FERROELECTRIC TAPE RECORDING AND REPRODUCING PROCESSES.

The development in recent years of ferroelectric materials suggests the possibility of a new method of tape recording. It is the purpose of the study to investigate this possibility. After a theoretical discussion of ferroelectricity, and of tape recording in general, the results of several experiments are presented. The most successful of these employs longitudinal recording on a plastic tape, coated with ferroelectric material. True ferroelectric signal recording is demonstrated, although it is limited in frequency at the high end and in the duration of the record. Recording at the low frequency end is easily achieved. Smaller recording and reproducing gap widths would make it possible to extend the high frequency range considerably. In one experiment a decay to 13 of the original amplitude occurred in 150 seconds, at a relative humidity of 20. Possible methods of removing the high-frequency and decay limitations are discussed. A comparison with magnetic recording is also given. The most apparent advantages of ferroelectric recording are the ease of reaching very low frequencies, and the possibility of less tape wear through the use of out-of-contact reproducing heads. Author