Abstract: A method for determining the probable response of aquatic species to selected components of water flow fields, comprising the steps of obtaining data for identifying travel and quantitatively describing behavior of real fish constituting members of a selected aquatic species in a flow field, determining passive transport trajectories of the members of the aquatic species in the flow field to establish a basis from which to determine swim path selections, developing postulated behavioral responses of members of the aquatic species to at least one of hydraulic and acoustic stimuli, using statistical rules, and developing a computer utilizing the travel behavior data, the passive transport trajectories, and the postulated behavioral responses, to provide a virtual fish.

Abstract: A mole chaser with improvements in the construction and method of audio frequency and vibration generation includes a main stem, a cap, a battery chamber and a control circuit board, suspended or loosely installed inside of the main stem to make constant contact with inside wall of the main stem, which has a buzzer mounted thereon for generating audio signal to chase away underground rodents, such as moles. The audio frequency produced by the energized buzzer will cause the resonance to circuit board to make it vibrate and strike the main stem to produce more low frequency noise and vibration to enhance mole-chasing effect.

Abstract: An echo-ranging boundary system is provided for controlling the access of animals to predefined areas. An electronic transponder collar is affixed to an animal for exclusion from a predefined area. An ultrasonic beacon, defining a transmission reference point, periodically transmits a directional ultrasonic interrogation signal for determining the location of animals provided with transponder collars. The transponder collar emits an ultrasonic reply signal, detected by the station after a period of time defined by the propagation delay of the ultrasonic reply signal. The propagation delay of the reply signal is directly proportional to the distance between the transponder and the interrogation signal reference point. A timing threshold is set at the transmission station corresponding to a desired control distance. Reply signals returned before a device time-out are compared to the timing threshold.

Abstract: An apparatus for chasing animals from an automobile includes a generator for producing energy which can be sensed by animals, means for mounting the generator to an automobile, and an activation device operatively connected to the generator for activating the generator upon detecting presence of an animal near the automobile. The activation device may include a motion sensor or an infrared sensor. The motion detector may take the form of an ultrasonic sensor, which is sensitive to vibrations in an ultrasonic frequency range.

Abstract: The apparatus according to the present invention is provided with two or more output systems to which transducers are connected, a source output on/off control unit that turns on/off the output from a source based upon the output from a random signal generating unit and a frequency varying unit that causes changes in the frequency of an electrical signal provided to the transducers over time at a specific rate. Every time the source output is turned off, the output of the electrical signal is stopped and the output systems are switched over, whereas when the source output is on, the electrical signal provided to the transducers on the output system to which the signal is to be provided. Since the output systems are switched over to be selected for use, it becomes possible to connect a greater number of transducers while using the same source capacity as in the prior art and noise generated from the transducers, when switching over the output systems, is eliminated.

Abstract: An acoustic annunciator which includes resonating cavity, a piezoelectric element, and a folded horn which are each selected to have a different resonance frequency so as to expand the frequency range of the output of the annunciator. The folded horn includes a cone defined by a main body portion and an outer horn which is rotatable and axially displaceable with respect to the main body portion. The outer horn is designed to rotate to prevent the annunciator from being snagged or caught by objects. The outer horn is designed to be axially displaceable in order to access and remove debris from inside the annunciator. In addition, the acoustic annunciator includes a driver that faces downward during use. This orientation of the driver allows for drainage while preventing the ingress of rain and/or snow.

Abstract: An ultrasonic sound source broadcasts an ultrasonic signal which is amplitude and/or frequency modulated with an information input signal originating from an information input source. If the signals are amplitude modulated, a square root function of the information input signal is produced prior to modulation. The modulated signal, which may be amplified, is then broadcast via a projector unit, whereupon an individual or group of individuals located in the broadcast region detect the audible sound.

