Abstract: A modular plug connector is adapted to terminate a cord having a number of insulated solid wire conductors. The connector includes a dielectric housing that facilitates interconnection between the solid wire conductor and a metallic terminal which slides into a terminal-receiving slot of the dielectric housing. The metallic terminal includes three tangs, or blades, that pierce the insulation surrounding the solid wire and achieve electrical contact. Adjacent tangs grasp the solid wire on opposite sides of its center line, but are controllably spread before making contact with the wire by cam surfaces molded into the side walls of the terminal-receiving slot. Reliable connections are therefore made between a metallic terminal and a solid wire conductor without severing it.

Abstract: An apparatus for detecting the forced opening of a door. The apparatus comprises a paper sheet with a frangible conductive path thereon. The sheet has holes therein for the passage of a retractable bolt and fasteners, which are used to secure a strike plate to a frame. The sheet is then concealed behind the strike plate and the conductive loop surrounds the fastener holes. When the door is forced open without retraction of the bolt, a crack appears on the surface of the frame surrounding the fasteners. This crack causes a break in the conductive loop. This break is then detected by a detecting device electrically connected to a part of the loop, thereby triggering an alarm.

Abstract: In an electrical circuit where power supply interruptions may cause significant adverse consequences, a secondary battery is often used to maintain power when the load voltage falls below a predetermined threshold. MOS transistors interconnect primary and secondary voltage supplies with the load. A sequence control circuit assures that only one MOS transistor is on at any time. In one embodiment of the invention, different time constants cause all MOS transistors to turn off before changing voltage supplies. In another embodiment of the invention, voltage comparators, each having a different threshold, cause all MOS transistors to turn off before changing voltage supplies. A capacitor maintains the load voltage during switching and positive feedback assures that the switching interval is brief. This arrangement is particularly advantageous in low power applications utilizing one or more lithium batteries.

Abstract: Apparatus and method are disclosed for selecting colors for presentation in a display device such as a CRT. The apparatus includes a pair of video memories that store picture element (pixel) data for presentation at the same location of the display device. A color map, or video look-up table, stores digitally encoded colors that are provided at its output in response to a digital input address. The digital input address is partioned into several portions. Pixel data from the first video memory supplies one portion of the digital input address while pixel data from the second video memory supplies another. Neither video memory has priority in selecting the color presented on the video display although the color map is programmable to give effective priority to either one.The digital address is further partioned into a third portion to thereby define the color map as a plurality of segments.

Abstract: A method is disclosed for distributing processing resources among a plurality of users of a time-shared system wherein resources are divided among various user accounts; each user assigning specific weights to the various programs (processes) in his account. A program is selected for processing in accordance with its assigned weight, the resources allocated to the account containing the process, and its recent processing rate. Programs are executed through a series of processing intervals; after each interval the priority of the executing program is lowered in proportion to the resources consumed. Priorities are recalculated after each processing interval for all programs competing for access to the resources.

Abstract: A Differential Phase Shift Keyed (DPSK) receiver is arranged to detect DPSK signals that contain the O.degree. vector as an information bearing signal in its constellation. The received signal is phase shifted by 90.degree.. A 45.degree. phase shifted signal is thereafter synthesized by additively combining the DPSK signal and the 90.degree. phase shifted signal. Using these signals, detection proceeds by means of correlation techniques. The polarities of the correlation products uniquely determine the phase changes of the DPSK signal.

Abstract: A class of product demodulators operates by multiplying an input signal with a delayed version of itself. Bias distortion in such product demodulators arises when the signals to be multiplied together are not separated by the correct amount of delay. The amount of delay may be adjusted by additively combining a portion of the incoming signal with the delayed signal. In one embodiment an analog implementation is disclosed having a linear multiplier, adder, and delay line. In another embodiment a digital signal processor is utilized to perform product demodulation in accordance with the invention when periodic samples of the incoming waveform are the available signal.

Abstract: The terminals in the frequency division multiplexed systems of the prior art employ many steps of modulation whose frequency variations, due to changes in the frequencies generated by the carrier oscillators, add to produce a frequency offset which is unacceptable in modern wideband systems. The terminals of the present invention use additional modulators connected to the carrier oscillators to reduce the frequency offset of the transmitted signal to the frequency variations of only a single oscillator.