Abstract: A self-configuring photoelectric control circuit for controlling operation of a load based on ambient light. The photocontrol circuit comprises a photocell responsive to ambient light, a heating resistor connected to the photocell, a bimetallic element in proximity to the heating resistor and movable in response to generation of heat from the heating resistor. A switch is operated by the bimetallic element and is connected between an input connected to a power source and an output connected to the load. A series resistor is connected to the heating resistor and a shunt is connected across the series resistor to provide a current bypass around the series resistor for operation with a low voltage power source, for instance 120 volts. The shunt is maintained in a flexed condition to form the bypass and a connection of the shunt across the series resistor is formed of a meltable material.

Abstract: A push button variable resistor device includes a hollow push button seat member confining a receiving space, and at least one resistor piece fixed inside the seat member. The resistor piece has a contact portion and at least one leg portion projecting outward through a base portion of the seat member. A spiral spring resistor is disposed inside the receiving space of the seat member above the resistor piece. The spring resistor has a plurality of concentric turns of varying diameters. A push button is slidably fitted through a button opening of the seat member. The spring resistor hs a topmost turn cooperatively associated with the push button. The push button is externally pushed to compress the spring resistor to cause the concentric turns to contact the resistor piece. The contact area between the spring resistor and the resistor piece varies according to the degree of depression of the push button to correspondingly vary the output resistance of the variable resistor device.

Abstract: Resistive position indicator has an enlongated resistive element with an electrical terminal at each end and a tap which can be brought into contact with the resistive element. A contact point divides the resistive element into two portions and is movable along the resistive element, so that the resistance ratio between the two portions of the resistive element can be varied within wide limits. The resistive element consists of a layer of resistive material applied on a substrate of electrically insulating material. The tap comprises an elongated contact portion of electrically conducting material applied on a substrate and positioned in front of, parallel to, and slightly spaced from the resistive element, so that an air gap is formed between the resistive element and the contact portion of the tap.