Engineering procedures used in the design and construction of a high-speed, multichannel magnetic tape duplicator are described. The completed duplicator, a common mandrel duplicator, in which a single drive motor turns a common capstan shaft at high speeds and moves both master and copy tapes simultaneously, performs satisfactorily yet suggests…

With the growth of computer technology, bibliographic data bases have developed into sophisticated online research tools. The major data bases are produced by abstracting and indexing (A&I) publishers. Vendors purchase the A&I publishers' machine readable tapes, then sell computer access to the tapes to information based organizations such…