Abstract: A doorbell circuit detects when one of a plurality of doorbell switches is depressed and provides an audible indication of the particular doorbell switch depressed. The doorbell circuit includes a detector circuit which will function properly with the diode, normally connected in parallel across one of the doorbell switches, connected with either polarity. A power supply is developed for the detector circuit from the doorbell transformer by way of the diode connected in parallel across one of the doorbell switches. The detector circuit includes one or more full-wave rectifiers, which provide a positive DC output signal irrespective of the polarity of the diode connected in parallel across the doorbell switch. Each of the doorbell switches is connected to an amplifier, which, in turn, is connected to a comparator.

Abstract: A wireless multiple position switching system is disclosed for controlling the application of power to a load device from a plurality of remote locations. The switching system includes a power source, a load device, a master toggle switch and one or more slave toggle switches. A slave toggle switch generates an electromagnetic switching signal which changes the state of the master switch. The master switch is connected in series with the power source and the load device and controls the application of power to the load device in response to the switching signal from the slave switch or actuation of its own toggle.

Abstract: A security light has a quartz-halogen lamp, a photocell, a passive infrared sensor for detecting motion external to the security light, and a circuit which causes the quartz-halogen lamp to operate at about 50% of full brightness in the absence of detection of motion at night, to operate at 95% of full brightness for a predetermined time interval in response to detection of motion at night, and to be off while the photocell is detecting daylight. A switch allows the user to select a different mode of operation which is similar except that the lamp is kept off in the absence of detection of motion at night. A user-initiated override mode is also provided, which causes the lamp to continuously operate at 95% of full brightness until the photocell detects daylight or until the user disables the override mode.

Abstract: A motion detector housing assembly is adapted to be integrated into a decorative coach lamp. The motion detector housing assembly includes a motion detector housing and a carrier assembly which may be configured in a manner to be similar to a decorative housing normally disposed on the top or bottom of the coach lamp assembly. The motion detector housing may be formed with upper and lower housing portions; together which form a generally frustro-conical configuration to match the configuration of a decorative housing disposed on the top or bottom of a lamp assembly. The lower housing portion is formed with an annular window. An important aspect of the invention is that the Fresnel lens member is configured in a generally cylindrical shape. As such, the optics of the system are improved and, in addition, decouples the lens design from the design of the lower housing portion. In order to protect the lens member a plastic lens cover is provided.

Abstract: A DC power supply for an electronic switching element connected in series with a load in an AC main has a rectifying element and a capacitor parallel to the electronic switching element. Charging of the capacitor is provided by opening the switching element and diverting current from the AC main through the rectifying element and capacitor. The voltage difference across the capacitor powers control circuitry for the electronic switching element. Hysteresis built into the control circuitry results in the electronic switching element opening at a lower voltage difference across the capacitor than the voltage difference required to close the electronic switching element.

Abstract: A security light has a quartz-halogen lamp, a photocell, a passive infrared sensor for detecting motion external to the security light, and a circuit which causes the quartz-halogen lamp to operate at about 50% of full brightness in the absence of detection of motion at night, to operate at 95% of full brightness for a predetermined time interval in response to detection of motion at night, and to be off while the photocell is detecting daylight. A switch allows the user to select a different mode of operation which is similar except that the lamp is kept off in the absence of detection of motion at night. A user-initiated override mode is also provided, which causes the lamp to continuously operate at 95% of full brightness until the photocell detects daylight or until the user disables the override mode.

Abstract: A wireless multiple position switching system is disclosed for controlling the application of power to a load device from a plurality of remote locations. The switching system includes a power source, a load device, a master toggle switch and one or more slave toggle switches. A slave toggle switch generates an electromagnetic switching signal which changes the state of the master switch. The master switch is connected in series with the power source and the load device and controls the application of power to the load device in response to the switching signal from the slave switch or actuation of its own toggle.

Abstract: A wireless multiple position switching system is disclosed for controlling the application of power to a load device from a plurality of remote locations. The switching system includes a power source, a load device, a master toggle switch and one or more slave toggle switches. A slave toggle switch generates an electromagnetic switching signal which changes the state of the master switch. The master switch is connected in series with the power source and the load device and controls the application of power to the load device in response to the switching signal from the slave switch or actuation of its own toggle.

Abstract: A universally movable electrical fixture having a ball carrying base and cooperating electrical fitting carried socket with a unique tab projection that rides in a circumferential slot in the ball shaped to permit free swinging movement of the electrical fixture while limiting the rotational movement of the fixture to about 130 degrees to minimize electrical conductor twisting.

