Sunday 14 July 2013

IARU HF World Championships

The last week has been a bit of a blur around here.  I have been attempting to get a LDG S31 vertical antenna in the air ready for the IARU contest.  The main reason for this is that my 80m OCF dipole does not allow me to tune on 15m, even with a manual tuner, and as a lot of the DX action happens on that band.... I needed to be able to operate there to get a good score.

Apparently the Gods were totally against me.  The S31 went up in the air, the radials were laid out, 4:1 balun hooked up, a brand new 100' of RG-213 was connected, and.......the antenna tuned every band but 15m...... !!  Now, it's not like I haven't put up a 31' vertical antenna before, in fact I use a homebrewed version of the S31 when I operate portable, and it works great.

The other interesting fact is when comparing signals between the vertical and the dipole, there was a huge difference.  An S9+20 signal on 40m using the dipole was a measly S1 on the vertical....and it was that way over every band when I compared the antennas to each other.

So, over the course of three days I changed every part of the antenna, the coax, and added many more radials.  Nothing changed, it was a crap antenna.  Several emails went to Bob, VA3QV, who has this type of vertical looking for advice, but Bob couldn't understand what was going on either.

In the end I used my 66' long wire, 9:1 Balun, and two 31' radials and worked a good portion of the world with it.

Band conditions were not that good, we had very deep QSB for most of Saturday afternoon which made things difficult.  My first five contacts were Iceland, Russia, Hawaii, Greenland, and Moldova....after that the DX disappeared and only US stations were heard until very late afternoon.

It was a lot of fun but a tough slog, but in the end I put 122 contacts in the log, including a new one for me, TC3HQ in Turkey.

Oh yeah, the S31 vertical.......apparently the issue was a broken, but brand new, right out of the box, MFJ RF Isolator that I had put in line......I've removed it from the run of coax and ....the antenna works fine now, as advertised, because the contest is over !!

1 comment:

  1. It's funny how things just don't seem to go right at times. I have had problems with software during a contest that have never happened at any other time....but during the contest that's when things can go wrong. To bad things got working once the contest was over...but....at least you found the problem. As I was told a long time ago "just because it's brand new does not mean it works" I have had the same issue with new items it being the last thing I checked as it was new and supposed to be working correctly. I sure have spent a lot of time trying to solve an issue and it turned out the new item I never checked seemed to be the trouble.
    Mike

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