A solid state amplifier includes at least one junction field effect transistor and an impedance network coupled between a signal input terminal of the amplifier and a gate terminal of the transistor. The network includes a p-n junction device having a region of conductivity opposite to that of the gate of the transistor coupled to the gate terminal, the p-n junction being shunted by a resistor coupled in parallel therewith. The network minimizes signal distortion which would otherwise be introdu...

State detecting apparatus comprising: first, second and third terminals, first and second potential detecting circuits each having an input and an output, a resistance, means connecting the inputs of the first and second potential detecting circuits to the first terminal, means connecting the resistance between the first terminal and a power source, means connecting the output of the first potential detecting circuit to the second terminal, means connecting the output of the second potential det...

A solid state switch particularly useful in assisting in the starting of permanent split capacitor (PSC) motors is disclosed in which a semiconductive element is used to affect the starting torque of the motor. The semiconductive element is a disk-shaped member composed of material having a relatively low resistance at temperatures below an anomaly point and a steeply sloped positive temperature coefficient (PTC) of resistivity at temperatures above the anomaly. The PTC element is mounted within...

Apparatus for evaluation a human subject's color vision response including light emmiting diodes providing luminance in the yellow and red and green color spectrums, means for controlling the individual luminescence of the red and green diodes in an inverse relationship and means for displaying the yellow and red-green luminescence for comparative viewing by the human subject.

A wristwatch has a plurality of light emitting digital readout elements which are located along one end of the watch above the watchband. A hermetically sealed time capsule is enclosed within the watch case and includes an integrated circuit chip which divides the frequency output of a battery powered quartz crystal oscillator into a series of pulses which are counted and selectively interrogated to provide a series of electrical outputs corresponding to seconds, minutes, hours, days, months and...

A solid state depth sounding system, for measuring depth and detecting the presence of underwater objects, comprises an oscillator, producing high frequency electrical signals, a transmitter, for intermittently amplifying those signals, a transducer, and a receiver. The transducer produces high frequency sound impulses from the intermittent amplified signals, and transmits those impulses through the water until they are reflected by some underwater object. The transducer also picks up the reflec...

A solid state electrical switch of versatile and economical structure for use in starting a split-phase electrical motor incorporates a single cup-shaped dielectric casing open at one end. A first terminal disposed within the casing has integral spring portions bearing against the casing bottom and has a connector portion extending through the casing wall to receive connection from the starting winding of such a motor. A ceramic-type resistor element of positive temperature coefficient of resist...

A viscosimeter is provided using a piezoelectric transformer to provide vibratory energy thereby imparting shear waves to the surrounding fluid. An output signal provides a representation of the fluid viscosity.

A solid state timing and cycling device utilizing integrated circuits and other discrete solid state components to control the operation of electrically actuated remote control valves for the purpose of automatically programming the operation of all types of systems designed to distribute water for irrigation, spraying, and humidification of plant materials. The control comprises six sections including a digital readout clock circuit, a calendar circuit, an hours memory circuit, a station output...

A solid state crosspoint switch particularly suited for use in a telephone switching matrix includes two switching transistors. Audio signals are enabled to pass through the crosspoint switch via a low impedance path by driving the two switching transistors into saturation from a gated control circuit responsive to appropriate control signals. Noise immunity is provided by a current regulating switch interposed between the crosspoint switch and the control circuit. Another embodiment includes tw...