Abstract: An electronic musical instrument by which a performer can provide a musical accompaniment in different musical styles. The performer selects a desired musical style and plays on a standard keyboard in order to express a desired harmony. The instrument translates the keyboard playing into a chord type and root that defines the harmony expressed by the performer. A processor generates parameter signals defining a segment of music including a plurality of accompaniment notes arranged in the selected musical style and related harmonically to the selected chord type and root. Output circuitry converts the parameter signals to sound so that a performer of limited skill or musical knowledge can play an appropriately-styled accompaniment to a melody written in any one of a variety of musical keys.

Abstract: An opacity monitor (10) including a light source (12) mounted on one side of a duct (14), and a detector (16) mounted on the opposite side of the duct is disclosed. The light source (12) and the detector (16) are rotated by motor means (26, 36), respectively, between a first position aligned with each other along an open light path defined across the duct (14) and a second position aligned with each other on opposite sides of a calibration tube (18) extending across the duct (14). Shutters (28, 38) rotate with the light source (12) and the detector (16), respectively, and are aligned with the calibration tube (18) when the light source (12) and the detector (16) are aligned with the open light path, and vice versa.

Abstract: Apparatus for controlling the duty cycle of a rectangular input signal so that the duty cycle normally remains constant irrespective of the frequency of the input signal, but can be adjusted with accuracy. A generator initiates a rectangular output signal in synchronism with the input signal. A comparator enables the generator to terminate the output signal after a time period related to the relative amplitudes of the output signal and another reference voltage. An adjustment transistor can adjust the amplitude of the reference voltage in order to control the overall duty cycle of the output signal.

Abstract: Techniques for translating the harmony expressed by the keyboard playing of a performer into a chord type and root. Playing key pattern representations are stored in a digital memory at locations having addresses defining the corresponding chord type. A playing key pattern signal identifying the pattern of the keys played by the performer is then generated. The playing key pattern signal is used to locate the corresponding stored playing key pattern representation. When a match occurs, the chord type and root are derived by a processor.

Abstract: Disclosed is a lost motion coupling for connecting a propulsion device with a load to be moved. The coupling permits the propulsion device to generate significant momentum before applying driving force to the load. In the embodiment described, a traveling nut is driven in translational motion along a rotatable screw. The traveling nut is included within the lost motion coupling between the screw and a slide gate. Significant rotational momentum may be obtained by the screw before the lost motion coupling applies driving force to the slide gate. The slide gate then experiences an abrupt application of a substantial driving force to overcome forces retarding motion of the slide gate.

Abstract: A pressure sensitive Silicon chip is indirectly bonded to a Stainless Steel housing of an electronic pressure transmitter through an intermediate holder assembly. This indirect bonding prevents thermal cracking of the Silicon chip due to the difference in thermal expansion of the Stainless Steel housing and the Silicon chip. The holder assembly includes a Borosilicate glass tube having the Silicon chip bonded thereto which tube is soldered to a Nickel-Iron alloy holder by a eutectic alloy solder. In assembly, the Nickel-Iron holder is first brazed to the stainless Steel housing at a first temperature greater than the maximum non-destructive temperature of either the chip or the glass tube and the glass tube is then soldered to the Nickel-Iron holder at a lower temperature which will not destroy the chip or the tube holder.