I was going to repost everyones' posts, but almost everyone gave me
basically the same thing. Notably absent were real-world comparison
reports like the kl7(forget the sfx-sri) summary here recently. I
really liked that one.
Anyway, Most pointed out the following items:
1./ Helium is fairly heavy to carry, and may not be permitted aboard
certain airplanes.
(keeping in mind, that I was researching this for a possible
mini-expedition next summer to cy9, fp, vo2, or vo1)
2./ Balloons vary. The cheaper ones are good for about a day barring
adverse WX condx. The good ones can stay up 2-3 days (or more)
given ideal WX condx. Some mentioned the balloons popping when they
were exposed to long periods of hot sun. (Noontime 160m dx?-hi)
Again, possibly the more expensive ones wouldn't be as subject to
UV radiation, or expansion/contraction stresses.
3./ They will take your antennas as high as need be. One fellow stated
he flew his up to 700' (albeit accidentally)
(I would worry about low flying aircraft. On our trip to Sable, we
were as low as 500' at times due to heavy cloud cover in areas. I am
probably overstating the obvious, however. . . )
4./All stated good results, again given ideal WX...None stated that
the balloon was 5 s-units better than their BRAND-X
1/4wave SuperDuper model II sloper
at 90' or anything to that effect. Reports tended to be vague, again
unlike the recent kl7 report. No0y uses a balloon with good results
on a semi-regular basis and JON always puts in a good signal here in
NB
5./ Most said that even a fair breeze would tilt the ballon over or
even take it right down. They reminded me that coax and a tag line
can be heavy if long enough. Also stated was the fact that when the
antennas tipped, SWR soared, and radiation pattern went out the
window. In otherwords-- UP!
6./ Safety was the concern of many, no doubt due to experience
with trees and power lines. No power lines on Sable or St.Paul Isl.
Thank Goodness.-hi!
7./ None reported matching problems. I ASSUMMED that everyone was
feeding it against raised radials so as to get close to a direct
50ohm feed with a direct coaxial cable connection. Configured as a raised
ground plane with the radials at 45deg. or so I would geuss.
8./ Two mentioned static buildup, but no real particulars as to how
to illeviate the problem. A resistor at the rig one said, but not
what wattage/resistance, or exactly how it is placed in the circuit.
A good idea nonetheless. Ground antenna when not in use.
************summary***************
All in all expect a balloon to outperform lesser/lower
antennas. How much- I don't know. If TopBand is a top priority it
may be worth the extra baggage, but I would still pack a BattleCreek
Special (or simliar) as the number#1 antenna, with the balloon as a backup or
alternative antenna. If it was only a 1-man Expedition, I think the
balloon would be the way to go, _IF_ you are willing to risk it
coming down. (hint+take 2 or more balloons)
Maybe we should hear a bit of comparisons from guys like km1h,
w3lpl, and the like, who have verticals and ground planes at pretty
good heights, just to "imitate" the balloon supported ground plane
as opposed to a low inverted L (the regular choice of 160m
dxpeditions) Anyone give us any "A vs. B" reports? Carl?
Perhaps someone could comment on their use of the OH1RY and/or
the AKI special, and even the Battlecreek Special to compliment my
short and uncomplete report on "DX-pedition antennas for Topband"
where the QTH doesn't include any Palm trees or 20 story Marriott
Hotels like on Sable, St.Paul, or St. Pierre & Miquelon. (as well as
90% of the other really rare spots that dxpeditioners go.)
All from here for now. I apologize if I have overlooked anyones'
"balloon" comments to me. I just got in from snowblowing the driveway
and the sweet sounds of the Sable sand and surf seem a century away.
But I digress. Hope you had some fun reading this report.
Cu on Top!
MIKE
Michael & Coreen Smith (AA Antennas & Wynder Photography)
271 Smith Rd, Waterville,
Sunbury Co.,NB, Canada
E2V 3V6
Ham call=ve9aa / ve9ms/b (ex-cy0aa,ve1mq,ve1btt)
6M Vhf buffs;
See the *NEW* AA Antenna web page at:
http://members.tripod.com/~ve9aa/index.html
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