Abstract: A device and method is disclosed to correct intonation errors and generate vibrato in solo instruments and vocal performances in real time. The device determines the pitch of a musical note produced by voice or instrument and shifts the pitch of that note to produce a very high quality, high fidelity output. The device includes a pitch detector that automatically recognizes the pitch of musical notes quickly. The detected pitch is then used as an input to a pitch corrector that converts the pitch of the input to an output with a desired pitch. The corrected musical note is then in tune with the pitch standard. The device and method employ a microprocessor that samples the signal from a musical instrument or voice at regular intervals using an analog-to-digital converter and then utilizes data derived from an auto-correlation function of the waveform to continuously determine the period of the waveform. The period of the waveform is then compared to a desired period or periods (such as found in a scale).

Abstract: A gas regulator valve (14) for maintaining a preset low gas pressure in a storage tank (10). A fluid balanced piston valve member (32) is seated in a closed position on seat (40). A diaphragm actuator (70) has a diaphragm (76). A linkage including opposed link arms (106, 108) is positioned between the diaphragm (76) and the piston valve member (32) and a roller (104) supported on link arms (106, 108) contacts the valve member (32) for controlling the movement of the valve member (32) between open and closed positions. The inner upper ends of link arms (106, 108) are pivotally mounted on bracket (94) secured to the housing and the lower outer ends of the link arms (106, 108) are pivotally mounted on opposed brackets (88, 90) secured to the diaphragm (76). An axial movement of the diaphragm (76) of about two inches results in an axial movement of roller (104) and piston valve member (32) of about 0.20 inch to provide a ratio of about ten to one.