Pete-
I've had good luck with the longer approach. I put a 30-150pF variable cap in
series with the feed point and nulled the SWR at 1830 KHz. I have only two
elevated radials (each 135') but it tunes and loads fine with 500 watts. The
longer top sloping wire adds the inductance you would otherwise need to provide
with an inductor at the feed point.
With the longer total length and series capacitor my RigExpert AA-54 shows 50
ohms resistive load and 0 ohms reactance at resonance.
73,
Steve
N6SJ
-----Original Message-----
From: TowerTalk <towertalk-bounces@contesting.com> On Behalf Of N4ZR
Sent: Friday, October 5, 2018 8:12 AM
To: TowerTalk <TowerTalk@contesting.com>
Subject: [TowerTalk] Length of Inverted-L.
What to do when two respected references differ? ON4UN's book assumes an
Inverted-L is always a quarter wave ~135 feet), while the ARRL Antenna Book
assumes 165-170 feet. ON4UN mentions longer antennas to increase feedpoint
impedance, but doesn't seem to put much faith in that.
Comments?
--
73, Pete N4ZR
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at <http://reversebeacon.net>, now
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