Abstract: A diagnostic circuit is configured for connecting to a unit under test that has a load and a sinusoidal source. The diagnostic circuit includes a voltage sensing device that has an input for sensing a signal, a first terminal for connecting to the load, a second terminal for connecting to the sinusoidal source, and a relay connected between the first and second terminals for connecting the sinusoidal source to the load. Clamping diodes are provide for clamping a sinusoidal signal and include a first clamping diode connected between a D/C voltage source and the input and a second clamping diode connected between ground and the input. A resistor is connected between the D/C voltage source and the first terminal. The diagnostic circuit verifies the operational functionality of the load, related wiring and connections.

Abstract: A diagnostic circuit is configured for connecting to a unit under test that has a load and a sinusoidal source. The diagnostic circuit includes a voltage sensing device that has an input for sensing a signal, a first terminal for connecting to the load, a second terminal for connecting to the sinusoidal source, and a relay connected between the first and second terminals for connecting the sinusoidal source to the load. Clamping diodes are provide for clamping a sinusoidal signal and include a first clamping diode connected between a D/C voltage source and the input and a second clamping diode connected between ground and the input. A resistor is connected between the D/C voltage source and the first terminal. The diagnostic circuit verifies the operational functionality of the load, related wiring and connections.

Abstract: A diagnostic circuit is configured for connecting to a unit under test that has a load and a sinusoidal source. The diagnostic circuit includes a voltage sensing device that has an input for sensing a signal, a first terminal for connecting to the load, a second terminal for connecting to the sinusoidal source, and a relay connected between the first and second terminals for connecting the sinusoidal source to the load. Clamping diodes are provide for clamping a sinusoidal signal and include a first clamping diode connected between a D/C voltage source and the input and a second clamping diode connected between ground and the input. A resistor is connected between the D/C voltage source and the first terminal. The diagnostic circuit verifies the operational functionality of the load, related wiring and connections.

Abstract: A diagnostic circuit is configured for connecting to a unit under test that has a load and a sinusoidal source. The diagnostic circuit includes a voltage sensing device that has an input for sensing a signal, a first terminal for connecting to the load, a second terminal for connecting to the sinusoidal source, and a relay connected between the first and second terminals for connecting the sinusoidal source to the load. Clamping diodes are provide for clamping a sinusoidal signal and include a first clamping diode connected between a D/C voltage source and the input and a second clamping diode connected between ground and the input. A resistor is connected between the D/C voltage source and the first terminal. The diagnostic circuit verifies the operational functionality of the load, related wiring and connections.

Abstract: A diagnostic circuit is configured for connecting to a unit under test that has a load and a sinusoidal source. The diagnostic circuit includes a voltage sensing device that has an input for sensing a signal, a first terminal for connecting to the load, a second terminal for connecting to the sinusoidal source, and a relay connected between the first and second terminals for connecting the sinusoidal source to the load. Clamping diodes are provide for clamping a sinusoidal signal and include a first clamping diode connected between a D/C voltage source and the input and a second clamping diode connected between ground and the input. A resistor is connected between the D/C voltage source and the first terminal. The diagnostic circuit verifies the operational functionality of the load, related wiring and connections.

Abstract: A diagnostic circuit is configured for connecting to a unit under test that has a load and a sinusoidal source. The diagnostic circuit includes a voltage sensing device that has an input for sensing a signal, a first terminal for connecting to the load, a second terminal for connecting to the sinusoidal source, and a relay connected between the first and second terminals for connecting the sinusoidal source to the load. Clamping diodes are provide for clamping a sinusoidal signal and include a first clamping diode connected between a D/C voltage source and the input and a second clamping diode connected between ground and the input. A resistor is connected between the D/C voltage source and the first terminal. The diagnostic circuit verifies the operational functionality of the load, related wiring and connections.

Abstract: A diagnostic circuit is provided. The diagnostic circuit comprises resistors and a capacitor. The diagnostic circuit is monitored to detect the presence of a load and to confirm the proper operation of a relay circuit. The diagnostic circuit generates an oscillating voltage when the relay circuit is open and the load is connected, generates a logic low when the relay circuit is open and the load is disconnected, and generates a logic high when the relay circuit is closed. The diagnostic circuit can be disposed within a diagnostic circuit system that includes one or more of a sensing circuit, a relay circuit, an alternating-current source having a direct current offset, an input circuit, and a high-voltage microprocessor. The high-voltage microprocessor can be bi-directionally optically coupled to an application microprocessor.

Abstract: A spa communication system for establishing a communication link between a central spa box having a control module and spa components in a spa system. The spa control module is connected to the spa components through a communication link, and the spa control module sends command signals to at least one spa component and receives status information from at least one spa component on the communication link.

Abstract: An oven temperature controller for regulating temperature to a temperature setpoint over a temperature range in an oven compartment comprising a microprocessor and memory storage means. The memory storage means stores temperature setpoint related information for temperature setpoints over the temperature range and this information is used by the microprocessor for establishing an upper control limit curve and a lower control limit curve. The upper control limit curve and lower control limit curve have no discontinuities over a majority of the temperature range and at least one of these curves is non-parallel to a temperature setpoint line, the temperature setpoint line formed in a stepwise linear manner between temperature setpoints as the temperature setpoint is varied over the temperature range.