Abstract: An automatic feeding system includes a tag attached to a body of a pet; and an automatic feeding apparatus for automatically feeding the pet. The tag includes a receiving device for receiving an electromagnetic wave from the automatic feeding apparatus; an information memory device storing information on the feeding of the pet and outputting the information in response to an output from the receiving device; and a sending device for sending the information which is output from the information memory device to the automatic feeding apparatus using an electric wave.

Abstract: An animal deterrent system for deterring animal intrusion into a specified area using an oscillating ultrasonic tone. The system includes a weatherproof housing containing an infrared detector for detecting the presence of an animal. To identify relevant intrusions, a count of the number of detections is maintained. After the count reaches predetermined number of infrared signals within a predetermined amount of time, an oscillating ultrasonic deterrent signal is generated to distress the animal and deter intrusion into the protected area. A deterrent timer activates the ultrasonic deterrent for a predetermined amount of time. A mounting stake for deploying the system in remote outdoor locations includes an anti-rotation mechanism, to prevent misalignment as a result of incidental contact.

Abstract: The invention is a processor based analysis system with appropriate interface that includes multiple fish surrogates that each have a plurality of piezoelectric and triaxial accelerometer sensors for emulating sensory organs of a particular fish. The multiple fish surrogate array is immersed in flowing water intakes of a hydraulic structures such as intakes, intake bypasses, and diversion structures, and natural geological formation such as riffles, shoal areas, and pools. The invention is an interface system for data acquisition analysis and perspective display of acoustic and fluid dynamic data in or near these hydraulic structures and/or natural formations. To accomplish this, multiple sensors in each of the fish-shaped surrogate physical enclosures that form the array are deployed at the same time to describe a fish's aquatic environment at the hydraulic structure location.

Abstract: An acoustic cannon has a plurality of acoustic sources with output ends symmetrically arranged in a planar array about a central point. Pressure pulses are generated in each acoustic source at substantially the same time. The pressure pulses exit the output ends as sonic pulses. Interaction of the sonic pulses generates a Mach disk, a non-linear shock wave that travels along an axis perpendicular to the planar array with limited radial diffusion. The Mach disk retains the intensity of the sonic pulses for a time and a distance significantly longer than that achievable from a single sonic source. The acoustic cannon is useful as a non-lethal weapon to disperse crowds or disable a hostile target.

Abstract: A Warning system in combination with a vehicle in which ultrasonic sound and ultraviolet is beamed in advance of the moving vehicle on a thoroughfare so that said sound and light may be heard and seen by an animal ahead of the moving vehicle to induce the animal to leave the road before it is struck by the vehicle.

Abstract: An acoustic impulse source has been developed and used to simulate the high coustic output of detonation driven acoustic sources. While detonation driven acoustic sources are capable of producing large acoustic signals (>160 dB) at 10s and 100s of meters from the source, their laboratory use is limited due to the combustion byproducts. The present invention is capable of reproducing the downrange detonative source acoustic signals (170 dB) at short range, on the order of 1 meter, without noxious or large thermal byproducts. The present invention relies on the plasma formation resulting from electrical arc discharge in air to generate thermal impulses and the resultant acoustic signals. Utilizing multiple plasma channels and timing control of the formation of said channels, the present invention achieves increased efficiency and the ability to tailor the acoustic output signal to match the desired detonation source characteristic output.

Abstract: Signals generated electronically at a variety of frequencies are broadcast under water in the presence of various species of aquatic animals and any reaction of the aquatic animals in response to the broadcast signals is noted. A frequency synthesizer is used with an underwater transducer to generate and broadcast signals at a variety of frequencies and frequency synthesizer control words associated with observed behavior are recorded. Subsequently, the recorded control words are applied to a frequency synthesizer connected to an underwater transducer to influence behavior of identified species of underwater animals in a desired manner. Indices representative of various recorded signals may be embodied in a submersible device, such as a lure or the like, from which a reproduced signal may be broadcast to attract, repel, or otherwise influence the behavior of identified species of aquatic animals.

