Abstract: A surround audio system for a vehicle with a plurality of operating modes. The vehicle includes seating locations. The audio system includes a plurality of input channels including surround channels. The audio system further includes a plurality of operating modes. A first operating mode is characterized by substantially equal perceived loudnesses at each of said seating locations, an equalization pattern developed by weighting frequency responses at each of said seating locations substantially equally, and a balance pattern developed by weighting sound pressure level measurements at each of said seating locations substantially equally.

Abstract: A vehicle sound system is constructed and arranged to establish a sound image at a desired location spaced from the sound source.

Abstract: A dielectric resonator system having a dielectric element and a purified alumina attachment assembly both housed within a metallic resonant casing. Attachment assembly is at least 99.5% pure alumina. Attachment assembly couples dielectric element to the casing. Dielectric element is an internally threaded ring or disk. Attachment assembly includes an externally threaded alumina support member coupled to the internally threaded dielectric element.

Abstract: A dual temperature hair curler has a hollow heat transmitting metallic barrel enclosing a pair of PTC heaters connected in series to each other and electrically insulated from the barrel by an oxide-filled silicone rubber material. The PTC heaters have different anomaly temperatures and a switch arrangement is provided for (1) energizing the higher anomaly temperature heater a series with the lower anomaly temperature heater to produce a low temperature limited by the anomaly temperature of the lower temperature heater and (2) effectively energizing only the higher anomaly temperature heater to produce a high temperature limited by the anomaly temperature of the higher temperature of the higher temperature heater by bypassing the lower anomaly temperature heater.

Abstract: A heating device adapted to be disposed in an opening in the side wall of a compressor that is used with an air conditioner or refrigerator so that fluids in the casing of the compressor can be vaporized. The heating device includes a PTC thermistor disposed in a housing and a generally cylindrical receptacle disposed about the housing. The housing includes at least one outwardly extending, resilient, heat dissipating, arcuate fin overlying the outer surface of the housing in spaced relaton thereto. The fin is biased outwardly to engage the inner walls of a receptacle. The receptacle is welded into the opening in the sidewall of the casing of the compressor. The fins form a snug fit with the housing and provide a good heat transfer contact with the receptacle. Lead-in wires extend from the PTC thermistor to the outside of the housing so that the PTC thermistor can be connected to a power supply.

Abstract: A PTC motor starting device is disclosed including a PTC resistor body having a pair of electrodes disposed on the PTC body and a lead terminal extending outwardly from each of the electrodes. A heat sink material is disposed about the PTC resistor body to absorb the heat generated by the PTC resistor body to reduce the temperature of the PTC resistor body to a temperature below the anomalous or reset temperature. A casing is disposed about the heat sink material.

Abstract: A heater adapted to be disposed in a vessel whereby to heat liquids contained therein. The heater includes a sealed heat-transmitting cannister that is adapted to be immersed in a vessel containing a liquid media. A foraminous PTC thermistor is disposed in the cannister and electrically insulated therefrom. The thermistor is supported in the cannister by a pair of braces resting upon the inside wall surface of the cannister and each brace includes a pair of facing channels engaging the edges of the thermistor. Electrical connections are provided to convey current to opposite sides of said PTC thermistor. A quantity of electrically inert vaporizable fluid of a predetermined boiling point partially fills the cannister to a level covering the thermistor whereby when current is passed to opposite sides of said PTC thermistor, the fluid will boil and then condense upon the walls of the cannister and give up its latent heat of vaporization and radiate heat into said vessel.

Abstract: An improved diesel fuel heater wherein a predetermined quantity of fuel is captured within the heater in a reservoir defined therein. This quantity is heated by the heater's positive temperature coefficient (PTC) thermistors (and heat conductive mounting plate) to assure a heated quantity of fuel will be pumped into the fuel system's filter element to enhance de-waxing thereof.

Abstract: A frequency responsive power control system includes an improved isolator in series electrical connection with respect to a ballasted lamp load. The isolator has a high inductive impedance at low current for blocking ballast induced noise signals from interferring with proper operation of frequency responsive switching circuits in the system. In a particularly useful embodiment, the isolator is inductively matched to the capacitive characteristic of the ballasted lamp load so that the isolator-load circuit combination is resonant at a frequency sufficiently removed from any of the control system activation frequencies so as to block any noise signals induced by the ballasted load which might otherwise cause undesired activation of the switching circuits and flickering of the ballasted lamp loads. Under saturation current, with the switching circuit conducting, the isolator functions collectively with the load to provide an impedance which blocks control signals from reaching the load.