Abstract: An opto/acoustic navigation system allows a mobile robot to detect and mate with a floating plug-equipped charging unit upon detection of the need for recharging of the robot's storage battery. A plurality of infrared (IR) emitters and sensors located on the robot and adjacent to the charger in combination with the robot's acoustic sensors allow the robot to locate the charger, move to within a predetermined distance of the charger, maneuver to a position directly in front of the charger, and then back into engagement with the charger's floating plug.

Abstract: A microphone is provided with a read only memory (ROM) which is programmed to compensate for the microphone's nonlinear frequency response characteristic during their integration into a single unit. The ROM is thus programmed to provide a frequency response complementary to that exhibited by the microphone. The microphone may have a relatively poor frequency response over the audio spectrum, i.e., 20 Hz-20 kHz, but with the ROM serving to calibrate the microphone, the combination exhibits a relatively flat frequency response over this frequency range. Intended for use in a portable, battery operated, microprocessor-controlled audio spectrum analyzer, the integrated microphone and ROM combination is coupled to a CMOS random access memory (RAM) in which the calibration contents of the ROM are stored. During normal operation, the microprocessor reads the microphone calibration data from the thus programmed RAM in order to conserve battery power, but may read this data from the ROM when necessary.

Abstract: A sonar ranging/light detection system provides information regarding the surrounding environment to a robot. The sonar portion of the system includes an upper rotating detector which provides 360.degree. coverage as well as a lower, fixed detector located on the front of the robot which provides sensory information in the direction of robot movement. A light detector similarly provides a 360.degree. light sensing capability. The upper sonar and light detectors utilize a common rotating mirror driven by a stepper motor and include a slotted shaft encoder in combination with an optopair semiconductor detector. The shaft encoder provides angular information to a microcomputer controller which is also responsive to sonar ranging information in exercising control of the stepper motor. The transmitted sonar signal is comprised of a pulse train of four different frequencies to ensure that simultaneous echoes from more than one surface do not cancel each other out and provide false ranging information.

Abstract: A real-time, microprocessor-controlled, 1/2-octave audio spectrum analyzer is capable of operating in a difference mode wherein a current input may be compared with a previously stored input and the difference therebetween directly displayed in real time. A reference response may be displayed and stored in memory for later comparison with another audio signal for which a spectrum analysis is desired. For example, if an output from a pink noise generator is stored as the reference spectrum and the output from a speaker is the audio signal to be measured, the difference mode of operation will subtract the frequency response of the speaker from that of the noise generator and display the difference. Thus, it is not necessary to take into account frequency response errors of the reference signal source in making highly accurate spectral comparisons.

Abstract: A gripper assembly for a robotic arm includes two opposing elements displaced by means of a worm gear arrangement for grasping an object positioned therebetween. The worm gear is driven by a rotary drive motor with a torsion spring coupling the drive motor shaft to the worm. First and second shaft encoders are respectively mounted to the drive motor shaft and the worm shaft. First and second pairs of optical sensors respectively coupled to the first and second shaft encoders detect the angular speed and displacement of the drive motor shaft and the worm. With the torsion constant of the spring known, the force applied by the gripper assembly which is proportional to the angular displacement of the worm may be accurately determined and controlled. In addition, the size of the object grasped by the gripper assembly may be determined. By comparing these operating parameters with selected values, the gripper assembly may be precisely controlled such as by means of a microcomputer.

Abstract: Time referenced RF signals are periodically received and processed for updating a microprocessor-controlled clock. The clock automatically scans several frequencies at which the coded RF timing signals are transmitted, selecting the strongest received signal for synchronization therewith and causes a capture LED to be illuminated upon detection of a sufficiently strong signal at the beginning of a minute tone at one of the received frequencies. The microprocessor periodically determines the timing difference between an internal timer and the received RF timing signals. A time difference correction is provided to a digital-to-analog converter which provides an appropriate voltage to a varactor diode in a crystal oscillator circuit for adjusting the microprocessor's operating frequency until it can no longer resolve a difference between the received RF timing signals and its internal timer.

Abstract: A system and method for displaying graphic information and comparing this information with reference data on the faceplate of a cathode ray tube (CRT) is disclosed. The graphic information is provided via a first channel and the reference data is provided via a second channel to a multiplexer for the alternating, sequential display of the graphic information and reference data on the CRT. A high frequency oscillator in combination with logic circuitry provides on/off modulation of one of these inputs to the CRT to produce an interrupted, discontinuous display of the thus modulated signal. One set of data is thus displayed as a continuous line, while the other set of data is presented in dotted line form. The present invention is particularly adapted for the presentation of two sets of closely matched data points on a CRT to facilitate the differentiation and identification of each data set.