CQWW 160-Meter Contest, CW
Call: WA7BNM
Class: Single Op, Low Power
Location: S.Calif
Q C S
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153 4 42 = 16,468
First time ever in this contest. Also first time ever that I've had an
antenna that was designed to be resonant on 160-meters. In the past I've used
my 40-meter antenna and just pushed the "Tune" button on the transceiver
autotuner until it matches whatever its seeing (coax, 40m antenna, switchbox,
etc). Usually takes about 10 seconds to find a match, and if I move more than
2 kHz, I have to do it all over again. This method worked well enough to produce
a couple of mults in a contest.
Inspired by AB6FO's posting about using a balloon suspended 160m antenna
during NAQP CW, I spent Thursday evening looking through the literature and
calculating wire lengths for a vertical and radials. Contest proceeded as
follows:
Time
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2200Z 1400PST Contest starts. I'm at work debating whether I can actually
get a balloon antenna up for the contest.
2300Z 1500PST Decide to "run an errand" to local electronics parts store
to find some small gauge (light) antenna wire. Helpful
salesman has none but tries to get me to buy computer cable
that I can "pull one of the conductors out and use."
2330Z 1530PST On way back to office from electronics parts store, I
drive by Home Depot. Hey, maybe they have antenna wire. Quick
check of electrical department, and I find 500 ft of
18 gauge bare stranded copper wire. This is the first
omen that I'm meant to put an antenna up.
2345Z 1545PST Continue to party balloon outlet near office and buy ten
36 inch diameter latex balloons (the largest they have)
and rent a cylinder of helium. During morning's phone
coversations with balloon suppliers, I had learned that
1 cubic foot of helium will lift 1 ounce. Zowie, that's
not much.
0100Z 1700PST Explain to my office colleagues why I need to use a balloon
to suspend an antenna when I already have what they perceive
as a huge tower and antennas.
0115Z 1715PST Finally leave the office when I realize that I have no
extra coax and need to buy 100 feet at the local HRO. While
daydreaming about big signals from balloon antennas, I miss
exit on freeway for quickest way to HRO (brain was on auto
pilot for home). Unfortunately, I don't realize I've missed
the exit until I've passed two more exits. Backtrack and
get to HRO one minute before closing (glad our watches were
synchronized). Buy 100 feet of coax with connectors.
0145Z 1745PST Arrive home and start measuring out radials in driveway,
using 500 feet of 14 gauge stranded, insulated electrical
wire previously purchased. Makes three radials and one "short"
radial. Cut 18 ga bare stranded copper to resonate at
1850 kHz. Load plastic bucket with dirt as an anchor for
balloon. Place bucket in front yard of my 50 ft by 130 ft
residential lot and start stringing radials.
0230Z 1830PST My wife arrives home and inquires what I'm doing. I reminder
her of our discussion about the importance of balloon
antennas and that her primary question had been what color
would the balloon be. She says she didn't realize I had
planned on using the front yard as the launching area.
0330Z 1930PST Manage to keep two radials completely on my property by
bending them around house and running along edges of lot.
I run the third long radial across front lawn (for you
guys with big lots, my front lawn is roughly 15 feet by
30 feet) to street curb. Run remaining wire along curb past
two neighbors' houses. Short radial goes along curb past
neighbor on the other side.
0400Z 2000PST Go out to dinner to a restaurant with my wife.
0500Z 2100PST Start inflating balloons in the garage. Earlier "calcu-
lations" indicated that it would require two 36 inch balloons
to lift antenna wire, insulator, etc. Decide I don't want
to push my luck beyond about a 32 inch diameter. Second
balloon explodes in the garage.
0530Z 2130PST Launch two-balloon antenna. Supports everything just fine.
While connecting radials to coax connector, one balloon
explodes. Antenna returns to earth.
0545Z 2145PST Decide to use three balloons in order to have a margin of
safety. If I lose one balloon, I'll still have enough to
keep the antenna up. Start wondering if I'll only end up
with 15 minutes of operating time while the antenna stays
up.
0555Z 2155PST Launch three balloon antenna and finish connecting radials.
Learn that no wind on the ground does not necessarily mean
there is no wind at 125 feet. Watch antenna wire drift toward
70-foot trees between sidewalk and street.
0559Z 2159PST Run to shack to see how antenna works before there are more
problems. Antenna appears to have 1:1 SWR at 1800 kHZ, rising
to 3:1 above 1915 kHz or so. Geez, I can actually work people.
Work S&P and find I can work most stations I can hear, while
running low power, including PJ9 and VP9. Before calling it
quits for the evening, decide to try CQing. Spend the next
1.5 hours working U.S. and Canada at modest rates.
0945Z 0145PST Try to lower antenna, but find it hung up in trees. Remove
radials from neighbors' curbs and go to bed.
1415Z 0615PST Get out of bed and manage to extracate antenna wire from trees.
Lower antenna and store balloons in garage before neighbors are
up.
After moving the antenna launch point further back from trees on Saturday after-
noon, I managed to get on from 0200Z until 0316Z, when rain and wind grounded
balloons. Not sure I'm going to work much DX with a balloon antenna, while
running low power and having no special 160m receiving antennas, but had a good
time.
73 de Bruce, WA7BNM (bhorn@netcom.com)
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