Page:United States Statutes at Large Volume 63 Part 2.djvu/570

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63 STAT.] MULTILATERAL-TELECOMMUNICATIONS-OCT. 2 , 1947 (Chapter XIII, art. 33 RR) (762-769) B. Call and Reply. 762 § 19. (1) In order to establish communication with a station in the maritime mobile service, every ship and aircraft station must use a calling frequency in the bands listed in 775. 763 (2) Frequencies in the calling bands are assigned to each mobile station in accordance with the provisions of 776 to 780 inclusive. 764 § 20. In order to reduce interference, mobile stations must, within the means at their disposal, endeavour to select for calling the band with the most favourable propagational characteristics for effecting reliable communication. In the ab- sence of more precise data, a mobile station must, before mak- ing a call, listen for the signals of the station with which it desires to communicate. The strength and readability of such signals is a useful guide to propagational conditions and should indicate which is the preferable band for calling. 765 § 21. (1) The calling frequency to be used by a coast station, in each of the bands for which it is equipped, is its normal working frequency as shown in heavy type in the List of Coast and Ship Stations (see 774). 766 (2) A coast station, as a general rule, transmits its calls at specified times in the form of traffic lists on the frequency or frequencies indicated in the List of Coast and Ship Stations (see 685 and 686). 767 § 22. Unless the calling station specifies otherwise, the frequency for reply to a call made in any maritime mobile band is as follows: 768 a) for a mobile station, its assigned calling fre- quency in the same band as that used by the calling station; 769 b) for a coast station, its normal working fre- quency in the same band as that used by the calling station. 81939 0-52 - - IT. 11- 1867 -37