Hello 222 addicts,
I had both 222 yagis ready to go up the tower on Thursday. The weather
was gorgeous with little wind, but I could see that it was a two man job
at least for me who is 78 and 2/3rds years old. The antennas are heavy
with thick aluminum support struts so man handling them around at 106 ft
is no picnic. So I spent Thursday tweaking one of the antennas to align
the phase center a bit better and make the boom sit parallel to the
horizon. In the past the top yagi that recently broke had a noticeable
up tilt. It had to be fixed by cutting and re drilling the support
braces. So I got it all lined up on the ground and on Friday, I
convinced Al WA1T to help me haul them up. All went well. We were on the
tower for four hours. I got both yagis back in place, then they had to
be aligned and the vertical mast on one side of the H frame along with
two long yagis was lifted up several feet to its final position. When
that was accomplished, I had to drag the H frame sideways on the main
mast to get it centered again. That frame is very heavy with the four
yagis plus the H frame. I used ratchet straps to move the frame. Then I
had to re connect all the coax and tighten seemingly a million half inch
hex nuts to lock the frame in position. This morning I was up on the
hill getting firewood in my truck, and went in the shack and turned on
the solar power and listened on 222. Wow conditions were bad. Lots of
gusty winds. I turned the 222 antenna back and forth while listening to
a beacon, and happily found only one main lobe. I worry that with
everything else going on that I might get the antennas mixed up and put
something out of phase! (all four T matches have to be oriented
similarly) So I listened to K2DLL and it was real watery sounding but
was much stronger on the 4X yagsi vs the 8 X 5 el LVA. The LVA is aimed
about 33 degrees off of K2DLL, so gain is probably down by 5 dB. 26
degrees off boresight is the 3 dB point on the LVA with a 52 degree half
power point. Then I tried listening to W3CCX/b and was really amazed by
what I saw. W3CCX was weak at about 10-15 db above the background noise
on the big array, and when I switched to the LVA I could not hear it
much at all. There was at least 8 dB difference between the two. Now
you get weird conditions and QSB where antennas at different heights get
favored etc, but 8 dB is a huge number. We figured the LVA is 18 dBd. My
best guess is that the 4X array is around 22-23 dB. My take is that the
array is back to working again.
In honor of fixing the array, I plan to offer an award to the station
farthest away that can work the 4 yagi array on Tuesday night. In the
past there was a Bass Pro Shop bass boat and trailer being offered for
the longest QSO. This time, in honor of WA1T helping out, the prize
will be Al's pick up truck. He doesn't know that yet, so lets keep the
award between ourselves for the time being.
So it looks like Tuesday night will be the on the air test for the
repairs. Maybe I can test it out before 7 PM so I can be all set to go
then. I can bring up an antenna tester and look it over before the
activity begins. In looking over the damaged antenna, I would say that
nothing hit the array other than wind. I found a 432 yagi that had also
been twisted on the mast, so I am guessing that the culprit for all the
damage was some wind from a dust devil. If you want to know about dust
devils check this out: https://en.wikipedia.org/wiki/Dust_devil
If you read the fine print in the article about dust devils you will
find that the first recorded instance of a fatality occurred here in the
town of Lebanon, ME. My UPS driver at the time in May of 2003 saw it all
happen. The dust devil ripped apart a building and launched 4 x 8 ft
sheets of roofing metal skyward up and out of sight. For many minutes
afterward, those sheets of metal were falling all over town! He was
rather traumatized by what happened. The day was warm with absolutely no
winds and 100% sunshine. I suspect the ridge top where the antennas are
is solid rock and the rock got very warm triggering the dust devil. I
am relieved that I got it all fixed.
73
Dave K1WHS
Remember Tuesday is 222 Night. SSB/CW/FT8/ Q65/ Facsimile/ Show up on
222.100 or so and see what happens!!
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