anyone point me to a good tutorial on Smith charts? I'd like to 
see if I can convert the impedance I am seeing at the matchbox to what is 
happening up at the dipole feedpoint. 

Thanks and 73 de Bill K7WXW
_____________
wag more, bark less.
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