Abstract: A horn or other vehicle device can be activated or controlled by attenuating light. A horn switch, or an optical switch, has a light source, light detector, and a pathway for light extending through a void. The switches are activated by attenuating the light emitted by the light source. The light can be attenuated by at least partially obstructing the light or by modifying the orientation of either the light detector or the light source.

Abstract: In an intrusion detection system of the kind which comprises a “leaky cable” or open transmission line and is used to determine the presence of objects, things or people moving in the vicinity of the leaky cable, a transmitting antenna and a receiving antenna, one of which is an open transmission line/leaky cable, are connected to a transmitter unit and a receiver unit, respectively. A control unit controls both the transmitter unit and the receiver unit, and causes the receiver unit to scan a preselected radio band, with the transmitter unit not transmitting, to detect one or more relatively quiet portions of the band in which instant received signal levels are lower than a predetermined threshold. The control unit selects a plurality of disparate frequencies in such one or more relatively quiet portions and subsequently causes the transmitter unit to transmit signals by way of the transmitting antenna at the disparate frequencies.

Abstract: The invention provides apparatus and methods for detecting electromagnetic energy using an array of detectors arranged in at least one row and multiple columns. A single crystal body has multiple doped regions disposed therein. Each one of the detectors produces charge in a corresponding one of the doped regions in the body in response to electromagnetic energy impinging upon that detector. A first charge transfer device includes an output port and multiple serially coupled charge storage cells including multiple first charge transfer regions disposed in the body parallel to the row, or rows, of detectors. Multiple second charge transfer devices include multiple second charge transfer regions disposed in the body transverse to the row, or rows, of detectors and the charge storage cells. Each one of the second charge transfer regions is adapted to transfer charge produced in a corresponding one of the doped regions to a corresponding one of the charge storage cells.

Abstract: The invention provides apparatus and methods for detecting electromagnetic energy using an array of detectors arranged in at least one row and multiple columns. A single crystal body has multiple doped regions disposed therein. Each one of the detectors produces charge in a corresponding one of the doped regions in the body in response to electromagnetic energy impinging upon that detector. A first charge transfer device includes an output port and multiple serially coupled charge storage cells including multiple first charge transfer regions disposed in the body parallel to the row, or rows, of detectors. Multiple second charge transfer devices include multiple second charge transfer regions disposed in the body transverse to the row, or rows, of detectors and the charge storage cells. Each one of the second charge transfer regions is adapted to transfer charge produced in a corresponding one of the doped regions to a corresponding one of the charge storage cells.

Abstract: An Ultra Wideband (UWB) short-range radar system is used for the detection of targets in clutter. Examples of targets on the ground include human walkers, crawlers and runners, and vehicles. The UWB sensor can also be used to detect small approaching boats in different levels of sea clutter or airborne targets like hang gliders. One of the primary differences between this device and other UWB radar sensors is the manner in which the bias on the threshold detector is set as well as the logic circuitry used to find targets in clutter while maintaining a low false alarm rate. The processing is designed to detect targets in varying degrees of clutter automatically. There may be no front panel controls other than an ON-OFF switch. The system is lightweight, low-cost, and can be easily installed in minutes.

Abstract: A method for determining if a motion detector is in a masked condition at the time power is applied to the detector. When power is first applied to the motion detector it enters a mask detection state which runs concurrently with activity and alarm detection routines. Any infrared motion that is detected after the detector has warmed up and stabilized will terminate the mask detection state. If a predetermined amount of microwave Doppler sensor activity is detected within the field of view without detection of infrared activity, a mask condition is declared.

Abstract: An optical parking guide includes a container, a mounting element, either a laser diode or a light emitting diode and a control circuit. The mounting element is pivotally coupled to the container. The laser diode is disposed within the mounting element. The control circuit couples the laser diode to the garage door opener. The control circuit turns on the laser diode in response to the presence of a car with a front window and a dashboard so that the laser diode generates an output light. The mounting element directs the output light through the front window onto the dashboard of the car so that a driver of the car can guide the car into the car's parking place.

