High-speed duplication of magnetic tape recordings

The high-speed duplication of previously recorded magnetic tapes has made the tape radio network practical. For example, each of the two major radio networks in Mexico duplicates over 19,000 seven-inch reels of taped programs per month for their several hundred affiliated stations. Since the tapes are erasable and wire program circuits are seldom used, these networks operate very economically, and the quality of their recorded programs is unimpaired by losses in transmission. Likewise, the adoption of Automatic Programming Systems for radio broadcasting will create a demand for syndicated magnetic tape programs and tape libraries. High-speed magnetic tape duplicators are also utilized for the mass production of tape recordings for entertainment, education, churches, libraries for the blind, reviews of professional publications, and sales information for large field sales organizations. The Ampex Model S-3200 tape duplicator with ten slaves will produce up to ten copies at one time of 15, , or ips master recordings at 60 ips. The copies can be recorded to be reproduced either at the speed of the master or at half speed; i.e., ips copies from a ips master. The duplicates may be either half-track, double-track, full-track, or two-track stereophonic. Comparisons are made of the degradation of the signal-to-noise ratio, frequency response, and distortion with respect to the number of generations of the duplicates. With optimum adjustment of the equipment, it is very difficult to identify the fourth generation copy from the master recording.