Magnetic Recording and Some of Its Applications in the Broadcast Field

Broadcast stations in this country today depend upon mechanical recording as the only means of storing a program for delayed transmission or for reference purposes. Magnetic recording, which has been frequently used in Europe, has not as yet been introduced into this country in the broadcast field although, because of its characteristics, it has some definite advantages. The magnetic sound carrier has the outstanding feature that it can be repeatedly used for new recordings without any deterioration. On the other hand, a magnetic impression on the sound carrier is not harmed by repeated reproduction. Magnetic recording is, therefore, particularly suitable where time delay in transmission or many repetitions of the same program material are required. This paper will deal briefly with the three essential processes of magnetic recording: the obliterating, the recording, and, finally, the reproducing of a record. The magnetic material to be used will be discussed briefly as will some other necessary electrical and mechanical requirements for obtaining a desired frequency and dynamic range. Reference will be made to applications of magnetic recording systems by European broadcast stations for program delay. Furthermore, a unit will be described which permits short time delays and thus can be used either for producing artificial reverberation or artificial echo. Magnetic recording, in addition to this, promises to be applicable for "spot" announcements.