Abstract: A repeller includes a tube receiving a covering device connected to a frame via a connector. A handle is pivotally connected to a top of the covering device. The frame contains a repelling device and batteries. The connector is configured to have a hole defined in a surface thereof, a shoulder formed in parallel with the surface and an extension vertically extended downward from the shoulder, such that the connector is able to be connected with the covering device through the hole and mounted to the frame via the extension. Accordingly, a user is able to raise the batteries upward by just simply lifting the handle.

Abstract: A new Vehicle Animal Repelling System for repelling unwanted animals from a vehicle. The inventive device includes a control unit, a plurality of exterior speakers electrically connected to the control unit, a solar panel electrically connected to the control unit and a frequency controller electrically connected to the exterior speakers.

Abstract: A method of alerting sea cows to the existence of danger underwater includes generating a modulated acoustical signal in a predetermined source frequency band and sound pressure level and projecting the generated signal underwater in a directional manner and in a direction corresponding with the direction of travel of a motor vessel, wherein the projected modulated acoustical signal has an underwater frequency ranging between 3 kHz and 26 kHz.

Abstract: A wide angle frequency automatic scanning ultrasonic animal chaser for scaring away straying cats and dogs includes a case, an end plate, a water resistant cover and an ultrasonic oscillation circuit held in the case. The case and the end plate are housed in the cover by means of ridges and troughs without using hand tools. The ultrasonic oscillation circuit includes a divider and a stable multivibrator circuit for generating ultrasonic oscillation frequency and emitting through a perforated plate located at a front end of the case. The oscillation circuit provides an automatic scanning frequency function to effectively scare away straying cats and dogs nearby. This device consumes little power and is easy to install and use.

Abstract: An apparatus for repelling animals from an automobile is mounted in an automobile having an engine compartment and an automotive battery. A generator for producing vibrations which can be sensed by animals is mounted in the engine compartment. The vibration generator is wired to the automotive battery for supplying electrical energy from the battery to the generator. A switch is connected to the vibration generator to switch the vibration generator between an activated state, in which the generator generates vibrations, and a deactivated state, in which the generator does not generate vibrations. The switch may be connected to the ignition of the automobile to deactivate the generator while the ignition is activated, and to activate the generator while the ignition is deactivated.

Abstract: An improved fish deterrent and guide utilizing generally a pneumatic oscillator (1) and oscillated plate (9), to generate water particle motion (low frequency sound or infrasound) and specifically water particle accelerations to which fish exhibit an avoidance response. The invention is reliable, reasonably portable and deployable, low-maintenance, and tunable to produce the desired water particle motion. Reliability is due to the piston (4) being cushioned by air at the end of each stroke and redirected without impacting the casing. The operation of the apparatus is easily verified from the water surface by inspection of the backpressure regulator (13). The apparatus is tunable through adjustment of the inlet pressure, backpressure, and size, shape, and mass of the oscillated plate.

Abstract: Method and means for preventing trespassing and/or unauthorized staying in an area outdoors or indoors, e.g. in a building, part of a building, in vehicles, vessels, etc., sound signals with periodically varying frequencies with the variation of the frequencies out of phase are transmitted from several sound generators in such directions that the sound waves from the sound generator meet within the area to be protected.

Abstract: A position-dependent switch to sense deployment of an underwater pinger to enable operation upon deployment. During underwater deployment the pinger orients itself differently from an orientation chosen for the stowed (not deployed) condition. The position-dependent, or orientation-dependent, switch senses the pinger orientation and enables pinger operation automatically upon deployment. When the pinger is stowed the position-dependent switch disables the operation of the pinger.

Abstract: The apparatus of this invention are multiple fish surrogates that each have plurality of piezoelectric and triaxial accelerometer sensors for emulating sensory organs of a particular fish. The multiple fish surrogates are immersed in flowing water intakes of a hydraulic structure such as: intakes, intake bypasses, and diversion structures; or also natural geological formation such as riffles, shoal areas, and pools. The invention is used for acquisition of acoustic and fluid dynamic data in or near these hydraulic structures and natural formations. To accomplish this, multiple sensors in multiple fish-shaped physical enclosures are deployed at the same time to describe a fish's aquatic environment at locations such as in proximity to a dam's intake. Since such an intake exhibits turbulent and high energy flow fields that cannot be characterized by a single sensor, many sensor bodies are required for a complete characterization of the environment.