Abstract: An animal deterrent system for protecting a specific area. The animal deterrent system includes an infrared detection system for determining when an animal enters the protected area and an electromagnetic field (EMF) generator for communicating with a stimulus delivery system disposed on a collar worn by the pet. The stimulus delivery system produces a non-lethal electrostatic shock which encourages the pet to leave the protected area.

Abstract: A Wiegand sensor is provided as a power source for an external circuit, wherein an alternating magnetic field changes the magnetic state of a Wiegand wire within the Wiegand sensor which, in turn, produces a substantial output pulse that is provided as a power source for the external circuit. The external circuit may be a transmitter that is powered by the output of the Wiegand sensor and upon being powered transmits an information signal to an appropriate receiver. The number of occurrences that the magnetic field alternates corresponds to and is ascertained from the number of information signals that are transmitted. The alternating magnetic field may be generated by magnets coupled to a rotating valve of a gas or water meter such that the occurrence of each transmission of the information signal represents the flow of a predetermined amount of gas or water through the meter.

Abstract: An intruder detection system for detecting the presence of an intruder in a protected area. A light beam, preferably from a laser, is reflected from a target, which is a potential intruder. The time period required for the beam to return to a light detector, as well as the intensity of the reflected light, is recorded. The system includes a computer and software for analyzing the measurements of distance and intensity of reflected light. The algorithm for detecting the presence of an intruder is based on changes in the measured distance and/or intensity of reflected light from initial measurements made during a “learning” period. The system tacks targets using data collected in consecutive searches of the area to be protected. Preferably, an alarm is sounded and/or a video camera is slaved to the system.

Abstract: A dual-sensing intrusion detection device for detecting an intruder comprising a PIR sensor and a microwave sensor. The device comprises PIR processing means and microwave processing means, means for summing the processed PIR signal with the processed microwave signal to generate a summed signal, and means for comparing the summed signal to a sum threshold value to determine if an alarm condition exists. The sum threshold value is selected for optimal discrimination between a human intruder and an animal presence. An additional feature of the intrusion detection device is the generation of a PIR difference signal. This feature allows the device to compensate for the limited bandwidth of the PIR sensor and to be more sensitive to a human intruder. The processing of the sensor signals includes an integration technique that sums the amplitude values of the signal and causes the sum to decay at a slow rate.

Abstract: An electronic camera for capturing images and for reviewing selected images, the camera comprising an arrangement for capturing an image of a real world scene as an image signal, a storage structure for storing captured images and from which stored images can be read, a screen, and a structure for displaying on the screen a graphical representation of a list of the stored images and a user selected location within the list. The camera further comprises a user interface which allows a user to select the location within the list, and a structure for displaying on the screen the image within the list corresponding to the selected location.

Abstract: A humanoid detector for detecting a humanoid in a surveillance area that substantially reduces false intruder indications by having two types of sensors that provide two types of information of the surveillance area, is disclosed. A first sensor detects light images and determines a size of a moving object within the surveillance area and compares the size of detected moving objects to a threshold size to reduce intruder detection caused by small animals. A second sensor detects infrared radiation from the surveillance area provides a detected infrared radiation signal. A decision circuit receives the sensor signals and provides a decision signal that indicates a human intruder in the surveillance area when, simultaneously, the size of the moving body is greater than that of a small animal and the detected infrared radiation indicates that the moving body is a heat producing body.

Abstract: A double superheterodyne type microwave detector is constructed from a reception antenna; a first local oscillator; a second local oscillator; reception means for detecting microwaves having prescribed frequencies based on signals obtained by carrying out a first mixing in which the output of the first local oscillator is mixed with the microwaves picked up by the antenna, and a second mixing in which the signals obtained from the first mixing are mixed with the output of the second local oscillator; judgement means for judging whether or not an actual microwave signal which forms a detection target has been detected by the reception means; alarm means for outputting an alarm when the judgement means judges an actual microwave signal to have been received by the reception means; and first control means for suspending the first mixing when the reception means detects a microwave signal having a prescribed frequency; wherein the judgement of whether or not the prescribed frequency microwave signal detected by t

Abstract: Vertical surface protection in a security installation is achieved by detecting disturbances in a microwave beam sent from a transmitter to a receiver, both installed substantially above the ground and adjacent to the vertical surface. The transmitter and receiver have associated beam aerials of extended horizontal aperture of not less than 0.50 meters (20 inches) to mitigate the effects of surface reflection from metal scaffold, plastic sheeting or netting, wooden boarding and brick or stone facing. The aerials are preferably slotted waveguide arrays and the advantages of using circular polarization are shown. Circularly-polarized slotted waveguide arrays are disclosed having a center feed to minimize frequency-dependent beam-spreading.

