3793485 is referenced by 16 patents and cites 2 patents.

A precision automatic audiometer adapted to test the hearing of an individual utilizes a voltage programmable oscillator in combination with a preprogrammed logic circuit to generate a predetermined series of hearing test tones into a suitable earphone worn by the individual being tested. A novel solid state voltage proportional attenuator being controlled by examinee manually operated switch means enables an examinee being tested to regulate the level of sound pressure to which he is being exposed, while a chart recording instrument simultaneously graphs the audiogram of his test responses.

Title
Precision automatic audiometer
Application Number
05/315,173
Publication Number
3793485
Application Date
December 14, 1972
Publication Date
February 19, 1974
Inventor
Preslar Mack J
Feezor Michael D
Assignee
Audiometric Teleprocessing
IPC
H04r 29/00
A61B 05/12
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