Abstract: Acoustical shock waves are generated by electrical sparks within a gap between electrodes adjustably positioned for exposure to water adjacent a surface immersed therein. High voltage electrical energy derived from a constant current power supply, is stored in a capacitor for rapid. application to the electrodes by discharge during cyclic periods of short duration under remote control in order to render the acoustical shock waves so generated effective in preventing biofouling of the surface by organisms in the water.

Abstract: An acoustic resonance chamber in an underwater pinger is designed to enhance the acoustic emission from the pinger. An electro-acoustic transducer of the pinger is positioned away from a reflective surface of the pinger housing by a distance chosen in proportion to the wavelength of the fundamental frequency of the acoustic emission. This creates a resonant condition at the transducer, maximizing the acoustic output. This design also causes a maximum transfer of the acoustic wave through the pinger housing and into the surrounding water.

Abstract: An acoustic system and a method for repelling marine mammals from a region of water is disclosed. A plurality of acoustic transducers (10,12,14,16) are spatially dispersed beneath the surface of the water. The transducers (10,12,14,16) in sequence output high frequency acoustic signals into the water. The power of the acoustic signals starts at a low level and is gradually or incrementally increased to a high level which produces a signal beyond the threshold of pain of the mammals to be repelled. The mammals are therefore gradually repelled from the area without suffering permanent hearing loss.

Abstract: An ultra-sonic dog-expelling device, which comprises an upper casing, a lower casing and an ultra-sonic oscillation circuit; the tuner walls of the upper and lower casings are furnished with click grooves and fastening tongues respectively so as to have the two casings assembled together quickly. The inner side of each casing is furnished with a screw hole so as to facilitate the casings to be assembled into a closed case. By means of an intermittent unstable multi-oscillator, an intermittent oscillation frequency can be provided, and can be convened into an ultra-sonic wave through an ultra-sonic wave transducer located in the round hole at the front portion of the two casings to annoy and interfere the hearing sense of a dog so as to expel the dog away and to prevent it from attacking or nearing a person.

Abstract: A deterrent system is provided for repelling selected species of aquatic animals from an underwater deterrence zone, for example, from the opening of a municipal or industrial water intake. A conduit for fluid, generally water, has an outlet at the deterrence zone. Intermittent flow means cause one-way fluid flow through the conduit, visiting at the outlet as pulses of fluid alternating with periods of insubstantial fluid flow. The pulses have a volume and flow rate sufficiently in excess of the insubstantial fluid flow to repel the selected aquatic animals from the deterrence zone. The conduit outlet does not serve also as a substantial fluid inlet to the conduit and, rather, the system provides substantial net positive outflow from the conduit outlet over one or more full cycles of the aforesaid pulsed fluid flows alternating with periods of insubstantial fluid flow.

Abstract: An integrated system which provides an extension of the effective operational area of a single unit ultrasonic pest repeller is disclosed. A master unit produces selectable acoustic waveforms from a speaker and also produces selectable electronic output signals for delivery to a first satellite unit. The first satellite unit produces a similar acoustic repelling waveform and also replicates the master unit electronic output signal for delivery to an identical second satellite unit. Each subsequent satellite unit in a serial chain of satellite units is powered by its own wall plug-in transformer so that the chain may be as long as necessary to accomplish deterrence of roaches, insects including bees, and rodents from the entire area to be protected.

Abstract: A barracuda-repelling sound generation device including a sound generator mechanism for generating a speaker activation signal when electrically energized; a remote speaker mechanism positionable beneath the surface of a body of water for generating a noise irritating to barracudas upon receipt of the speaker activation signal; a speaker cable mechanism for transferring speaker activation signals from the sound generator mechanism to the speaker mechanism; a power supply mechanism for supplying electrical energy for operation; and a power switch mechanism for selectively supplying electrical energy to the sound generator mechanism.

