Abstract: Apparatus for enabling a blind person to determine the status of a plurality of telephone lines from the illumination condition of signal lamps associated therewith which respectively indicate the "ON", "OFF", "RING" or "HOLD" status of each line. Photosensors sense the illumination condition of each lamp and provide first signals in response thereto. The apparatus sequentially and repetitively scans the photosensors and the resultant sequentially appearing first signals are serially and repetitively converted to digitally coded signals which are serially read-into storage means. Means are provided for sequentially and repetitively generating a plurality of audio tone signals respectively having progressively different frequencies, each tone signal corresponding to a particular line. The coded signals are serially read-out of storage at the rate of the tone signal generation and are serially decoded.
Abstract: Apparatus for providing auditory and tactile recognition of a light signal associated with a line-selector pushbutton of a multi-line telephone instrument. A photocell is provided for sensing the light signal. An oscillator generates a sine wave voltage which is amplified and applied to excite a piezoelectric crystal into vibration in response to activation of the photocell. An auxiliary pushbutton is disposed in alignment with the line selector pushbutton so that manual depression of the auxiliary pushbutton actuates the line selector pushbutton. Vibration of the crystal in response to the light signal acts upon the auxiliary pushbutton to impart the vibration thereto so that the presence of a light signal is sensed by vibration of the auxiliary pushbutton.