The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 23, 1977
Filed:
Jun. 27, 1975
James W Justice, Murrysville, PA (US);
Marcus H Uhler, Pittsburgh, PA (US);
Westinghouse Electric Corporation, Pittsburgh, PA (US);
Abstract
In an educational television system, a constructed answer system is based on the use of code pulses that are repeated cyclically during their concealed transmission within a television video waveform. Indicia, e.g., letters of a word or formula, are preloaded into a store in the form of binary code as an output from a punched tape reader or an encoder for a keyboard. The encoder is reset following each transfer of encoded indicia to the store which is indexed by a shift register to render responsive successive columns of flip-flops in a matrixed arrangement. The store includes a column of AND gates to store a permanent 'recycle code'. The reading of the store is clocked by modified sync pulses applied by a shift register to a matrix arrangement of interconnected AND gates that are also connected to the output of the flip-flops. The readout of the store is repeated cyclically by a logic register that compares the number of encoded indicia in the store with the number of encoded indicia read from the store. Further circuitry, using AND gates, is responsive to a student keyboard to compare the student response with the decoded indicia signals to determine a correct response.