Radiotelephone installations

(1) The radiotelephone installation shall include transmitting and receiving equipment (referred to hereinafter as the transmitter, the receiver and the radiotelephone distress frequency watch receiver respectively) and appropriate sources of energy required by regulation 112. (2) The transmitter shall be capable of transmitting on the radiotelephone distress frequency and on at least one other frequency in the bands between 1.605kHz and 3.800 kHz using the classes of emission assigned by the Radio Regulations for these frequencies. In normal operation a single sideband transmission with full carrier shall have a depth of modulation of at least 70% at peak intensity. Modulation of a single sideband transmission with reduced or suppressed carrier shall be such that the intermodulation products shall not exceed the values given in the Radio Regulations. (3) The transmitter shall produce a power in the antenna of at least 60 w for single sideband full carrier emissions. In any case the transmitter shall have a minimum range of at least 75 miles. (4) The transmitter shall be fitted with a device for generating the radiotelephone alarm by automatic means so designed to prevent actuation by mistake. Merchant Ships (Registration) 208 The device shall be capable of being taken out of operation at any time in order to permit the immediate transmission of a distress message. Arrangements shall be made to check periodically the proper functioning of the device on frequencies other than the radiotelephone distress frequency using a suitable artificial antenna. (5) The device required by subregulation (4) shall comply with the following requirements– (a) the tolerance of the frequency of each tone shall be ± 1.5 %; (b) the tolerance on the duration of each tone shall be ± 50 milli-seconds; (c) the interval between successive tones shall not exceed ± 50 milli-seconds; and (d) the ratio of the amplitude of the stronger tone to that of the weaker shall be within the range 1 to 1.2. (6) The receiver required by this regulation shall be capable of receiving the radiotelephone distress frequency and at least one other frequency available for maritime radiotelephone stations in the bands between 1,605 kHz and 3,800 kHz, using the classes of emission assigned by the Radio Regulations for such frequencies. In addition, the receiver shall permit the reception of such other frequencies, using the classes of emission assigned by the Radio Regulations, as are used for the transmission by radiotelephony of meteorological message and such other communications relating to the safety of navigation as may be considered necessary by the Administration. The receiver shall have sufficient sensitivity to produce signals by means of a loudspeaker when the receiver input is as low as 50 microvolts. Merchant Ships (Registration) 209 (7) The radiotelephone distress frequency watch receiver shall be preset to the distress frequency. It shall be provided with a filtering unit device to silence the loudspeaker in the absence of a radiotelephone alarm signal. The device shall be capable of being easily switched in and out and may be used when, in the opinion of the master, conditions are such that maintenance of the listening watch would interfere with the safe navigation of the ship. (8) To permit rapid change-over from transmission to reception when manual switching is used, the control for the switching device shall, where practicable, be located on the microphone or the telephone handset. (9) While at sea, there shall be available at all times a main source of energy sufficient to operate the installation over the normal range required by 5.9.3. Where batteries are provided they shall under circumstances have sufficient capacity to operate the transmitter and receiver for at least 6h continuously under normal working conditions. (10) While at sea, any battery provided shall be kept charged so as to meet the requirements of this regulation. (11) An antenna shall be provided and installed and, if suspended between supports liable to whipping, shall be protected against breakage. In addition, a spare antenna shall be carried on board completely assembled for immediate replacement and where this is not practicable, sufficient antenna wire and insulators to enable a spare to be erected. The necessary tools to erect an antenna shall be provided.