Date: Sat, 4 Feb 2017 05:19:55 +0000 (UTC)
From: Bob K6UJ <k6uj@pacbell.net>
To: <towertalk@contesting.com>
Subject: [TowerTalk] Force 12 EF420 manual
Anyone have a manual for a Force 12 EF420 or a EF420/240 ?I am interested in
the taper schedule used in a EF420.? I am thinking of making
one from my collection antenna parts from Force 12 yagis I have had.
BobK6UJ
## Is this for the 37 ft eles..or the 44 ft eles. If its the 44 ft eles,
I have 2 of em, sitting on saw horses right now in the back yard.
The 44 ft ones start off with 1.25 inch OD, but are triple wall, then it
tapers down a bit, and is double wall, then the insulator, then
from insulator to tip its all single wall. Each ele weighs aprx 12 lbs. I
have run it through the dx eng mech software and its very robust.
## the triple wall inner portions consist of .083 wall, then some .058 wall
insider that, then some .035 wall inside that. Then they swedged the
entire mess down, to fit the .750 fiberglass center insulator.
If you want exact exposed lengths, diameters and wall thickness of each
section, and overlaps, etc, etc, contact me off list. Both the 37 ft and 44
ft
40m eles used LL wires, alumo weld. These cam easily be replaced with coils
across the oem or slightly longer insulators that are aprx half way out
each ele half. T bars would also work, and would be very short on the 44 ft
eles.
Jim VE7RF
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