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[TowerTalk] Shunt Feed

To: <>
Subject: [TowerTalk] Shunt Feed
From: (Tom Rauch)
Date: Fri, 28 Sep 2001 20:44:29 -0400
> capacitance to the series cap in the shunt feed and measured the Z, I
> could see it come down as I added more C -- in other words, it behaved
> as I expected.  I found that with 440 pf in series, my Autek RF-1 says
> that minimum Z occurs at 47 ohms at 1895 khz.  It is a relatively
> sharp minimum.  

Z is not R. Only R=50 j=0 is a 1:1 SWR referenced to 50 ohms. 
Z=50 can be an infinite SWR, or perfect, or anything in between. 
> Yet when I switch the meter to SWR, it says it is off-scale high. Is
> this possible?  Doesn't minimum Z (R+j0)represent resonance?  And if

Not in a high Q system that is changing resistance rapidly with 

What is R and X?

73, Tom W8JI 

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