I installed a Titanex V160HD along with its own matching unit V160A. I'm
puzzled about what is going on with the radial system I'm testing:
1.. 60 different length radials centered on antenna base. They're made of
insulated copper 1.5 mmq in section.
2.. 35 different length radials centered 25 m away from the antenna. They are
a part of a previous vertical antenna I installed some years ago, too short for
160m.
3.. 2 elevated radials for 160m.
If I connect the system #1, as I thought to do at first, I CAN'T tune the
antenna! So I made different measures with the systems. For my tests I used a
MFJ 259B.
On 1.83 MHz shows as follow:
a.. System #1: R=0, X=58 SWR=9;
b.. System #3: R=34, X=34, SWR=1,8;
c.. System #2+#3: same as #3;
d.. System #1+#2+#3:R=0, X=80, SWR>25.
Than on 3.65 MHz:
a.. System #1: R=20, X=40 SWR=2.3;
b.. System #2: R=48, X=9, SWR=1,2;
Finally on 7 MHz:
a.. System #1: R=15, X=53 SWR=6.1;
b.. System #2: R=50, X=1, SWR=1.
After a couple of months since I buried the centered radial system, 60% of them
have the copper darker that seems to be oxidized.
I also measured the voltage between radials and the antenna: 76 mV ! It's
probably due to an AM BC station on 1.45 MHz close to my QTH, 2 Km. They switch
off it during the night, but while it's on, both analogical and digital display
of MFJ-259B still moving swift.
Is there anyone can explain what's happening with the first radial system?
73 de ik3swb.
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