Abstract: A safety device is used to protect golfers located in blind areas of a golf course from balls being driven, for example, off the tee. The safety device is manually activated by a push-button switch once the golfers enter the blind area. The switch initiates a low current drain, high-intensity, strobe light blinking at a 1 Hz rate that is visible from both the tee and blind areas even in bright sunshine. An electronic timer deactivates the strobe after N minutes. A wireless transmitter link located outside the blind area can be used to recycle the timer prior to the elapsed time (minutes) for those golfers who play more quickly.

Abstract: A batteryless sensor includes either a micro miniature generator/gear train or a piezoelectric crystal to convert a movement of a door or window to an ersatz V.sub.cc transient power supply to radiate a coded RF signal to a receiver, a distance away. The receiver may monitor a multiplicity of sensors to identify a source of an intrusion.

Abstract: A four-terminal network in tandem with a tunnel diode (TD) threshold receiver currently used in radar or communications improves its sensitivity. Previous inventors have shown that the temperature and sensitivity properties of a conventional TD threshold device used for detecting very short duration bursts of microwave energy would be enhanced by appropriately biasing the TD by a current derived from the thermal noise; the current sets the TD operating point. The magnitude of the current is determined by a constant false alarm rate (CFAR) feedback loop. The subject invention recognizes that a TD changes states (i.e., a detection event) when the area under the current vs. time curve or the charge passing through the device exceeds a prescribed number of picocoulombs. To maximize the charge and improve detection, a form of superheterodyne conversion is introduced to convert the oscillatory short pulse microwave signal received by an antenna to a monopolar baseband signal.

Abstract: A batteryless sensor includes a small and concealed permanent magnet motor which operates as a generator to convert rotational or translational energy to an ersatz Vcc transient power supply via a mechanical arrangement to radiate a coded VHF oscillator signal to a repeater or central processing unit located as far as one mile from the sensor. The receiver is able to monitor a multiplicity of sensor units over a given time period.

Abstract: This invention describes a high voltage, very short pulse, microwave radiating source using low-cost components, and capable of operating at high pulse repetition frequencies (prf). The source is activated by an ordinary video trigger commensurate with driving TTL logic. A trigger will cause a chain of N (where N may be 12 or greater) avalanche transistors connected in a Marx generator configuration to threshold resulting in a 1,200 volt or greater baseband pulse having a rise time of less than 100 ps and a duration of about 3 ns driving the input port of a dipole antenna. The dipole is excited by a balun. This invention achieves very short pulse duration broadband microwave radiation at pulse repetition frequencies as high as 30 kHz or greater.

Abstract: This invention describes a high voltage, very short pulse, microwave radiating source using low-cost components, and capable of operating at high pulse repetition frequencies (prf). The source is activated by an ordinary video trigger commensurate with driving TTL logic. A trigger will cause a chain of N (where N may be 12 or greater) avalanche transistors connected in a Marx generator configuration to threshold resulting in a 1,200 volt or greater baseband pulse having a rise time of less than 100 ps and a duration of about 3 ns driving the input port of a dipole antenna. The dipole is excited by a balun. This invention achieves very short pulse duration broadband microwave radiation at pulse repetition frequencies as high as 30 kHz or greater.

Abstract: A transmitter array includes a number of individual transmitters, each contributing a series of short microwave pulses each consisting of only several cycles to make up an RF pulse in the far field. Apparatus for closed loop synchronizing the pulses from each transmitter in order to maximize the amplitude of the RF pulse includes a Voltage Control Oscillator which provides a continuous wave (CW) reference to each transmitter and includes apparatus for dividing the CW down to feed a series of timers in each transmitter, each timer having a means for setting the time and duration of firing and providing an output signal synchronously related to the CW. A dual polarity peak detector fine tunes the individual transmitters via closed loop feedback to compensate for any thermal drift. A novel time delay vs. voltage transducer is used to achieve closed loop synchronization. Short term pulse jitter is significantly reduced by overtriggering the avalanche transistor.

Abstract: A short pulse radar receiver having a detector with a threshold automatically adjustable with the level of noise and interfering signals. Interfering signals at signal levels which exceed the maximum for which a threshold may be achieved to prevent a false alarm are attenuated prior to coupling to the variable threshold detector by an attenuator variable automatically in accordance with the received signal level.

Abstract: A base band radio speed sensor, for use with the path of travel of the craft whose speed is to be sensed advantageously disposed at right angles to the antenna patterns, utilizes a transmitter flanked by equally spaced receivers for determining the times of passage of the craft with respect to symmetrically disposed receiver antennas.

Abstract: A detector which is subject to temperature variations and power supply drift including a tunnel diode circuit having first and second stable states and a variable threshold that is sensitive to noise and input signals within a useful frequency band and produces output signals when the amplitude of the noise or the input signals exceeds the instantaneous value of the variable threshold to cause the tunnel diode to switch from its first low voltage stable state to its second high voltage stable state. A control circuit coupled to the tunnel diode produces a square range-gate pulse having a pulse width which determines the interval during which the detector is sensitized and produces a reset pulse in response to the leading edge of the square range-gate pulse which sets the tunnel diode in its first stable state.