Topband: buried radial problems.

[Enzo]

  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.