Abstract: A method of alerting marine mammals and other mammals underwater to the danger of approaching motor vessels includes generating a pulsed acoustical signal at a predetermined source frequency and at a fixed or variable (with boat speed) sound pressure level and projecting the generated signal underwater in a highly directional manner from a motor vessel and in a direction corresponding with the direction of travel of the motor vessel or from fixed hazards which present a danger to mammals underwater; the projected pulsed acoustical signal having an underwater frequency ranging between 3 kHz and 26 kHz.

Abstract: An anti-fouling system for producing vibrations in an underwater structure to inhibit the attachment of aquatic life forms to the structure. The system includes a controller which drives one or more transducer. The transducer comprises a housing, one end of which is closed by a resilient diaphragm. An electromagnet with soft magnetic core is contained in the housing spaced from an unsupported portion of the diaphragm. The unsupported portion of the diaphragm is mounted over an underwater structure. In operation, the electromagnet is excited with a current pulse, which deforms the diaphragm so that the housing moves towards the structure. As the current drops off, the diaphragm is restored to its original shape and the housing moves away from the structure imparting a vibrational force to the structure. The transducer includes an elastic membrane to compensate for changes in temperature and pressure commonly found when working under water.

Abstract: Acoustic signals and hydraulic pressure variations which influence fish bvior in bodies of water are measured and recorded by apparatus simulating a fish immersed in water, fitted with piezoelectric transducers and connected by wiring to remote amplifying and recording means. Such data are correlated with fish behavior for the purpose of developing methods of diverting fish from such areas of danger as the intake piping of hydroelectric power generating turbines and pumping stations.

Abstract: A complete vehicle accident prevention system utilizing electromagnetic transmissions for the purpose of: 1) alerting drivers to the presence of certain unanticipated accident threats such as pedestrians, bicyclists, joggers, emergency vehicles, disabled vehicles, etc.; 2) alerting people using the roadway that a vehicle is approaching thereby inducing them to move to the side of the road. The system also utilizes a speaker assembly mounted on the vehicle to forwardly transmit a pre-programmed array of natural sounds having a frequency audible to the typical human ear for the purpose of inducing animals and people to vacate the path of the approaching vehicle. The controller may receive data from a radio direction finder to cause the display to indicate to the driver of the vehicle the relative position of a potential road hazard.

Abstract: A structure of an pest and insect expeller of an electromagnetic type comprises astable multivibrator circuits an electromagnetic sound generator, a heat dissipation system, and conductor power wires, wherein the astable multivibrators produce a series of intermittent and varying signals. The electromagnetic sound generator makes use of the inductance of an electromagnetic field to create physical vibrations, resulting in electromagnetically vibrated sound waves. The sound waves are delivered by the medium of conductor power wires to all indoor power lines and ground wires connected to the apparatus of the invention, and are distributed all over room corners, cracks on walls, and gaps so that insects will feel uncomfortable and get out of hidden places, as a result, the apparatus can achieve its effect.

Abstract: Water is treated with sound waves produced by means of a submerged plasma sparking device (16) to mitigate detrimental effects of aquatic organisms in the water. For example, the incrustation of zebra mussels may be reduced by killing the zebra mussels or creating an environment hostile to them. The plasma sparking device may have a main storage circuit (14) which includes liquid dielectric capacitors or cryogenically cooled field coils for storage. Moreover, the electrodes (50) of the plasma sparking device may be of aluminum or an aluminum alloy.

Abstract: An animal warning device for alerting, and in turn warning, various animals, such as deer, through one or more tones audible to animals, that a vehicle, to which the device may be attached, is approaching. A housing member, which supports a speaker, is adjustably attachable to a vehicle. The housing member includes a dispersing region operatively associated with the housing member for dispersing the one or more tones broadcasted out of the speaker in a radiated, spray-like pattern.

