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[Towertalk] 160m Inverted L

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Subject: [Towertalk] 160m Inverted L
From: (Kevan Nason)
Date: Sat, 10 Aug 2002 20:17:23 -0000
After a couple years of 'listening' I've finally joined.
Thank you all for your help -- even if you didn't know you
were giving it.  I'm still learning some of the basics
and thought y'all might help out again.  I'm new to using
an antenna analyzer.  Used to simply use the SWR bridge.

I'm constructing an inverted L for 160m and am unsure of how
to proceed.  My MFJ269 tells me the following:
Freq    Rad. Resis     XL     SWR
1.9         45         155    13.5
1.7         32         28     2.3

I haven't measured my ground characteristics, but judging by
the general documentation available for this area and the 
large amount of clay around I figure its poor.

My question is this.  If antenna efficiency is:

        eff = Rrad/(Rrad+Rloss)

and I don't change Rloss by running more radials or some 
such (I ran out of wire and want to play in the NAQP next 
weekend); would I be better off leaving the length as is and 
cancel the inductive reactance with a capacitor, or should I
keep on trimming the antenna.  If keep trimming, how far?
Until Xl is zero and then match the antenna using
a transformer or antenna tuner?


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