Page:United States Statutes at Large Volume 49 Part 2.djvu/463

 TELECOMMUNICATION CONVENTION. DECEMBER 9, 1932. 2479 ARTICLE 9 OondiJions to be Observed by Mobile Stations A. GENERAL [l32J § 1. (1) Mobile stations must be established in such a way as to conform, as regards frequencies and types of waves, to the general provisions forming the subject of article 7. [133] (2) In addition, no new type-B -wave transmitter installa- tion shall be made in mobile stations, except when these transmitters, working at full power, use less than 300 watts measured at the input of the audiofrequency supply transformer. (134] (3) Finally, the use of type-B waves on all frequencies shall be forbidden, beginning with January 1, 1940, except for trans- mitters fulfilling the same conditions as above regarding power. [135] § 2. The frequency of emission of mobile stations shall be veri- fied as often as possible by the inspection service to which they are subject. (136] § 3. Receiving apparatus must be such that the current which they induce into the antenna shall be as low as possible and shall not disturb neighboring stations. (137] § 4. Transmitting and receiving sets of any mobile station must permit of making frequency changes as rapidly as possible. All installations must be such that, after the communication is estab- lished, the time necessary to change from transmission to reception and vice versa shall be as short as possible. B. SHIP STATIONS Conditions to be ob- served by mobile sta- tions. General. Ante, p. 241i3. £138] § 5. (1) The transmitting apparatus used in ship stations Sblp statioWl. working on type-A2 or -B waves in the authorized band between 365 and 515 kc (822 and 583 m) must be provided with devices making it possible conveniently and appreciably to reduce the power thereof. (1891 (2) This provision shall not apply to transmitters in which the power, as measured at full load, does not exceed 300 watts on the transmitting-tube plates (type-A2 emission) or at the input of the audiofrequency supply transformers (type-B emission). [140] (3) All ship stations transmitting on frequencies in the band 100 to 160 kc (3,000 to 1,875 m) and on frequencies above 4,000 kc (wavelengths below 75 m) must be equipped with a wave meter having a precision at least equal to 5/1000, or with an equivalent device. (141] § 6. Any station installed on board a ship, compulsorily pro- vided with radio apparatus as a result of an international agreement, must be able to transmit and to receive on the wave of 500 kc (600 m), type-A2 or -B and, in addition, on at least one other type-A2 or -B wave, in the authorized band between 365 and 485 kc (822 and 619 m).