Radio Broadcast (May 1928-Apr 1929)

RADIO BROADCAST ADVERTISER 231 Letters from Readers ■ :l ' What a Vacuum Tube Can't Do ANOTHER good fiction — and this one countenanced by Radio Broadcast — has received its death blow at the stern hands of reality. Witness this letter: To the Editor: With no thought of destroying the sentiment of the interesting and informative article, "The Haven of a Sea-going Audion," in the June issue of Radio Broadcast, 1 would like to protest the author's theory that the audion "may have started in the Atlantic, bobbed through the Canal, crossed the Pacific, etc." If he were to visit the Canal (I presume he means the Panama Canal) he would find that it would be impossible for any floating object to drift through from one ocean to the other. The level of Gatun Lake is eighty odd feet above the sea. The water used in raising and lowering ships in the locks as they enter or leave the Canal comes from the lake, and flows to the sea through the locks at either end of the Canal. The frail glass bulb would have a poor chance reaching the lake against such a counter current thus created. This is the second time in the last two or three years I have noticed the same mistake in the press. The general public is obsessed with the mistaken notion of things floating through the Panama Canal from one ocean to the other. Don't you think a correct impression ought to be made? R. S. Fulton, Radio Operator, S.S. Hochelega Greenwich Mean or Civil Time? THE list of short-wave transmissions which appeared in the May number of Radio Broadcast has brought forth several interesting letters in regard to the confusion existing about the meaning of the terms "Greenwich Mean Tin*e" (G. M. T.) and "Greenwich Civil Time" (G. C. T.) The list of short-wave stations was reprinted from Wireless World, London, England, and retained the time designations of the English magazine. Radio Broadcast also printed in the May number (page 53) a conversion table for G. C. T„ G. M. T., and 75th meridian time (E. S. T.) That this conversion table was in error is shown by the following letter from C. S. Freeman, Superintendent of the U. S. Naval Observatory in Washington D. C. To the Editor: It is unfortunate that the usage of the terms "Greenwich Mean Time" and "Greenwich Civil Time" is not the same in the United States and foreign countries. Originally the term " Mean Time" was universally used to refer to a day beginning at noon, but on January 1, 1925, an international agreement went into effect by which the use of such time was discontinued, and all solar time computed beginning from midnight. In the United States this new time was designated as "Civil Time," but foreign countries retained the designation " Mean Time." Both these designations therefore now refer to the same kind of time. Your table (page 53) should read: G. C. T. or G. M. T. Hours 0 6 12 14 18 22 24 75TH MERIDIAN (E. S. T.) 7:00 P. M. 1:00 A. m. 7:00 A. M. 9:00 A. m. 1:00 P. M. 5:00 P. M. 7:00 P. M. It should be noted, however, that the expression "24 hours" is not in use, "o hours" being in use instead. In your table all the 75th meridian times are marked " p. m.," although the second, third, and fourth should be marked "a. m." (Continued on page 233) QUALITY PRODUCTS The Logical Source on Parts Scientifically designed and Precision Built Audio and Power Transformers, Chokes and Fixed Condensers — every single one fundamentally correct and guaranteed by one of the oldest manufacturers in the industry. Naturally Dongan has been chosen as the source of supply by so many of the substantial companies who have learned that Dongan usually is the first to introduce the new designs and can be depended upon to foster nothing that smacks of the freakish. Filter Condensers Illustrating one of 9 types of Filter Condensers. Built in all capacities for use with filter circuits and power amplifiers. Exceptionally high insulation and permanent stability. 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