Radio age research, manufacturing, communications, broadcasting, television (1941)

Radio in Latin America graph equipment for his yacht. In Peru the Compania Nacional de Telefonos (National Telephone Company) has embarked on a pro- gram of modernization which in- cludes provision for radiotelephone service connecting five of the coun- try's principal cities—Lima, Are- quipa, Iquitos, Cuzco, and Piura. Used in this project will be the latest design RCA equipment in- cluding: six transmitters, twelve receivers, two control racks at each station, emergency power generat- ing equipment, cage-type antennas and transmitting towers. Installa- tion of three short-wave radio transmitters have been made re- cently aboard ships of the Peruvian Merchant Marine. "Radio America", in Lima, is in- creasing its power to 10 k.w., an- other RCA installation. The Ministry of National De- (Continued from page 28) fense of Venezuela has purchased Radiomarine equipment for 14 ships. Three of the ships are being equipped with transmitters and all are to be equipped with the latest radiotelephone apparatus. Arrangements have been com- pleted for installation of a new 5 k.w. broadcasting station and as- sociated RCA FM broadcast trans- mitter in Barranquilla, Colombia, for the network "Emisores Unidas", managed by Raphael Roncallo. A 10-kilowatt RCA radio broadcast- ing transmitter was recently in- stalled in the city of Medellin for station "Siglo Viente" and its com- panion station "La Voz de Antio- quia." In Puerto Rico, center of intense radio activity, engineers have com- pleted installation of an RCA 10 k.w. medium frequency broadcast transmitter in San Juan for station WAPA, owned by Jose Ramon Quinones. In San Juan, WIAC has inaugu- rated an attractive new air-condi- tioned building, especially designed for modern broadcasting, and RCA equipped. The newspaper "El Mundo" of San Juan, is going on the air with an RCA 5 k.w. trans- mitter. From Ponce, the Puerto Rican American Broadcasting Cor- poration station WPAB will cover its market with new RCA 5 k.w. equipment. One of the first stations in Latin America to streamline its facilities and step up its power was station CB 114 in Santiago de Chile. The Argentine government-owned petroleum company, Yacimientos Petroliferos Fiscales, is installing complete RCA radio-telegraph units aboard seven of its oil tankers. Pasteurizing Milk by Radio pure tin which, in turn was sub- merged in a tank of warm water. The milk then flowed through the electrodes and was cooled by pass- ing over a set of fins through which ice water was pumped. When samples of the milk pas- teurized by this method were tasted, however, it was discovered that there was a definite cooked flavor whenever the milk had been heated to 190°F or higher. The importance of maintaining the flavor of milk in any pasteuriz- ing process is well-known to dairy plant operators, and this defect of the process was recognized imme- diately by the scientists. It was decided that the cooling time of approximately 5 seconds ap- parently was too long. More rapid cooling was, however, achieved by injecting the milk stream into a vacuum chamber. The heating time was maintained at 67/1000 of a second but the cooling time by this method was reduced to 2/10 of a second. The milk was cooled to 135°F by means of the vacuum ex- (Continued from page 16) pansion then the milk was poured over cooling fins and reduced to 40-F. Samples for bacteriological tests were taken at the conclusion of the vacuum expansion, and cream vol- ume samples were taken at the lower temperatures. Samples of milk which were tested showed no traces of cooked flavor at any tem- perature used. Even a sample taken at 205 °F could not be differentiated from the raw milk. Bacteria count was reduced to 100 as compared to 48,300 normally found in milk pasterurized by the conventional method at 143 °F for 80 minutes. Bacillus coli was zero as compared to plus two in the con- ventional method. Pasteurization by radio heat is so new that many questions remain as to the exact eff'ect of the method, but perhaps the most striking and promising fact of all is that milk so treated keeps longer than pas- teurized milk which we drink today. While ordinary pasteurization kills most of the biological harmful bacteria found in milk, other non- harmful bacteria stay in the milk and cause it to sour. By eliminating these heat-resistant bacteria, prog- ress has been made toward the de- velopment of a longer-keeping milk. One of the chief limitations of the new process is that it can only be used to produce homogenized milk. However, with greater quan- tities of homogenized milk being sold today than ever before it is conceivable that its acceptance will be widespread in a few years. Experiments worked out by RCA in cooperation with the Walker- Gordon Company and the Borden Company, large Eastern dairy prod- ucts producers, provide for a con- tinuous radiation treatment which promises a possible foreshortening of milk-processing operations. The experiments, however, have been limited to the laboratory and at the present time interest of milk pro- ducers is not deemed sufficient to warrant commercialization of the system. RADIO AGE 31]