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Peter Laws <[log in to unmask]>
Tue, 26 Feb 2008 11:00:21 -0600
text/plain (8 kB) , plaws.vcf (8 kB)
 From VP6DX via ARRL.  Note that they have WiFi on the atoll.

Ducie Island, VP6DX: Making Contacts, Breaking Records

After 13 days, 7 hours and 37 minutes of continuous operation, the VP6DX
Team on Ducie Island, made their 168,723rd contact. Valeri Koursov, RA0ALM,
of Krasnoyarsk, Russia, contacted the Ducie Island expedition on Monday,
February 25, 2008 at 0437 UTC on 30 meters. According to documents
maintained by Jari Jussila, OH2BU, this contact breaks the record for the
largest number of contacts made by any radio expedition. The previous
record was held since February 8-28, 2001 by the Five Star DX Association's
DXpedition to the Comoros Island, D68C.

A few moments after VP6DX's record-breaking contact, the pre-moonrise
starry skies above Ducie Island sparkled with a barrage of flares launched
from the deck of the M/V Braveheart in celebration. The 13 operators and
six-member Braveheart crew congratulated each other with handshakes, hugs
and some strong coffee. But deep pileups of European and North American
stations were still calling, and soon the seven on-duty operators were back
in front of the radios, while the others crept off to their cots to catch
up on sleep in the cool of the evening.

The Ducie Island DXpedition has broken other expedition records in recent
days, including:

 The largest number of RTTY contacts, previously held by the Swains Island
N8S DXpedition in April 2007.

 The largest number of SSB (voice) contacts, previously held by the
Comoros Island D68C DXpedition.

 The largest number of contacts on 40 meters, previously held by the Libya
5A7A DXpedition in November 2006.

 The largest number of contacts on 30 meters, previously held by the St
Brandon Island 3B7C DXpedition in September 2007.

 The largest number of contacts on 17 meters, previously held by the
Swains Island N8S DXpedition.

 The largest number of contacts with North America, previously held by the
Comoros Island D68C DXpedition.

 The largest number of contacts with South America, previously held by the
Peter I Island 3Y0X DXpedition in February 2006.

 The largest number of contacts with Africa, previously held by the
Rodrigues Island 3B9C DXpedition in March-April 2004.

Long Path Contacts on 160 Meters with Ducie Island

Earlier, the VP6DX Team reported that a contact on 160 meters had been made
with Chris Dabrowski, A45XR, in Oman -- the opposite side of the planet
from Ducie Island -- on February 18, near Ducie Island sunrise. All of the
stations contacted in Europe were in their late afternoon, with the sunset
terminator approaching.

Three days later, a series of long path 160 meter contacts were made
between Ducie Island and stations in Ukraine and in southern European
Russia; the VP6DX Team worked 11 stations from 1345-1430 UTC. Signals were
best on the 225 (Ukraine) or 195 degree (Russia) Beverages and inaudible in
other directions, confirming a long path route with very little or no skew.

Contacts with southern European Russia used a path from Ducie Island
south-southwest over Antarctica, then north across the southern Indian
Ocean (Heard Island, Mauritius), across the Persian Gulf and Iran into
Russia. These paths are 23,000-24,000 kilometers long.

For the Ukraine, signals followed a south Pacific Ocean path into the
Southern Ocean below New Zealand and Australia, then near the Maldives, the
Persian Gulf and finally toward the Ukraine.

During the same time period, a station in the Moscow City oblast was also
contacted. This signal clearly arrived on the short path, crossing over
Scandinavia. Signals were loud on the 15 degree Beverage antenna and were
barely audible on the 195 degree antenna.

Scandinavian and Northwest Russian stations looking for a 160 meter contact
with Ducie Island should check this time for a short path opening. Stations
in Ukraine and Southwest Russia should look for the long path.

During the hours leading up to and including this long/short path opening
to Europe, Oman, Mongolia and Tajik stations were also contacted on their
short path directions.

The VP6DX Team looked for the same opening the following morning, but
without success. They report that the 160 meter operator team will keep
checking through the final day of operations. Departure from Ducie Island,
now scheduled for Thursday, February 28 at 2000 UTC, has been delayed by
1-2 hours so that a final attempt can be made to work more Eastern and
Northern European stations during this unique opening.

