Publication Date


Document Type


First Advisor

Newell, Darrell E.||Hamm, Erwin C.

Degree Name

M.S. (Master of Science)

Legacy Department

Department of Industry and Technology


Electronic data processing


An electro-mechanical system was designed, engineered, and constructed capable of recovering information from magnetic computer tape and producing a graphic image. The machine uses an Ampex tape transport to handle and read tape. An Electronics Associates Variplotter, an oscillograph, is used for output. Specially designed circuitry interfaces the two machines. This report covers the research and development of the interfacing circuitry. Operating parameters were empirically derived. An arbitrary signal flow scheme was designed. A flexible development scheme was used. Circuits were built and tested to assure their contribution to the finished product. A special computer program was developed to augment the machine function. Data from a master program is reduced to integer form. Four digit integer coordinate points are recorded preceded by an alphabetic identifier as tape records. Provision was made to record six functions per tape block. A selector mechanism allows individual functions to be graphed from adjacent records. Full advantage was taken of industrial developments in transistor-transistor logic (T²L). A great variety of functions are available in this family of devices. Of special significance was the availability of a digital-to-analog converter that was T²L compatible and provides for linear conversion between binary coded decimal integers and voltage. This fortunate find allowed for simple data handling. A workable plotter system resulted from the effort. The first generation effort was very satisfactory. The machine offers great possibilities for second generation additions or changes.


Includes bibliographical references.||Includes illustrations.


vi, 96 pages




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