Abstract: A multiple heater control system includes cables, connectors, and junction boxes for user-friendly daisy chain connections of heater controllers and heaters in various configurations or combinations of individually controlled heater series and/or master and slave heater series. The heater controllers include process control of AC power to the heaters and upper-limit safety shutoff that is substantially independent from the process control. The heater controllers also have variable levels of control, adjustment, display, and communications functionality in a base module that is expandable to various levels with expansion modules that are attachable to and detachable from the base module. Connector, cable, and junction configurations, adapters, and latch features enhance user friendliness.

Abstract: A user interface assembly for a power controller has a housing is adapted for mechanically coupling to a controller housing of the power controller in a releasable manner, a display visible on an outer surface of the housing for providing a visual presentation to a user, and a user input mechanism for receiving an input from the user. A user interface circuit is disposed within the housing and coupled to the display and the user input mechanism for controlling an operation the power controller when coupled to the user interface assembly. A connector is coupled to the user interface circuit and adapted for electrically connecting the user interface circuit to an electrical connector associated with the power controller upon the mechanical coupling of the housing to the controller housing and electrically disconnecting upon mechanical decoupling of the housing from the controller housing.

Abstract: A power control system has a controller housing, a power switch disposed within the controller housing for selectively providing power from a power supply to a power load, a limiter disposed within the controller housing configured for providing a limit switching function in response to a threshold limit, and a controller disposed within the controller housing and configured for controlling one or more operations of the control system.

Abstract: A laser based accelerometer system uses small motion induced shifts in frequency to measure the motion of an object without contact thereof. This technique is particularly useful for determining the vibratory and velocity characteristics of objects that are otherwise inaccessible for direct motion measurement by contact sensors.

Abstract: A directional antenna system is disclosed which selectively couples two radiating antenna elements to a transceiver through a selective phase, magnitude and matching network which is controlled by the output of a logic circuit. The network provides for equal magnitude current coupling between the transceiver and the two antennas while simultaneously selectively producing either positive or negative approximately 90.degree. phase shifts between the two antennas to produce either of two discrete directive cardioid radiation patterns directed in substantially opposite directions. The logic circuit, in conjunction with a manual step switch, provides for a manually selecting either of the two cardioid radiation patterns, as well as producing a figure eight or an omnidirectional radiation pattern. For generating a transceiver omnidirectional pattern, one antenna is used and the other is connected to a standard broadcast band receiver.

Abstract: A system for detecting the presence of coherent radiation comprises an interference filter having a pair of partially-reflective mirrors. The spacing between the mirrors is varied in accordance with a sine function to change the transmission wavelength of the mirrors. A reference signal is developed which represents this periodic variation in the spacing of the mirrors. A photodetector on the output side of the filter detects radiation transmitted therethrough, yielding a detection signal in the presence of coherent radiation transmitted through the filter. An indicator responds to the signal output of the photodetector and to the reference signal to produce an identifying indication of the detected radiation.