International projectionist (Jan 1959-Dec 1960)

bers, proposed a plan whereby the three school systems could exchange benefits with each other through closed-circuit TV. This plan incorporated four basic questions, the first phrase of each being "by using TV facilities": Prime Questions Posed 1. Can pupils in small schools have the advantages of services usually found only in large schools? 2. Can teaching talent be extended successfully into more than one classroom at a time? 3. Can the level of learning be raised? 4. Can schools provide courses which are now prohibited by excessive cost? In the city of Cortland, there are about 4500 pupils housed in five elementary schools and one junior-senior high school. In Truxton Central School there are 600 pupils in grades K through 12. In Virgil Central School there are 400 pupils in grades K through 12. By committee action it was decided to equip all second and fifth grade rooms in the elementary schools and a number of high school rooms in the three systems with TV receivers. It was further decided to teach science to the elementary school grades, and basic art, English, health, and mathematics to high school pupils. Teaching schedules began on September 29, 1958. System Design Requirements This system, because of its uniqueness, offers great promise and already has aroused much interest. To serve as headquarters for the project and to house the studios, the city of Cortland Board of Education released a two-room elementary school building no longer in use. The Board has refurbished the building. While origination may take place at any of the six Cortland schools, teaching is done in the modern studios at the once "little red school house." Studios, control rooms, and classrooms have been equipped with electronic and TV items by the State Education Department. Radio-frequency distribution and independent talkback systems have been installed by the New York Telephone Co., and are being rented by the Department. The total system was planned with specific operating conditions in mind, some of which are: Specific Operating Conditions 1. Pupils should be able to see in full detail all of the intelligence transmitted by the TV cameras without distraction or distortion. 2. Camera chains should be capable of faithfully reproducing the full intelligence in a picture, microscopic slide, printed matter, movie or transparency. 3. Natural atmosphere of a classroom should be retained in the viewing room. 4. Pupils should be able to hear all sounds without distortion, distraction, discomfort, or undue effort. 5. Pupils should be able to ask questions and receive immediate answers from the studio teacher. 6. System should be designed as an educational communications center capable of serving the entire school community with live lessons, motion pictures, slides, special programs and demonstrations, stereophonic recordings, and two-way audio programs. 7. System should permit separate transmissions to elementary and secondary schools simultaneously. To meet these objectives two fully equipped studios and two radio-frequency channels have been provided. In addition, adequate distribution systems within each school, including high quality receivers, have been installed. [ED.'s NOTE: Data relative to studio design and equipment and the classroom equipment and its utilization will be presented in subsequent issues, beginning with the next.] Sound SCHEMATIC OF CLOSED-CIRCUIT TV CABLE ROUTE, CORTLAND, N. Y. Cable Route closed circuit EDUCATIONAL TELEVISION in Cortland County ve r 5 us Noise People who live next to the railroad tracks find — after a few sleepless nights — that human beings have a remarkable capacity to adjust to irritating sounds. Psychologists have learned, however, that while the conscious mind may shut out bothersome noise, the "inner man" continues to be irritated. Watch a man listening to a phonograph or a tape recorder with a high noise level, and you'll see these principles in operation. Over a period of time listener fatigue multiplies, until finally there is an irresistible impulse to turn the machine off — even though there has been no specific awareness of the background noise. Signal-to-Noise Ratio Of course, every machine makes a little noise, even the finest highfidelity equipment. In judging quality, studio engineers use the signalto-noise ratio of a machine as a measure. Reduced to its simplest terms, the signal-to-noise ratio is the difference between the loudest electrical signal the machine can reproduce satisfactorily and the electrical noise it produces. It is always stated in decibels (db). The greater the signal-to-noise ratio, the less obtrusive the noise. In tape recording and playback, most noise is caused by the machine. But some may also be contributed by the recording tape. This particular kind of noise, however, is very easily avoided. If you want more information on tape recording, you'll be interested in a book called "How To Make Good Tape Recordings." Write for free descriptive folder, Bulletin T. Box AA, Audio Devices, 444 Madison Avenue, New York 22, N. Y. Unicorn's Tape Splicing Kit Unicorn Engineering Corp.'s new programming tape splicing kit Model A4809 makes secure and precise overlapping or INTERNATIONAL PROJECTIONIST MARCH 1959 17