25 



During the ninth cruise southwesterly breezes prevailed in the ice- 

 patrol area, making the weather damp and muggy over the 55° to 

 65° water and persistently foggy over the 50° to 55° water. There 

 were no gales, but the patrol before reaching Boston experienced some 

 strong breezes due to the influence of two disturbances whose centers 

 traveled across the Gulf of St. Lawrence. 



RADIO COMMUNICATIONS 



The radio apparatus used on the Tampa and the Modoc during the 

 1929 ice-patrol season was practically the same as that used by the 

 patrol vessels during the 1927 and 1928 seasons. The main changes 

 on each ship were the substitution of improved receivers for older 

 types. Each ship in 1929 had for transmitting purposes one T-2 

 2-kilowatt tube transmitter, using either CW or ICW or phone trans- 

 mission; one T-4 200-watt tube transmitter using either CW or 

 ICW transmission; and one 500-watt XA crystal-control high-fre- 

 quency transmitter. The latter type of set was very useful for clear- 

 ing at scheduled times a large volume of direct traffic with NAA, the 

 United States naval radio station near Washington, D. C. The dis- 

 tance between the patrol vessel on duty and that station averaged 

 about 1,350 sea-miles. 



The receiving apparatus on each ship consisted of one special high- 

 frequency screen-grid receiver, type CGR-24, and one low-frequency 

 receiver, type CGR-25, also screen grid. These receivers were 

 recently manufactured for the United States Coast Guard and were 

 the most up-to-date instruments in the service, being a big improve- 

 ment over old types. They gave very satisfactory results on ice- 

 patrol work. The 1929 receiving equipment included, in addition, 

 the latest type direction finder or radio compass, which was invalua- 

 ble for making quick and sure contact with the vessel coming out 

 to relieve the patrol. Each vessel had also one CGR-1 receiver for 

 use on the Coast Guard frequency band. 



During the season there were no serious breakdowns of either 

 sending or receiving sets. Free use of the good supply of spare parts 

 and immediate rectification of all small troubles that developed 

 combined to keep all apparatus in the radio department close to 

 perfect operating condition at practically all times. 



Normally United States Coast Guard cutters of the Tampa class 

 carr}- four radiomen. While on ice-patrol duty this year, however, 

 each patrol vessel carried in addition one radio electrician. This 

 policy provided the services of an experienced supervisor on each 

 vessel, which proved to be of great benefit, for the year 1929 had not 

 only the longest ice-patrol season to date, but also, from a communi- 

 cations standpoint, b}" far the most arduous one on record. Due to 

 extreme heaviness of schedule traffic, to the great number of ice 