Description of Stations on VP6DX

The Ducie Island crew has received inquiries about the equipment and
antennas used on Ducie Island. They report that each operating position uses:

 Elecraft K3 radio. They say "The outstanding receiver and transmitter
characteristics allow us to run two positions simultaneously on any band --
even the very narrow 30 meter band -- with absolutely no interference. Good
design makes the complex appear simple: the ins and outs of this
sophisticated radio were quickly mastered by the operator team, none of
whom had seen a K3 before the expedition."

 Microham microKeyer II computer interfaces: plug in, turn on, call CQ and
get to work.

 Acom 2000, 1000 or 1010 amplifiers: quietly getting the job done without
trouble. The position used on 160 meter includes an OM 2500 HF amplifier.

 200 W W3NQN bandpass filters from Array Solutions and 2 kW bandpass
filters from 4O3A.

 WinTest logging software running on Durabook ruggedized laptops.

 Honda EM65is and EM30is inverter supply, gasoline generators. The
operators report that the generators offer "100 percent reliability to
date. The inverter system has been very tolerant of the widely varying
loads presented to the generators as multiple operating positions switch
between transmit (high power consumption) and receive (low power
consumption), a vast improvement over previous gasoline generator designs."

The seven operating positions are divided into two sites: East (four
positions) and West (three positions). The operating sites stand about 1
kilometer apart, a 15 minute walk over a coral shelf bordering the island's
inner lagoon. Each site has its own WiFi network; a microwave link ties the
two sites together. Sleeping tents and meals are located at the East camp.

The antennas include:

 160 meters: Titanex vertical (West)

 80 meters/30 meters CW: Titanex vertical (West)

 75 meters SSB: SpiderBeam 4-square (East)

 40 meters: two SpiderBeam 4-squares (one at each site)

 30 meters: Spiderbeam 4-square (East)

 20-10 meters: two Spiderbeam 2-element vertical Yagi arrays on each band,
one located at each site.

 6 meters: 5-element Yagi

An array of Beverage receiving antennas sits midway between the two sites.
Each Beverage is constructed using DX Engineering two-wire Beverage kits,
providing two directions for each installed antenna. At present, four
Beverages (eight directions) are in available to the 160 meters, 80 meters
CW and 75 meters operator.

Each operator has independent choice of his receiving antenna. The receive
antenna distribution system includes DX Engineering pre-amps, packaged with
custom filter, switching, and protection hardware designed and built by
Eric Scace, K3NA, and George Cutsogeorge, W2VJN. On-site construction was
done under the hot sun by Robin Critchell, WA6CDR, and Milt Jensen, N5IA.

Receive antenna directions available to the operators are:

 015 -- Western USA, Eastern Europe short path (about 200 meters in length)

 045 -- Eastern USA, Western Europe (two parallel 200 meter Beverages,

 085 -- Caribbean, Northern South America, Africa (about 350 meters length)

 125 -- Southern South America (about 200 meters in length)

 195 -- Long path Eastern Europe and Scandinavia (reverse direction of 015)

 225 -- Long path Eastern Europe and Scandinavia, Australia, New Zealand
(reverse of 045)

 265 -- Southeast Asia, Western Pacific, Northern Australia (reverse of 085)

 305 -- Japan, China, northern Asia. (reverse of 125)

This Beverage system came online on February 16 and the VP6DX Team said it
"has been an outstanding success in reducing tropical thunderstorm static,
improving our ability to copy weak signals and look for unusual propagation

The Ducie Island DXpedition members summed it up, saying, "All this
hardware is here on Ducie Island to help make it easy for you to contact
us. No matter how simple your antenna, or distant your location, please
check our transmit frequencies. If you can hear us, we can probably hear
you -- so give us a call! Even a make-shift temporary antenna should yield
some surprising results. But hurry! On-air operations will shut down soon
as we prepare to return home." -- Information provided by VP6DX Team

Peter Laws / N5UWY
National Weather Center / Network Operations Center
University of Oklahoma Information Technology
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Feedback? Contact my director, Craig Cochell, [log in to unmask] Thank you!