47 U.S.C. § 354a — Technical requirements of equipment on radiotelephone equipped ships

Cargo ships between 300 and 1,600 gross tons may use a radiotelephone station instead of the radiotelegraph station required by section 354, as long as it meets these requirements: (a) Location. The radiotelephone station must be in the upper part of the ship, positioned to be sheltered as much as possible from noise that could interfere with correctly receiving messages and signals. Unless the station is located on the bridge itself, there must be an efficient way to communicate with the bridge. (b) Frequencies. The installation must be able to transmit and receive on the frequencies, and using the classes of emission, that the Commission designates for distress and navigation-safety purposes. (c) Range. The installation must have a minimum normal range of 150 nautical miles — meaning it must be able to send and receive clearly perceptible signals ship-to-ship in daylight, under normal conditions, over that distance. (d) Power. A main source of electrical energy must be available at all times, strong enough to run the installation over its required range. If batteries are used, they must have enough capacity to run the transmitter and receiver for at least six continuous hours under normal working conditions. For installations made on or after November 19, 1952, a backup source of electrical energy must also be placed in the upper part of the ship, unless the main power source is already located there.