Abstract: An electronic device including a wave transmitter covering a determined spatial sensing field, and a wave receiver for controlling an automatic device; a radiating antenna including a waveguide having lateral faces and slots arranged on one of the lateral faces, wherein the slots radiate in planes substantially perpendicular to a longitudinal direction of the waveguide, and wherein the wave transmitter and the wave receiver are arranged at one end of the waveguide; a matched load arranged at an opposite end of the wave guide; substantially identical reflectors arranged over substantially the whole length of the waveguide, wherein the reflectors extend essentially symmetrically with respect to longitudinal plane of symmetry of the waveguide and making a predetermined angle with one another, and wherein the waveguide and the reflectors are composed of at least one piece.

Abstract: A method and apparatus for detecting the presence of objects such as persons in front of a high-frequency communications antenna comprising a transmitting element connected to a circulator. The circulator is connected to an antenna system which transmits the signal pursuant to a designated communications or other application. The circulator is also connected to a regulator circuit which measures a reflected signal received from the circulator. The regulator circuit thereupon initiates a reduction or termination in power from the transmitting element, and/or initiates an alarm, when the regulator circuit detects a reflected signal having a magnitude indicating the presence of the object to be detected.

Abstract: In accordance with the method, the received signal is quadrature demodulated by mixing it with two signals with a relative phase difference of .pi./2 and having the same frequency as the emitted carrier, the absolute value of each of the demodulated signals of each pair of signals obtained is compared to a respective threshold to determine valid pairs if the absolute value of at least one of the two demodulated signals is higher than the threshold and invalid pairs otherwise and the number of successive rotations of the vector whose coordinates correspond to the values of the signals of the successive valid pairs is counted. For each invalid pair the value of the count is progressively reduced. The alarm is tripped if the value of the count reaches a given threshold.

Abstract: An apparatus for detecting the presence or absence of an object within a monitor zone includes a sensor (12) operative to sense a condition of the monitored zone (Z) and provide a sensor signal indicative thereof. The sensor signal is processed, preferably according to two different transfer functions, to provide first and second signals that vary based on the sensor signal. A comparator (46) provides a comparator signal that varies as a function of the first and second signals. Additional circuitry (58) is operative to provide an indication of the presence or absence of an object within the monitored zone (Z) as based on the comparator signal.

Abstract: An apparatus for protecting a keyboard and includes a sound transformer placed in the keyboard and a sound receiver placed outside the keyboard to receive a signal radiated from the sound transformer. The signal is then analyzed to determine if the power of the radiated signal has dropped below a threshold value, indicating potential tampering of the keyboard.

Abstract: A microwave frequency Doppler vehicle intruder alarm comprises an oscillator 3, a mixer 2 and an amplification stage 4, 5 having its output applied to a low-pass filter 7, whose output is split into two branches. A first branch, comprising a rectifier diode and a comparator, provides a signal on its output when a significant level of non-carrier microwave signals is received. This branch is sensitive to signals having Doppler frequencies of 0-200 Hz, which includes the intruder indicative frequencies. A second branch, comprising an amplifier 8, a high pass filter 9, and a comparator 10, provides an output signal on the detection of a significant level of signals in the 40-200 Hz band, which frequencies are indicative of externally generated interference. A logic element 15 mutes the output of the alarm when the second branch indicates the presence of externally generated interference. An antenna arrangement (FIG.

