What follows is long, wordy!!
Guess they win. The V-beams will not be up for
the CQWW. Am sun burned, and just don't have
the energy to scramble enough to get all the
wires "just so", or even any other way for this
weekend.
Follows is a plea for advice, maybe encouragement,
or just perhaps a recommendation to abandon the
project!
Do the legs of V-beams have to be exactly equal
in length?? I know they should, but as the
terrain beneath each leg is so unequal, and
the far ends will not be at equal elevations,
will several dozens of feet in length difference,
out of several hundred feet matter too much.
Present situation re leg length:
Leg No. 1 running toward 130 az is 600 ft long.
Leg No. 2 running toward 180 az is about 500 feet long;
possibility with some considerable added effort
could get it longer, but would be deep into woods.
Leg No. 3 running toward 220 az is out 565 feet or so.
Leg No. 4 runs toward 260 az and out only about 484 feet,
and to get further, it would dive down deeper into the
ravine valley to reach the next available tree tie-off point!
Lines 2 and 3 span the ravine valley, filled with hau and vines.
Lines 1 and 4 are strung roughly along the ravine near side;
these lines are just above the tops of many trees growing
up from the near side slope of the ravine below, very tough
working these lines into position!!
These lines, 1 and 4, form the obtuse 150 degree angle V which ought
to have the main radiating axis aimed about toward 105 deg
for the beam mouth(toward South America from Kauai) and SE
down the length of the Hawaiian island chain from here, and
the apex aimed toward Asia at 285 az; JA, BV, HS, VU nearly
on axis of anticipated beam formed.
Beam formed by legs 1 and 2 will have the open end of the
V, the mouth, toward 155 az, or the long path to the
Mid East from here, direct to the South Shetlands short
path; and the apex is aimed over Kamchatka peninsula across
Siberia and on toward the Black Sea.
Beam formed by legs 2 and 3, open end toward West Africa
long path, and short path from the apex toward N. Canada,
Greenland, W. Eu, Spain and on into Africa.
Beam formed by legs 3 and 4, open end toward 240 az, VK land,
apex to the US mainland at 60 az.
Note that the "mouths" of the V's all are directed into the
Southern hemisphere, only way I can get them strung; but
the long path is great from here, as it is over open ocean
all the way down and back up the other side to just about
anywhere, except Africa is on the way toward Eu, which
is directly over the pole from KH6 land. Beams from
the V's of legs 1-2 and 2-3 would go that way short path
with the gain down 2 or so dB from the long path direction,
as these will be non-terminated V's, so will be
bi-directional except for the slightly lower gain in
the apex directional.
Of course, all the above dandy planet coverage only would
happen, theoretically, with the V's high, over flat earth,
and with equal length legs!! I have tried modeling the V's
using Brian, K6STI's AO program. It seems to show that
unequal leg lengths is not a big deal; still seem to get
lots of gain. I would think that with unequal leg lengths,
the currents in the transmission line would not be equal,
and therefore, not balanced, so will get feedline radiation
to boot, true? Not sure if AO takes that into account and
may be why the unequal lengths seems to not harm the performance
so much. Perhaps the balance is lost anyway with all the
other unequal parameters, other than length alone, which
are characteristic of this installation site.
Anyway, I am nearly pooped out fighting this project which
began back in June!! I really believed I would have this
finished by this weekend; but not.
Maybe I'll feel better about this when I go for a swim,
shower and have an 807 or two!!
73 and Aloha,
Jim, KH7M
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