News #21- 2008 Feb 25
Long path contacts on 160m with Ducie Island
Earlier, we reported that a contact on the 160m band had been made with A45XR in Oman, at the opposite side of the planet from Ducie Island. This contact occurred on Feb 18 near Ducie Island sunrise. All of the stations contacted in Europe were in their late afternoon, with the sunset terminator approaching.
On Feb 21 a series of long path 160m contacts were made between Ducie Island and stations in Ukraine and southern European Russia. Eleven stations were worked during 1345-1430z. 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 23000 to 24000 km 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 towards 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 015 degree beverage antenna and was barely audible on the 195 antenna.
Scandinavia and northwest Russia stations looking for a 160m 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.
Of course, we looked for the same opening the following morning, but without success. The 160m operator team will keep checking through the final day of operations. Departure from Ducie Island, now scheduled for February 28 Thursday at 2000z, 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
We have received inquiries about the equipment and antennas used on Ducie Island.
Each operating position uses:
- Elecraft K3 radio. The outstanding receiver and transmitter characteristics allow us to run two positions simultaneously on any band -- even the very narrow 30m 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 160m includes an OM 2500 HF amplifier.
- 200 W W3NQN bandpass filters from Array Solutions and 2 kW bandpass filters from 4O3A.
- WinTest logging software runs on Durabook ruggedized laptops.
- Honda EM65is and EM30is inverter supply, gasoline generators -- 100% 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 1km apart, a 15 minute walk over a coral shelf bordering the island's inner lagoon. Each site has its own WiFi network, and a microwave link ties the two sites together. Sleeping tents and meals are located at the east camp.
The antennas include:
- 160m: Titanex vertical. (west)
- 80m/30m CW: Titanex vertical. (west)
- 75m SSB: SpiderBeam 4-square. (east)
- 40m: two SpiderBeam 4-squares. (one at each site)
- 30m: Spiderbeam 4-square. (east)
- 20 thru 10m: two Spiderbeam 2-element vertical Yagi arrays on each band, one located at each site.
- 6m: 5-element Yagi
An array of beverage receiving antennas sits mid-way 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 160m, 80m CW and 75m 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 K3NA and W2VJN. On-site construction was done under the hot sun by Robin WA6CDR and Milt N5IA (who sacrificed most of their operating time to date to make this happen!)
Receive antenna directions available to the operators are:
- 015 - western USA, eastern Europe short path. (about 200m in length)
- 045 - eastern USA, western Europe (two parallel 200m beverages, combined)
- 085 - Caribbean, northern South America, Africa. (about 350m length)
- 125 - southern South America (about 200m in length)
- 195 - long path eastern Europe & Scandinavia (reverse direction of 015)
- 225 - long path eastern Europe & 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 on-line on Feb 16 and has been an outstanding success in reducing tropical thunderstorm static, improving our ability to copy weak signals and look for unusual propagation paths.
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.
New pictures online
Have a look at http://ducie2008.dl1mgb.com/pictures/index.php.
We would be delighted if DX editors would publish this information as widely as possible and DXers bring it to the attention of their clubs and fellow DXers.
Small test for Topbanders -> WHO IS AT THE KEY ON THE PICTURE IN THE BEGINNING OF THAT ARTICLE ? Your tips You can put to comment below the article...
73, Petr OK1RP