Abstract: A method and sound wave generating assembly for keeping a surface free of scale, fouling and dirty generated by the adherence of in water-living organisms such as marine life, the surface being part of a body that is in contact with water, the method comprising the step of generating and emitting, from at least one location of the body, at least one high-frequency sound wave train, forming, adjacent the body surface, a vibrating field encircling the body surface, wherein the molecular kinetic energy of the water within the field is increased to generate a drastic drop in the density of the water as well as in the density of the cells of the organisms entering the vibrating field, thus alterating the habitat of the organisms and discouraging the organisms from adhering to the body surface.

Abstract: A method and apparatus for using the primordial fear of dolphin of killer whales to separate dolphin from tuna. The sound of killer whale is recorded, digitized, edited and enhanced to produce digitally synthesized killer whale sounds. These digitally synthesized sounds of one or more feeding killer whale is played under water and in the vicinity of a mixed school of dolphin and tuna and as the dolphin leave said vicinity, catching the tuna in nets. A playback unit is selectively triggered on and off from a remote location.

Abstract: A process and apparatus for catching fish, provided with a food container having an ingress opening and an egress opening, as well as a catch container having an ingress opening. Each of these openings is provided with a frustum-shaped fish trap element having openings on both ends. During operation, the food container is lowered into a body of water and a signal is generated in the body of water attracting fish to the food container as bait food is dispensed into the food container, for the purpose of training fish to swim therethrough. When it is desired to catch fish, the catch container is lowered into the body of water having an access opening which is aligned with the egress opening of the food container. At this time, the signal is generated and food is dispensed into the food container causing the fish to move from the body of water into the food container and then into the catch container.

Abstract: The invention is a fishing net system which is selective for catching one or more species and for excluding one or more species. It includes a fishing net having webbing of adequate size to catch one or more desired species a sound transmitting unit and one or more underwater speakers. The sound transmitting unit is at a remote location, e.g. on a boat, and the speakers are located, within close proximity to the fishing net. The speakers emit sounds which offend one or more species and frighten them away from the net without offending other species.

Abstract: An electronic alarm is disclosed for use in a moving vehicle which generates ultrasonic sound for preventing animals from moving into the path of the vehicle. The device includes a simplified driver circuit for generating electrical impulses in the form of square waves having constant peak-to-peak voltages. The driver generates the square waves with periodic, sequentially increasing wave frequencies followed by sequentially decreasing wave frequencies. A coupling transformer converts the square waves into electrical sine wave voltages having high peak-to-peak voltages to cause a piezo-electric transducer to emit intense, ultrasonic sounds of periodically increasing frequencies followed by periodically decreasing frequencies simulating the warble effect of a siren without excessive heating and premature failure of the transducer. The ultrasonic warble effect confuses the animal to prevent inadvertent movement by the animal into the oncoming vehicle's path without injury to the animal.

Abstract: A microwave oven includes a magnetron generating microwaves which are irradiated onto food for heating the same, a circuit substrate incorporating an electric circuit for driving and controlling the magnetron, circuit means for generating both an electrical alarming signal and a high-frequency electrical signal, and a sound producer producing an alarming sound regarding a heating operation when supplied with the alarming electrical signal and producing ultrasonic waves for the repelling of insects when supplied with the high-frequency electrical signal.

Abstract: Improvements on the Parra "METHOD AND APPARATUS FOR SEPARATING DOLPHIN FROM TUNA" using the primordial fear of dolphin of killer whales to separate dolphin from tuna wherein the sound of feeding killer whale is recorded, digitized, edited and enhanced to produce digitally synthesized killer whale sounds. These digitally synthesized sounds of one or more feeding killer whale is played under water and in the vicinity of a mixed school of dolphin and tuna and as the dolphin leave said vicinity, catching the tuna in nets. According to the present invention, one or more of a plurality of playback units are selectively triggered on and off from a remote location to steer the dolphin to safety. The playback unit is carried in an elongated hollow tube having a weighted end and a recovery end, the weight causing the end it is on to go to a predetermined depth in the sea with the recovery end having a hook for aerial retrieval.