Abstract: A thermal object detecting method for; obtaining a thermal image of a measuring space by two-dimensional thermal image detecting method for detecting two-dimensional thermal image information, obtaining position information of an object in the measuring space by object position detecting device, obtaining distance data between said two-dimensional thermal image detecting device and said object from the position information, and correcting the temperature level of the object in the thermal image in the measuring space or correcting the size of the object in the thermal image in said measuring space, using the distance data from the object as correction factor.

Abstract: A method for initializing an electronic article surveillance (EAS) system which transmits pulses into an interrogation zone and receives signals from the interrogation zone in a sequence of multiple successive transmit and receive windows during each line period of an AC mains supply energizing the EAS system, associated with a corresponding apparatus, comprises the steps of: (a.) determining whether a delay value is stored in a nonvolatile memory; (b.)if the delay value is stored in the nonvolatile memory, loading the stored delay value into a delay control register, terminating the initializing and omitting all remaining steps; (c.) if the delay value is not stored in the nonvolatile memory, loading a first delay value into the delay control register; (d.) determining whether noise in a certain receive window is less than a threshold level; (e.) if the noise is less than the threshold level, terminating the initializing and omitting all remaining steps; (f.

Abstract: A pulse Doppler radar motion sensor system and method for sensing target motion within a gated region is provided with approximately constant response versus target distance. The sensor includes a transmitter for transmitting a sequence of RF bursts comprised of a number of cycles at the transmitter frequency. The transmitted burst width alternates at a pattern frequency to provide a pattern of varying burst widths. The sensor includes a receiver responsive to the transmitted bursts and burst echoes from moving targets within its sensing field. The receiver produces a pattern frequency with a signal amplitude representative of the difference in moving target response for two different range gated regions defined by the transmitted burst widths. This difference is detected to provide a range invariant target motion response in a sharply defined region. Another mode provides a quadrature receive channel for target direction determination.

Abstract: A wireless communication device (101), such as a radiotelephone or a pager, comprises a signal generator (200), a radiator (202), a sensor (204) and a controller (206) to form an electromagnetic wave proximity sensor (201). The signal generator (200) generates a signal (210). The radiator (202) radiates the signal (210) to produce an electromagnetic field (212) near the radiator (202). The electromagnetic field (212) changes by a predetermined amount responsive to the proximity (214) of the radiator (202) to a predetermined object (216), such as a human body (232), external to the wireless communication device (101). The sensor (204) provides an indication (218) of the predetermined amount of change in the electromagnetic field (212). The controller (206) controls circuitry (208), such as a tactile alert device (416) and an audible alert device (418), in the wireless communication device (101) responsive to the indication (218) of the predetermined amount of change in the electromagnetic field (212).

Abstract: Apparatus for monitoring opening of sealed enclosures, especially, but not exclusively, sealed containers containing goods-in-transit, such as goods vehicles, maritime containers or transport containers of the kind carried by tractor-trailers, ships, trains or aeroplanes comprises a radio receiver unit having at least one antenna for reception of radio signals. The receiver unit is housed within the enclosure and operates to scan a predetermined band of radio frequencies, periodically or continuously, and detect a sudden change in signal level. When it detects such a change in radio signal level, the receiver generates an alarm signal. Alternatively, the receiver may detect the difference between internal and external radio signal levels and determine the container to have been opened if the difference is less than a preset threshold.

Abstract: A method for determining malfunction of a microwave intrusion detector which transmits microwave radiation into a region and receives microwave radiation to produce a receiver signal, such that a detection pattern of microwave pulses is transmitted periodically during an intrusion detection mode, including initiating a self-test mode of the detector, transmitting during the self-test mode a test pattern comprising a plurality of microwave pulses having at least two different duty cycles, different from the detection pattern, receiving microwave radiation in the self-test mode and generating a receiver signal responsive thereto and analyzing the receiver signal to derive a parameter responsive to the test pattern, so as to determine a malfunction condition.

Abstract: A non-contact switch movs from an off position to an on position when a lossy material enters a sensitive area of the switch. The non-contact switch comprises a transmitting element and a sensing element. The transmitting element is capable of radiating a signal. A portion of the signal passes through the sensitive area of the switch. The sensing element is capable of receiving the signal. When the received signal is less than a predetermined level, the received signal represents the lossy material entering the sensitive area of the switch.

