Abstract: A direct replacement unit for an elevator touch button of the type which uses a voltage dropping gas tube. The replacement unit includes a series circuit, containing a relay coil, a zener diode, an indicator lamp, and a parallel circuit. The parallel circuit includes a normally open contact switch controlled by the relay coil and a mechanical call button.

Abstract: Circuits are disclosed for use in a gaseous-discharge lamp lighting system which provide starting pulses to the lamp and/or a source of auxiliary light. One circuit provides starting pulses and/or auxiliary light until the gaseous-discharge lamp approaches its normal operating condition, while other circuits terminate these functions once the gaseous-discharge lamp ignites.

Abstract: An electronic flash apparatus is provided with a display element positioned in the view-finder of a photographic camera so that the operator is immediately aware if the flash tube has been fired in response to the closure of the synchronous switch. The light emitting operation of this display element is controlled by use of a signal generator arranged to be responsive to the occurrence of discharge through the flash tube of the flash apparatus. With this apparatus, therefore, the operator may rely upon the appearance of this display element to insure that the firing is effected by the flash apparatus even when the object-to-camera distance is relatively small.

Abstract: A neon tube flashing device having a neon tube which emits light upon application of a predetermined voltage thereto to effect indication of operational conditions comprises a capacitor parallel-connected to the neon tube, and switch means series-connected to the capacitor and parallel-connected to the neon tube. The neon tube may be caused to effect flashing by charging-discharging of the capacitor during conduction of the switch means.

Abstract: Gaseous discharge lamp is connected to a current sensing transformer which generates a signal when the lamp is on to turn on a triac operating a relay for turning off an auxiliary incandescent lamp which automatically operates when the gaseous discharge lamp is extinguished. A time delay circuit including a temperature-sensitive resistor is connected to the triac for keeping the auxiliary lamp in operation until the gaseous discharge lamp reaches a suitable light level.

Abstract: This invention pertains to an emergency lighting circuit that operates with a high pressure, gaseous-discharge lamp and associated ballast. When the gaseous-discharge lamp goes out, after once being ignited, sufficient current is supplied to an incandescent light or lights to maintain illumination to the area normally illuminated by the lamp. The device for providing this current may vary, but generally incorporates a voltage breakdown means that receives higher voltage from the ballast when there is failure of the gaseous-discharge lamp than when the arc therein is struck. A preferred embodiment also lights the incandescent lights during initial warm-up of the gaseous-discharge lamp. The incandescent lights may also be used in a cold environment to maintain the gaseous-discharge lamp sufficiently above an ambient temperature level to make possible initial striking of the arc in the lamp when ambient temperature conditions might otherwise prevent it.

Abstract: Voltage indication means for an electronic flashing device in which a low D.C. voltage is converted to a high D.C. voltage by a DC-DC converter circuit and energy stored in a main discharging capacitor is supplied to a flashing discharge tube to fire it, wherein the charged voltage of the main discharge capacitor is indicated by utilizing the fact that the charged voltage of the main capacitor is in equivalent relation with a voltage generated in the DC-DC converter.

Abstract: An electronic flash unit having the conventional flash tube, storage capacitor dischargeable through the flash tube, measuring device for recording the quantity of light emitted by the flash tube and reflected back from the subject being photographed, a pulse generator responsive to the measured reflected light, and means for quenching the flash in response to a pulse produced when the measured reflected light reaches a threshold value. The present flash unit, in addition to the conventional features just mentioned, includes the novel feature of a light-emitting diode which becomes illuminated when the light measuring means and the pulse generator circuit become operative, thus signalling to the user of the device that the so-called "computer" mechanism has actually operated. Circuit means is provided for extinguishing the light-emitting diode at the proper time.

Abstract: An internally illuminated switch plate for providing visual indications of the on-off condition of an electrical wall switch. The plate comprises a wall plate in the form of a flat slab adapted to overlie the wall fixture and constituted of material which conducts light. A small recess in the rear surface carries a neon glow lamp, and a second recess carries a resistor. The glow lamp and resistor are connected in series, and this assemblage in turn connected across the terminals of the switch. Connections to the neon lamp and resistor are made via tracks of conductive paint disposed in grooves in the rear surface of the slab. The tracks extend to two terminals of the slab, from which flexible leads are run to terminals of the switch. The arrangement is such that when the switch is off, the lamp is energized by the voltage normally appearing across the switch terminals, to thus provide a visual indication of the on-off condition of the switch.

Abstract: An emergency lighting system, employing a mercury lamp and an incandescent lamp, and relay circuits for turning on the incandescent lamp in substitution for the mercury lamp, when the light output of the latter is limited, during either cold start or hot start, and for turning off the incandescent lamp without chatter.

Abstract: Failure inducive operating conditions of an X-ray generator tube are sensed. Some of the sensed operating conditions are events such as hot overload of the target and thermal shock of the target, while other sensed operating conditions include hot target bearing use and thermionic cathode filament heater use. Certain of the sensed operating conditions are integrated, with the integrated output being compared against a predetermined standard to yield a prediction of remaining operating life. Other sensed conditions, if present, are indicative of incipient failure without integration. The integrated signals are stored in electrochemical cells and read out periodically for a prediction of incipient tube failure.