RADIO COMMUNICATIONS 



One of the most important features of the ice patrol work is an 

 efficient and consistent performance of radio communication ; in fact, 

 the success of the patrol lies to a great extent in correctly accumulat- 

 ing and disseminating the ice and obstruction information. The ice 

 area, moreover, which is kept under surveillance by the patrol ship, 

 is greatly enlarged by the information received over the radio from 

 ships scattered throughout the entire ice regions. The operations of 

 1927, as in past years, revealed excellent cooperation on the part of 

 the merchant vessels and the shore stations; a spirit which is highly 

 gratifying to the patrol. We desire also to add that the Canadian 

 direction-finding stations. Cape Race commercial radio station, and 

 bordering United States naval radio stations have done all possible 

 to facilitate the patrol radio communications. 



We are impressed, when making a survey of the radio work of 

 1927, with the fact that schedules between the United States naval 

 radio stations and the patrol ship were maintained more consistently 

 than ever before. This condition is attributed, first, to the higher 

 power used this year by naval stations, and, second, to the personal 

 cooperation shown by the individual operators both ashore and afloat. 

 In previous years, too, ship-to-shore communication has often been 

 interrupted by summer-time static conditions, but this difficulty in 

 1927 was seldom encountered, and then for short periods only. 



The radio equipment carried on board the patrol vessels was prac- 

 tically the same as that used in 1926. (See Bulletin No. 15.) The 

 high-frequency experimental receiver was replaced by a new type 

 called the "R.G." high-frequency receiver, the latter being a later 

 model, better constructed, possessing a wider range of frequencies, 

 and also being more sensitive than the older receiver to weak signals. 

 The R.G. receiver proved itself far superior both in ease of control 

 and signal amplification than any of the former types of apparatus. 

 The XA 500-watt high-frequency transmitter was the same as that 

 used last year with the exception of several alterations made at the 

 Navy experimental laboratory, Bellevue, Md., during the winter of 

 1926-27. Improvements included easier adjustment on specified 

 frequencies, and installation of a plate overload relay, in order that 

 damage would not result because of sudden rise of plate voltage. 

 The only trouble experienced with any of the apparatus during the 

 patrol occurred on board the Tampa, where a variable ground devel- 

 oped in the high-voltage leads of the 2,500-volt main radio motor 



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