Abstract: A high sensitive water entry alarm system which prevents outside noise from falsely triggering the alarm system. A transmitter generates ultrasonic timed acoustic bursts at a fixed frequency when it is submerged in water. A receiver located in the body of water senses for acoustic signals similar in characteristic to the transmitter signal. A comparing circuit coupled to the receiver compares the acoustic signals received by the receiver to a reference signal having the same fixed frequency as the transmitter signal. The comparing circuit also measures the duration of the acoustic signals received by the receiver. The comparing circuit will generate a alarm signal which will sound off an audible alarm only when the acoustic signal received by the receiver has the same fixed frequency and is transmitted in controlled burst at the same timed intervals as the transmitter signal.

Abstract: An apparatus for detecting the discharge of a firearm and transmitting an alerting signal to a predetermined location. The invention provides for detection circuitry having: (1) a microphone for detecting pre-set sensitivity levels, (2) a measuring means for measuring acoustic energy generated from the discharge of the firearm, resulting in acoustic energy information, (3) transferring means for transferring the acoustic energy information to a digital signal processor, which converts the acoustic energy information into digital format, resulting in digitized binary codes, (4) an analyzing means for comparing the digitized binary codes contained in the digital signal processor with a set of predetermined criteria, (5) a verification process, and (6) an alerting means for transmitting an alerting signal to a predetermined location in the event the digitized binary codes match the set of predetermined criteria.

Abstract: A light beam, preferably from a laser, is reflected from a target, which is a potential intruder. The time period required for the beam to return to a light detector, as well as the intensity of the reflected light, is recorded. The system includes a computer and software for analyzing the measurements of distance and intensity of reflected light. The algorithm for detecting the presence of an intruder is based on changes in the measured distance and/or intensity of reflected light from initial measurements made during a "learning" period. The system tracks targets using data collected in consecutive searches of the area to be protected. Preferably, an alarm is sounded and/or a video camera is slaved to the system.

Abstract: A microwave motion sensor for detecting multiple levels of motion of a target is disclosed. The motion sensor includes a transceiver for broadcasting a signal into a predetermined area and receiving a reflected signal with a receiver for producing first and second directional signals. A signal conditioning circuit is provided for amplifying the first and second directional signals and digitizing the directional signals. The signal conditioning circuit includes a micro motion amplifier for separately amplifying one of the directional signals and producing a micro motion signal. A processor is provided for receiving the first and second directional signals transmitted by the signal conditioning circuit, and for receiving the micro motion signal. The processor includes a circuit for analyzing the directional signals, and a circuit for comparing the micro motion signal to a threshold.

Abstract: The present invention is a system which will activate an alarm when a garage door is opened. The system in a transmitter unit and a receiver unit. The transmitter unit is attached in proximity to the garage door. The receiver unit is located within a vehicle stored in the garage. The transmitter unit includes a signal generator which activates and transmits radio frequencies (RF) to the second unit. For activation, once the garage door is in an opened position, the transmitter sends a signal to the receiver. The receiver activates an alarm.

Abstract: An arrangement for preventing disturbances in electronic alarm systems of the kind used in merchandise security systems. The alarm system includes an alarm element which is adapted to receive a magnetic alternating field transmitted by a transmitter, and also to retransmit a magnetic alternating field. A receiver is adapted to receive and detect the the retransmitted alternating field. An LC resonance circuit is located in at least certain pairs of electric conductors (5; 12, 13; 20, 21; 25, 26) in the alarm system between the system electronics (2; 16) and a receiver coil (1; 24), and alternatively also a transmitter coil (14). The resonance circuit is tuned to the working frequency or frequencies of the system to produce a high impedance on the conductor pair for current directed in the same direction in the conductors, thereby heavily dampening disturbance sources coupled capacitively, inductively, or resistively to the alarm system.

Abstract: Apparatus for detecting the fall of a person or object into a body of water comprises a series of interconnected modules mounted in a line contiguous to the body, and associated controls. The modules comprise alternately disposed radiation emitters and radiation sensors. The controls are associated with the sensors and adapted to detect perturbations from a steady state condition of the received radiation energy caused by reflections from the falling person or object.

