Some engineering aspects of magnetic tape system design

The design of a digital magnetic tape system requires a detailed knowledge of many effects, some of which by their random and transient nature are difficult to evaluate. Proposals are made for the evaluation of many of these effects in terms of specific measurements on waveforms generated by standard tapes, rather than in terms of dimensional tolerances. Suitable standard tapes are defined in the appendices, together with description of some methods by which they might be prepared; some selected definitions of related terms are also given. By adopting the technique of worst-case design, specifications can be placed on the performance parameters of the system and its components, which are consistent with design for the standard of reliability demanded of modern data processing systems. Such a technique necessarily leads to a modest system specification. Some of the factors described can be removed from the system by proper design, and the method described permits such improvements to be evaluated. In general the system performance is limited ultimately by noise and by random mechanical effects.