Those readings are just about what you would expect from an L of your
dimensions with a less than perfect ground system. Your feedpoint impedance
is probably a little higher than 50-ohms right now. With a really good
ground system the feedpoint impedance should fall a bit, down closer to
35-ohms or so. There is actually no need to do any matching for an Inverted
L fed with 50-ohm coax unless it is way too long or short as long as you can
tolerate an SWR of less than 2-to-1. One way to "tune" an L is to put in
the best ground system you can in your location, use a vertical run of 60 to
70 ft, and then adjust the horizontal length for the best match.
-----Original Message-----
From: towertalk-admin@contesting.com
[mailto:towertalk-admin@contesting.com]On Behalf Of FireBrick
Sent: Tuesday, August 20, 2002 10:29 AM
To: TowerTalk List
Subject: [Towertalk] Inverted L update
Subsequent to my previous post. I just for grins hooked a piece of coax to
the inverted L with the braid going to the ground that all (don't laugh, 4
radials) is attached to.
I'm seeing
1801 1.2 to 1
1902 1.2 to 1
1950 1.35 to 1
1997 1.5 to 1
This is too good to be true.
So why the good readings?
BTW: no match at all on 80
And I forgot to say that I had a Sommer 15 foot boom multiband on top of the
tower.
-----------------------------------------------------
Anything worth fighting for is worth fighting dirty for.
-----------------------------------------------------
Bill H. in Chicagoland
w9ol@billnjudy.com
www.billnjudy.com
http://files.billnjudy.com
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