Abstract: An ultrasonic transceiver device and remote output devices controlled by the transceiver for use by domestic pets. The transceiver utilizes a fixed interval edge detect modulation system to lock out stray environmental noise thereby, avoiding false triggering and greatly increasing the working range. Output devices include: a wireless pet containment system in which ultrasonic transmitters are mounted on a series of posts defining the perimeter of the containment area and a receiver device adapted to be worn by a domestic animal.

Abstract: A monitoring device for detecting acoustic vibrations in monitored objects has a plurality of several structure-borne sound sensors which are connected to a remote central electronic analyzing system. The individual structure-borne sound sensors are each acoustically coupled with a self-testing unit, which can be activated from the central electronic analyzing system. Activation of the self-testing units is performed by modulation of an operating voltage supplied to structure-borne sound sensors, without additional electric connections to the electronic analysis system.

Abstract: A proximity detector detects objects which may interfere with a wireless antenna beam. The proximity detector includes infrared sensors, sonar detectors, motion detectors and optical devices to determine a range and bearing of objects that may interfere with the antenna beam.When an object may be harmed or interfere with the antenna beam, an alarm may be activated to warn the user and/or the object of potential harm from the electro-magnetic energy transmitted by the directed antenna. Also, based on the proximity detector's outputs, an antenna beam pattern may be changed to reduce the power at the object or the transmitted power may be reduced to prevent harm to the object.

Abstract: A monitoring and detection system that continually monitors a person(s) presence passing through areas such as rooms, homes, buildings and the like. The system can include multiple operating modes such as a home mode for greeting visitors and normal facility users as well as a secure mode for protecting the facility and occupants from intruders. The novel system provides for multi-task control of all electrical functions in a home such as air conditioning, lights, power and the like. The system can operate events via completely timed static events(i.e. for preselected time periods). The invention can also be used to activate or deactivate events through sensor detection. The preferred embodiment uses ultrasonic sweep sensors which can be programmed to automatically detect person(s) animal(s) that cross protected areas over certain times of the day, week, month based on different conditions, as well as dry contact sensors such as contact switches for doors and windows and the like.

Abstract: An apparatus and method are disclosed for detecting and signaling when a vehicle enters or poses a serious risk of entering a roadway work zone. The apparatus comprises an intrusion detector array for detecting a vehicle breaching the work zone perimeter, and a high intensity strobe light array for providing an optical warning signal when the perimeter breaching vehicle is detected. The detector array includes one or more transmitters for emitting pulsed infrared signals along the work zone perimeter, and one or more receivers for detecting the presence or absence of the pulsed infrared signals, where the receivers include filters for removing stray signals emanating from sources other than the transmitters. The strobe light array includes a primary strobe activated by the detector array when a perimeter breaching vehicle is detected, and several relay strobes which are activated by the optical warning signal emitted by the primary strobe or another relay strobe.

Abstract: Apparatus for reducing electromagnetic radiation from a differentially driven transmission line for high data rate communication in a computerized tomography system is provided. The apparatus comprises a carrier generator, for generating a carrier signal having a predetermined carrier bandwidth. A modulator is respectively coupled to the carrier generator for receiving the carrier signal and for receiving an externally-derived data signal to produce a modulated output signal. The carrier bandwidth is sufficiently broad relative to a predetermined inspection bandwidth for substantially reducing the level of electromagnetic energy being measured over the inspection bandwidth.

Abstract: In order to detect the presence of a marker, an electronic article-surveillance apparatus includes a transmitting circuit coupled to a transmit antenna, a receiving antenna juxtaposed with respect to the transmit antenna, such that an electromagnetic signal is generated within a controlled area, the signal being received by the receiving antenna, such that when the marker is located within the controlled area, a disturbance is created in said electromagnetic signal and is picked up by the receiving antenna. The disturbance is the marker signal. An electronics module receives the electromagnetic signal picked up by the receiving antenna, and a feedback conduit, linking the electronics module with the transmitting circuit, can provide to the electronics module an input to the transmitting circuit which controls the amplitude of the electromagnetic signal so as to maintain the marker signal at a substantially constant amplitude and shape.

