Page:Popular Science Monthly Volume 88.djvu/179

 Popular Science Monthly

Navy is planning to increase the height of the masts to 500 feet and install a 25 kw. set in addition to the present 5 kw. one. The new set will be of the Poul- sen arc type, for the generation of con- tinuous waves. The station at Unalga Island has been dismantled, and that at Dutch Harbor (Unalaska) will be in- creased in size, to make it capable of handling the traffic heretofor handled by the Unalga station. Unalga and Dutch Harbor are only eighteen miles apart, and it was not deemed necessary to maintain both stations.

These two stations are peculiarly well located for long distance radio work. The station at Unalga Island has several times been in direct communication with the United States Navy station at Key West, Florida, nearly six thousand miles distant, although the power employed at Unalga Island was only ten kw. The operators at Unalga claim to have copied quite regularly, during the winter months, many stations on the Atlantic coast, in spite of the fact that Unalga Island is located more than fifteen hun- dred miles west of the Pacific coastline of the United States. Stations in Japan, Russia, China and the Philippine Islands are heard regularly and were it not for the fact that the Asiatic stations use lan- guages other than English in their regu- lar work, the operators at Dutch Harbor or Unalga Island could easily communi- cate with them.

The station at Wood Island (Kodiak) is one of the most efficient the Navy has in Alaska. This is undoubtedly due largely to its favorable geographical lo- cation. Kodiak is within daylight range of St. Paul (575 nautical miles distant), Cordova (260 miles), and Sitka (530 miles). Occasionally Kodiak has been in daylight communication with Unalga Island, and it is very probable that, when the improvements at the Dutch Harbor station are affected, that station will be in daylight range of Kodiak. The station at Cape Whiteshed (Cordova) has been rather unsatisfactory for long distance work, although this station is equipped in an up-to-date manner with a ten kw. Tclefunkcn set. This may be due to a poor location.

The station at Sitka is one of the first put up by the Navy in Alaska, and has

���Umbrella antenna used on Alaska stations

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done very efficient work, although not until recently has it been equipped with the -latest type apparatus. At present two sets are installed, one being a live kw. Telefunken set, and the other a 20 kw. 240 cycle synchronous rotary dis- charger set.

The installation of vacuum tube am- plifiers in all the Navy stations of Alas- ka, recently, has made a marked improvement in the service ren- dered. Stations that have previ- ously had diffi- culty in main- taining commu- nication are now working without trouble. The working range with vessels is also materially increased thereby, as the amplifiers enable the Navy stations to receive signals from the I and 2 kw. sets on board ships, as far as the ships are able to receive sig- nals from the five and ten kw. equip- ments of the Navy stations, and often- times farther. The Navy has but re- cently inaugurated a new service, where- by vessels in communication with its Alaska stations may send in reports of their positions daily, which are to be re- layed without charge to the Navy sta- tion at North Head, Wash., where the position reports are turned over to the telegraph lines for transmission to the daily papers of the Pacific Coast. By this service, the reports of positions of vessels in Alaskan waters each night, are published in the following morning's pa- pers in all the principal cities of the coast.

Heretofor the Alaskan station have been able to communicate with North Head at night only, but since the in- stallation of the audion amplifiers, day- light service has been possible to a lim- ited extent between North Head and Sit- ka, using waves under 2,000 meters in length. This is over a distance of 780 nautical miles. During the summer months there is but an hour or two of darkness each night, and during the lat- ter part of June and the early part of July, it docs not get even comj)letely

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