Aloha Ian, you wrote, in part:
> Hi om,
> today I have mounted my new Force 12 C4 on the tower.
> The tower is 40 feet high from the roof, that is about another 40 feet
from
> the ground.
My C4 is about 60 feet above the ground. Here are my
measurements of vswr, here in the shack at the end of
my two coax runs:
40 Meter Dipole element:
7000......1.2:1
7032......1.5:1
and it goes on higheer to 7300 where swr is 7.9:1 !!
I use an antenna tuner, of course. I probably did not
space/set the hairpin matching coil correctly at the
feed point. Also, I use an F12 B-1 balun.
20 Meters
14005.....1.3:1
14050.....1.2:1
14100.....1.1:1
14195.....1.2:1
14300.....1.4:1
15 Meters
21100.....1.1:1
21200.....1.3:1
21300.....2.0:1
10 Meters
28010......2.4:1
28300......1.3:1
28400......1.1:1
28500......1.0:1
29000......1.3:1 (where I can work AM stations)
29470...... reaches 2.0:1
The holes I selected for the rivets were always
the center holes, so that got me well above the CW area
on 10 meters, but again, can use a tuner for that area.
Are you sure you used 50 ohm coax ? Did you use an
F12 B-1 balun at both antenna feed points, I did, don't
know if that would make a difference. Most probable
cause I can think of would be the wrong coax type,
but that is an unlikely error, hi.
Anyhow, that is my info, Ian. SWRs check out with
both my MFJ-259B analyzer and the meter on my
FT-1000.
73, Jim, KH7M
On the Garden Island of Kauai
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