Abstract: A device is described for stimulating the auditory transmission branch of the 8th nerve. It uses electrodes designed to restrict the electrical field to the region of their respective nerve fiber group and produce a gradient field for each channel such that the latency characteristics of the nerve fibers in a given channel will cause a sequential firing (streaming) of the nerve fibers during a portion of the channel stimulus pulse. In the analog system the nerve fiber channels are stimulated in sequence but with their stimulus overlapping their previous channel by an amount equal to the shortest latency period of said channel. During the period when a stimulus pulse is causing nerve fiber streaming the pulse amplitude is modulated with the audio information. In addition during the nerve fiber streaming either electrical means or the shape of the probe compensate for the strength-duration characteristics of the individual nerve fibers.

Abstract: A fast response control circuit for providing an output signal in miminum time after receiving an enabling input signal. The control circuit includes an amplifier which provides an output signal having a magnitude determined by a variable input signal when the enabling input signal indicates that an output signal is desired. A feedback network and the amplifier together define a control loop which has a characteristic response time. When the enable signal is absent, a bias control biases a reactive component in the control loop so as to minimize this response time. The circuit is adapted for use in a fluid mass flow controller to provide rapid response to an enabling input signal, particularly when a very low fluid flow rate is desired.

Abstract: A fluid mass flow controller for maintaining the flow of a fluid at a predetermined rate despite fluctuations in inlet fluid pressure. The controller employs a sensor to measure the rate of flow of the fluid downstream from a control valve; negative feedback is generated from the sensor output and is used to regulate the valve setting to maintain a constant flow at the predetermined rate.

Abstract: An automatic equalizer for an electronic measuring instrument using a transducer to measure a physical quantity. A signal amplifier in the instrument has a positive feedback application point and a negative feedback application point. The automatic equalizer has a plurality of stages, each comprising an amplifier that draws its input from the compensated output of the signal amplifier. Each equalizer stage is biased to operate over a different range of output signal levels, and the amount of feedback supplied by each stage back to the positive and negative feedback application points is separately adjustable so as to equalize a different segment of the transducer response curve. The required bias signal level for each equalizer is independent of the response characteristics of the transducer and therefore can be determined solely with reference to the range of magnitudes of the output signal.

Abstract: A self calibrating electronic instrument for measuring a physical quantity. The instrument generates an internal correction signal that forces its output to zero whenever it is determined that no physical quantity is present for measurement. The correction signal so generated is preserved and continuously applied as a correction signal during intervals when measurements are being performed.

Abstract: A mass flow controller is disclosed herein having a bridge with a pair of arms positioned in good heat transfer relation with a gas stream, the flow rate of which is to be controlled and energized by a constant current generator wherein a resistance difference due to differential cooling by the gas stream is sensed by a bridge amplifier. A linearization network receives a signal from the bridge amplifier and applies one or more correction factors to the bridge amplifier signal to yield a linearized signal having a substantially linear relation to the rate of flow of the gas stream. A comparator receives the linearized signal and a user selectable set point signal and produces a comparator output signal which is sensed by a servoamplifier. The servoamplifier controls a valve which meters the rate of flow of the gas stream.