Abstract: A method and apparatus for mounting a controller (30) along with its program selector switch (36) and other electrical components (34) on appliance front panels is disclosed. A twist mount (40) removably mounts a selector switch (36) and printed circuit board (32) to a control panel (20) of an appliance. The switch (36) may be positioned off-center on the printed circuit board (32) in a manner creating a gravity-based rotational torque force on the twist mount (40), such that the printed circuit board (32) acts as a cantilever arm during mounting, and the selector switch (36) is held in the mounted position via the gravity force after mounting.

Abstract: A method and apparatus for operating and executing a self-test routine of an LED display device adapted for assembly into home appliance. The device is comprised of a plurality of LED elements, a control processor, a switch assembly, and a signaling element. The self-test routine comprises disposing the switch assembly in a predetermined pattern for detecting switch operability and initiating a program in the processor for self-testing of illumination of the LED elements. The elements are monitored during the self-test routine for communicating a minimum current level preselected as identifying proper illumination. Failure of the self-test routine to properly detect minimum current levels precludes a proper response from the signaling element within a predetermined time limit, thereby causing the display device to be identified as an unacceptable device.

Abstract: In an appliance such as an oven for cooking food, the invention contemplates a user rotatable, single knob oven control device which provides both discrete and continuous control signals to the appliance controller. The discrete outputs indicate selection of oven features, and the continuous output the desired baking temperature. These inputs are selected by a user in response to rotation of a user interface knob mounted on a control panel. The control panel provides visual indication of oven cooking temperature selections through a first arc around the knob, and user selectable oven features (such as, e.g., OFF/CANCEL, BROIL, and CLEAN) in a second arc around the knob. The control device comprises a hub having a portion adapted to be drivably coupled to the user interface knob. The hub also includes a flange which has at least one cam. The device also includes a variable resistance element having a rotatable shaft in driving engagement with the hub.

Abstract: A method and apparatus for operating and executing a self-test routine of an LED display device adapted for assembly into home appliance. The device is comprised of a plurality of LED elements, a control processor, a switch assembly, and a signaling element. The self-test routine comprises disposing the switch assembly in a predetermined pattern for detecting switch operability and initiating a program in the processor for self-testing of illumination of the LED elements. The elements are monitored during the self-test routine for communicating a minimum current level preselected as identifying proper illumination. Failure of the self-test routine to properly detect minimum current levels precludes a proper response from the signaling element within a predetermined time limit, thereby causing the display device to be identified as an unacceptable device.

Abstract: A control system for a dishwasher (10) utilizing a turbidity sensor (24) to achieve an optimum fill cycle water level in a sealable chamber (12) into which soiled dishes are loaded. An electronically actuable fill valve (20) is controlled by a microprocessor (22) in response to signals received from the sensor (24) indicative of the turbidity of water in the chamber (12) during the fill cycle. Once turbidity of the water in the chamber stabilizes or drops to a predefined level, the fill water is determined to have reached an optimum level and the flow of supply water is shut off.

Abstract: A rotary encoded switch having a plurality of stationary discrete micro switches operated by a rotor having a plurality of concentric cam tracks. The cam tracks and switches are disposed such that for each rotary position of the rotor at least two switches, on opposite sides of the rotor are actuated and a discrete combination of switches is actuated for each position of the rotor. The number of microswitches required is less than half the number of rotary positions.

Abstract: A triac-based electronic control system (20) for an electrical appliance which alternately applies and disrupts power in full cycles or full half cycles. Each zero crossing in a wave cycle is detected and this information is input into a microprocessor (U1) along with a user selected power level. The microprocessor outputs a triac control signal (36) to alternately turn ON and turn OFF power to a heater element (22) to produce a duty cycle used to achieve the desired heating level.

Abstract: A monostable, that is triggered by either positive or negative polarity horizontal sync pulses, supplies the horizontal deflection system of a monitor. A first transistor of the monostable has its emitter and its base connected through oppositely poled diodes to the horizontal sync input terminal of the monitor. Incoming horizontal sync pulses of either polarity trigger a respective one of the diodes to drive the first transistor into conduction. The time constant of the first transistor is selected to be slightly greater than the duration of the input sync pulses to preclude the monostable triggering on the trailing edge of a sync pulse.

Abstract: An astable multivibrator that has an integrating network coupled from the output of one of the transistors for developing an operating potential. The operating potential is coupled to the RC timing networks that interconnect the two transistors such that when the transistors are switched by a horizontal sync pulse, the duty cycle is compensated.

Abstract: In the horizontal drive of a raster scanned video display, a free running astable multivibrator responsive to a synchronization input signal provides a horizontal output signal to horizontal deflection circuitry for synchronizing the video display's raster scan with the video information presented thereon. The astable multivibrator includes a pair of coupled transistors which are alternately rendered conductive in accordance with the time constant of a respective RC network associated with each transistor. To compensate for the temperature-dependent operation of the transistor pair which causes the multivibrator's operating frequency to increase with increasing temperature, a pair of back-to-back coupled diodes are connected to provide the synchronization input signal to one RC network so as to increase the charge on a capacitor within the network, the time constant of which is similarly increased. The temperature-dependent change in voltage across the diodes compensates for the change in V.sub.

Abstract: Disclosed is a power supply having transformer isolation which is capable of providing a plurality of precisely regulated output voltage levels. This regulated power supply is particularly adapted for use in a video display terminal because the output voltages may be scan-derived for improved video presentation with a plurality of precise voltage levels for driving various terminal logic levels provided by a single DC signal source.