Patents by Inventor Robert R. C. Buchan

Robert R. C. Buchan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 3946503
    Abstract: An audio-visual unit presents a series of questions and corresponding multiple choice answers on a viewing screen in response to a series of pulses recorded on an audio magnetic tape. When each question is presented, a tone is generated for actuating a question counter, and the tone is automatically recorded on a magnetic tape cassette. An answer is selected by manually actuating a corresponding answer switch which causes a specific differential tone to be generated and also recorded on the magnetic tape cassette. The cassette recorder is momentarily actuated for the recording of each tone and has a series of lights which indicate the corresponding selected answer during both recording and playback. The electrical circuit also provides for quickly bypassing a series of subordinate questions of a program if a particular answer is selected to a primary problem question.
    Type: Grant
    Filed: March 20, 1974
    Date of Patent: March 30, 1976
    Assignee: Robert R. C. Buchan
    Inventors: Robert R. C. Buchan, Robert W. Kirchgessner, Jr.