Abstract: A small-sized alarm device is hung on a doorknob to emit an alarm sound upon detecting that a human body contacts or approaches the doorknob. The alarm device has data processor, such as a calculator and the like, in addition to an alarm and an electro-optic display for displaying data processed by the data processor and information related to the operation of the alarm. To the alarm device is rotatably mounted a hanging member for hanging the alarm device on a doorknob. The hanging member is fit into the case of the alarm device when in not use or is erected from the case when the alarm device is hung on the doorknob.

Abstract: An intrusion detection system. An RF energy source transmits energy into a ransmission cable that has a characteristic impedance subject to change by deformation of the cable. The cable is buried along a path that corresponds to a perimeter to be monitored. When an intruder places weight in the vicinity of the cable, the cable deforms and changes its characteristic impedance. Consequently a portion of energy transmitted into the cable reflects back where time-domain or frequency-domain reflectometry apparatus uses the reflected energy to identify the location of the intrusion along the cable and provide other characteristics of the intruder.

Abstract: A remote garage door position indicator comprises a magnetic sensor device; a transmitter device being operatively coupled to the magnetic sensor device, the transmitter device being capable of transmitting electronic signals; a signal interruption device including a plate extending therefrom, in closed orientation the outer plate of the receiver device engaging the magnetic sensors of the sensor device thereby closing the electrical circuit and causing the transmitter device to cease sending electronic signals; and a garage door position indicator including a power source and a light, the position indicator including a receiver means capable of receiving electronic signals from the transmitter device, when receiving electronic signals from the transmitter the receiver device causing the light to illuminate, in the closed orientation the transmitter device does not emit electronic signals thereby preventing the receiver device from illuminating the light, users viewing the light of the position indicator to d

Abstract: An apparatus and method for varying the sampling frequency of a Doppler effect device, based on environmental conditions, is described comprising: (i) a transmitter for transmitting energy into a protected area; (ii) a receiver for receiving energy reflected from the protected area and for transforming the received energy into a motion detection signal which is proportional to any Doppler energy received by the receiver; (iii) a processor responsive to the motion detection and operative to automatically modify the sampling frequency when the motion detection signal exceeds a predetermined threshold value and the apparatus has not been operated at each of a plurality of sampling frequencies; and (iv) an alarm coupled to the processor activated when the motion detection signal exceeds the predetermined threshold value and the apparatus has been operated at each of the plurality of sampling frequencies.

Abstract: An underground object indicating device includes a longitudinal sheet material to be buried along and above an underground object. A locator cable is mounted on an upper surface of the sheet material. The locator cable includes a strand of metal wires having high conductivity and a flexible conductive sheath covering the entire length of the metal wire strand.

Abstract: A method of operating a system for monitoring the interior of a motor vehicle in which a rest signal amplitude is measured for the acoustic receiver or receivers in the absence of sound and is stored in memory while an actual reading is taken of the measured signal again in the absence of sound within the vehicle interior and this letter value is compared to the first and an error register is set if the measured value is outside a stored window.

Abstract: A safety device includes a wire loop embedded in the glass of a passenger car window and routed near the closing leading-edge of the window. The wire loop carries microwave pulses around the loop to and from a transceiver with separate output and input ports. An evanescent field only and inch or two in radius is created along the wire loop by the pulses. Just about any object coming within the evanescent field will dramatically reduce the energy of the microwave pulses received back by the transceiver. Such a loss in energy is interpreted as a closing area blockage, and electrical interlocks are provided to halt or reverse a power window motor that is actively trying to close the window.

Abstract: Security systems which include an adjustable structure and a motion detector which detects changes in electromagnetic energy from within a zone of protection are described. The structure has a base for mounting the motion detector and wall members which extend away from the base and to form walls around the detector. The wall members are adjusted to positions between the plane of the base and planes perpendicular to the base to alter the shape of the zone of protection and conform it to the area or object of interest. The motion detector is electrically connected to a control unit and alarm module which includes a shock sensor and a current sensor. The motion detector and the control unit and alarm module are connected to a power supply and operated by remote control.