captains only use the recorder intermittently to conserve recording 

 paper. This defeats one of the main functions of the instrurient, i.e., 

 detecting rough bottoms where gear might be lost. 



Radio Telephone 



A radio telephone is intended to function as a navigational 

 instrument. When used in conjunction vith a searchlight or other 

 visual aids, it enables a vessel to be "talked in" to a group of ves- 

 sels already on tne fishing ground. In the Harvjell, Knowles and 

 Associates sample of vessels, transmitters used in connection with 

 radio telepnones ranged from an output of 5 watts to the maximum 

 permissible of 150 watts, with some sets even exceeding this limit. 

 Vessels fishing close to shore had either no radio telephone or an 

 installation of low wattage. At the other extreme were vessels fishing 

 in the Gulf of Campeche which had equipment capable of producing the 

 raaxiirium permissible povjer output. 



Three types of aerials were in use. In tne South Atlantic 

 and Tortugas Areas tne wire-coiled bamboo pole type was predominant. 

 On newer vessels in the same area a metal antenna was common. In 

 Texas, especially in the Brownsville fleet, so-called "flat top" tjrpe 

 aerials were being used. The latter were copper wires strung from 

 the boom via the mast to the bow of the vessel. 



The service life of the bamboo type of aerial v;as estimated 

 to be about one year. By then moisture absorbed by the baraboo would 

 reduce the signal strength transmitted. The metal type aerial was 

 considered to be more efficient than the bamboo type and was supposed 

 to last approximately three years. The "flat top" aerial was found 

 to be tne most durable, efficient, and economical of the three types 

 in i^e and was gaining steadily in popularity throughout tne fleet. 



Failure to adhere to the proper standards for use and upkeep 

 of the radio equipment on the part of captain and crew diminished the 

 banel'it derived from the installation in some instances. Sets aboard 

 some snrirap vessels were found to be inoperative because the 32-volt 

 bank of batteries was chargad by generators with tne voltage regulator 

 sot to cut out at about 36 volts. The constant overload on the elec- 

 tronic equipment shortened the life of tne tubes, resistors, condonsors, 

 etc., in the sets. 



Use of improper crystals in the tuning circuits waq found to 

 be a major cause of sipjnal output reduction in some instances. Some 

 technicians fail to recognize the need for precise compliance witn the 

 requirei.ients for crystals in each make and type of set. 



Attempts to repair sets by tecnnicians unfamiliar with a 

 particular set, or worse even, by captain and cre^^ members themselves, 

 were responsible for the poor condition of some sets. Inadequate 



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