Abstract: A small, compact motion detector alarm is sensitive to low frequency vibration (20 to 250 Hz) and emits an alarm sound when this vibration is detected. A piezoelectric transducer element serves as a low frequency sensor and also produces an alarm sound near its resonance, nominally 5 KHz. When low frequency vibrations occur, a detector formed of a amplifier and a current comparator actuates a one-shot which turns on an oscillator circuit to drive the transducer. A time out circuit disables the one-shot for a few seconds after the alarm has sounded, so that the device can return to its standby state. The alarm can be made to emit in the human audible range or in the ultrasonic range, which will be effective with pets but will not disturb humans.

Abstract: An ultrasonic sound emitting apparatus produces an undesireable noise for animals such as dogs and cats to deter such animals from trespassing within certain geographical locations with this noise being of such a high frequency level that it is not heard by most human beings. The apparatus includes a housing with an ultrasonic emitter being mounted within a reflector cone formed within the front face of the housing. The sound emitter is moveable relative to the cone between a projected position and a retracted position and when in the retracted position the pattern of sound emitted is substantially wider than when the emitter is in the projected position. With the emitter in the projected position the pattern of sound emitted is of substantially greater length than the pattern of sound with the emitter in the retracted position. A sensor such as an infrared sensor is to be mounted within the front face of the housing which will cause activation of the emitter only upon an animal being detected.

Abstract: A supersonic sound emitting device consisting of a power source, a supersonic wave signal generator supplied with a power from the power source and for generating a supersonic wave signal and a supersonic sound emitter supplied with the supersonic wave signal from the supersonic wave signal generator and for emitting a supersonic sound, wherein the power source has a solar battery, a secondary battery charged by the solar battery, and an on-off switcher for making the secondary battery on and off.

Abstract: An apparatus and method utilizing a sweep-frequency, high voltage generator coupled to an applicator gun for feeding electric power into pest-infested dielectrics, for example termite-infested wood. Utilizing a conventional line frequency of 120 or 60 Hz, the generator produces 140 kilovolts propagated within a spectral band ranging from 15 to 120 kHz and rich in harmonics. Output is discharged through a high-voltage energy storage capacitor charged using an insulated gate bipolar transistor driven by a variable frequency inductively coupled multivibrator. The output voltages penetrate dielectrics and electrocute the pests inside. The invention is effective against insects having hard exoskeletons comprised substantially of cuticulin, chitin, and sclerotin.

Abstract: A sound wave generator is effective for producing ultrasonic sound wave vibrations as well as low frequency vibrations which are offensive to rodents. A wiring conductor which serves as a sonic radiator is attached to an end portion of a solenoid rod which is reciprocated by a coil which is energized by alternating current power. The solenoid rod is permitted to vibrate within a hollow spool, and the sonic radiator is mechanically coupled to the solenoid rod by a high compliance, conductive metal spring. Ultrasonic sound waves are produced by forming the solenoid rod of a ferromagnetic material which is characterized by magnetostriction in the presence of an alternating magnetic field. The amplitude of sound wave vibration is intensified by selecting the length and diameter of the solenoid rod so that its natural frequency of vibration is in harmony with either the pulse frequency of the electromagnetic driving force, or alternatively, the frequency of ultrasonic sounds produced by magnetostriction.

Abstract: A mole chaser, which comprises a main stem, a cap, a battery chamber, and an audio frequency circuit; the main stem and the cap are fastened together with threads, whereby battery chamber and the audio frequency circuit can be sealed in the main stem. The lower end of the main stem has a point end to facilitate the main stem to be planted in ground. The audio vibration signal is to be sent out through the main stem to chase moles. Through the special design of the battery chamber, the whole chaser becomes simple in structure, such as the battery chamber can be pulled out easily for replacing battery, and the main stem can be closed and sealed with the cap to become waterproof.