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Merchant Shipping Act, 1951 (Act No. 57 of 1951)

Schedules

Second Schedule

Protocol of 1978 Relating to the International Convention for the Safety of Life at Sea, 1974

Annex

Chapter IV : Radiotelegraphy and Radiotelephony

Part C — Technical Requirements

Regulation 16 : Radiotelephone installations

 

(a) The radiotelephone installation shall include transmitting and receiving equipment, and appropriate sources of energy (referred to in the following paragraphs as “the transmitter”, “the receiver”, “the radiotelephone distress frequency watch receiver”, and “the source of energy” respectively).

 

(b) The transmitter shall be capable of transmitting on the radiotelephone distress frequency and on at least one other frequency in the bands between 1 605 kHz and 2 850 kHz, using the classes of emission assigned by the Radio Regulations for these frequencies. In normal operation a double sideband transmission or a single sideband transmission with full carrier (i.e., A3H) shall have a depth of modulation of at least 70 per cent at peak intensity. Modulation of a single sideband transmission with reduced or suppressed carrier (A3A, A3J) shall be such that the intermodulation products shall not exceed the values given in the Radio Regulations.

 

(c)        

(i) In the case of cargo ships of 500 tons gross tonnage and upwards but less than 1 600 tons gross tonnage the transmitter shall have a minimum normal range of 150 miles, i.e., it shall be capable of transmitting clearly perceptible signals from ship to ship by day and under normal conditions and circumstances over this range. (Clearly perceptible signals will normally be received if the R.M.S. value of the field strength produced at the receiver by the unmodulated carrier is at least 25 microvolts per metre.)
(ii) In the case of cargo ships of 300 tons gross tonnage and upwards but less than 500 tons gross tonnage—
(1) for existing installations the transmitter shall have a minimum normal range of at least 75 miles; and
(2) for new installations the transmitter shall produce a power in the antenna of at least 15 watts (unmodulated carrier).

 

(d) The transmitter shall be fitted with a device for generating the radiotelephone alarm signal by automatic means so designed as to prevent actuation by mistake. 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.

 

(e) The device required by paragraph (d) of this Regulation shall comply with the following requirements:
(i) The tolerance of the frequency of each tone shall be ±1,5 per cent.
(ii) The tolerance on the duration of each tone shall be ± 50 milliseconds.
(iii) The interval between successive tones shall not exceed 50 milliseconds.
(iv) The ratio of the amplitude of the stronger tone to that of the weaker shall be within the range 1 to 1,2.

 

(f) The receiver required by paragraph (a) of 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 2 850 kHz, using the classes of emission assigned by the Radio Regulations for these 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 messages 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 speaker when the receiver input is as low as 50 microvolts.

 

(g) The radiotelephone distress frequency watch receiver shall be preset to this frequency. It shall be provided with a filtering unit or a 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.

 

(h) To permit rapid changeover 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.
(i) While the ship is 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 paragraph (c) of this Regulation. If batteries are provided they shall under all circumstances have sufficient capacity to operate the transmitter and receiver for at least six hours continuously under normal working conditions. In installations in cargo ships of 500 tons gross tonnage and upwards but less than 1 600 tons gross tonnage made on or after 19 November 1952, a reserve source of energy shall be provided in the upper part of the ship unless the main source of energy is so situated.

 

(j) The reserve source of energy, if provided, may be used only to supply—
(i) the radiotelephone installation;
(ii) the emergency light required by paragraph (d) of Regulation 15 of this Chapter;
(iii) the device required by paragraph (d) of this Regulation, for generating the radiotelephone alarm signal; and
(iv) the VHF installation.

 

(k) Notwithstanding the provisions of paragraph ( j) of this Regulation, the Administration may authorize the use of the reserve source of energy, if provided, for a direction finder, if fitted, and for a number of lowpower emergency circuits which are wholly confined to the upper part of the ship, such as emergency lighting on the boat deck, on condition that the additional loads can be readily disconnected, and that the source of energy is of sufficient capacity to carry them.

 

(l) While at sea, any battery provided shall be kept charged so as to meet the requirements of paragraph (i) of this Regulation.

 

(m) An antenna shall be provided and installed and, if suspended between supports liable to whipping, shall in the case of cargo ships of 500 tons gross tonnage and upwards but less than 1 600 tons gross tonnage be protected against breakage. In addition, there shall be a spare antenna completely assembled for immediate replacement or, where this is not practicable, sufficient antenna wire and insulators to enable a spare antenna to be erected. The necessary tools to erect an antenna shall also be provided.