Abstract: The present invention relates to systems and methods of tracking and/or avoiding harm to certain devices or humans. According to one exemplary embodiment, a method of tracking individual assets may include obtaining position data of an asset via a GPS receiver in communication with a position sensor associated with the asset, processing position data and sensor data via a processing component associated with the position sensor that receives the position data from the GPS receiver, and communicating sensor data to a host device via a communication interface associated with the position sensor and configured to enable wireless communication between the position sensor and the host device.

Abstract: Provided is a detector for fishing in order to detect the depth of water, the temperature of water, the distribution of fishes including fishes' migration and/or the length of fishes.

Abstract: A low cost, low power consuming display for a solid state depth locator is provided. The display has no moving parts yet provides a real-time output indicative of the depth, size and density of targets in a body of water using colored LCDs.

Abstract: The invention relates to a method for the visualisation in a single image of the useful information obtained by the operation of an active sonar with line spectrum emission. The method permits an operator to simultaneously view the echoes which may need monitoring and the trace left by the sonar wave reverberation, seabed, surface or volume reverberation. Said method comprises at least three phases: one phase for Doppler processing (71) particularly for differentiation of the fixed echoes from mobile echoes, a step for generation (72) of an artificial sonar image positioning the detected echoes in a direction/distance plane, a step (73) comprising the replacement in the artificial image of a representation derived from the reverberation, in particular of that from the marine bed. Said method is particularly suitable for sonar systems using the Doppler effect to characterise the received echoes.

Abstract: A system for locating and identifying an acoustic event such as gunfire. The inventive system employs a plurality of man wearable acoustic sensors for detecting gunfire, each acoustic sensor having a display associated therewith for displaying information concerning the acoustic event to a user. In preferred embodiments, the sensor includes a microphone for/receiving acoustic information; an A/D converter; a processor for processing the digitized signal to detect a gunshot and determine a time of arrival; a GPS receiver for determining the position of the acoustic sensor; and a network interface for bidirectional communication with a system server. Preferably the display comprises an LCD; and an electronically readable compass. When the display and acoustic sensor are in separate housings, the acoustic sensor includes a transmitter and the display includes a receiver for transferring the gunshot information.

Abstract: A fish length measuring apparatus that incorporates a digital scale allows fishermen to both measure and weigh their catch without touching or handling the fish. The apparatus incorporates a housing with a lip grip to grasp the mouth of the fish. A viewable digital output screen is connected to a weight-sensing member whereby the weight of the fish generates a digital numeric display. A distance-measuring sensor projects a beam towards a surface adjacent the tail of the fish and detects the reflection from that surface, then calculates the distance (i.e., length) and displays the length on the output screen. The contour of the housing facilitates hand-holding of the apparatus, and a variety of unique digital data may be selectively displayed on the output screen.

Abstract: Remotely operable electronic apparatus are applied to distance measurement and picture/sound recording wherein, for example, a remote unit may be equipped with a microphone and an active range finder coupled to an auto-focussing capability. In one embodiment a camera is adapted to transmit a signal to the remote unit which returns a signal enabling the camera to accurately calculate distance and adjust focus in accordance with time-of-flight. The transponder preferably forms part of a wireless microphone, with the signal transmitted by the camera being preferably acoustical in nature. The acoustical signal transmitted by the camera is preferably modulated onto a return RF signal, enabling at least a portion of the audio circuitry associated with voice modulation to be used for the purpose of modulating the ranging signal, thereby realizing a very efficient and economical approach to remote sound detection and active ranging finding.

Abstract: Apparatus and methods of monitoring mooring lines of an offshore drilling rig, with the apparatus including a communication system in communication with a global positioning system, providing position coordinates of the apparatus at a first point on the line, and also includes an inertial navigation system supported by the frame, providing position coordinates of the apparatus at a second point on the line, by double integration with respect to time of inertial accelerations measured by the device as it is moved from the first point to the second point. Correction at the second point is provided by obtaining at the second point, depth, position relative to magnetic north, and deviation from vertical.

Abstract: A fish depth monitor is a device that can display first water depth data that indicates the location of terminal tackle that is engaged on fishing line reeled out from a spool, and second water depth data that indicates the location of the bottom of a fishing location transmitted from a fish finder, and includes a case, first and second reception portions, a display unit, and a control unit. The first and second reception portions receive the first water depth data from an electric driven reel and the second water depth data from the fish finder. The control unit graphically displays the received first and second water depth data in positions that correspond to the water depth on the display unit. It is possible to intuitively determine the positional relationship between the location of the terminal tackle and the location of the bottom.

Abstract: The invention is a digital sounder module and its method for detection. The digital sounder module includes a sonar carrier wave producing means, a band-pass filter, a pre-amplifier for providing a high sensitivity and extending a wide dynamic range, and an analog-to-digital converter for providing a digital implementation of a superheterodyne detector and producing an intermediate frequency. The digital sounder module also includes a programmable logic device for controlling a gain of the pre-amplifier and for digitally filtering the intermediate frequency and a microprocessor. The method implemented by the controlled per-amplifier gain processes the return echo signal by controlled ramp up of the gain over time to compensate for the change in signal strength in proportion to the length of the return path.

Abstract: A portable ultrasound height measuring apparatus, which comprises a display module and a measuring module. Wherein the display module comprises a LCD, a speaker, a transparent plank and a skidproof pad. The measuring module comprises an ultrasound emitter, an ultrasound receiver, a start button, a set fingerboard, and under the set fingerboard a microprocessor. The apparatus measures height of measured person by emitting an ultrasound signal from the emitter and receiving a reflecting signal by the receiver, then displays value on the LCD. The display module and measuring module are jointly connected together to make the display module able to rotate, open, and close in a set range of angle relative to the measuring module.

Abstract: The invention is a digital sounder module and its method for detection. The digital sounder module includes a sonar carrier wave producing means, a band-pass filter, a pre-amplifier for providing a high sensitivity and extending a wide dynamic range, and an analog-to-digital converter for providing a digital implementation of a superheterodyne detector and producing an intermediate frequency. The digital sounder module also includes a programmable logic device for controlling a gain of the pre-amplifier and for digitally filtering the intermediate frequency and a microprocessor. The method implemented by the controlled per-amplifier gain processes the return echo signal by controlled ramp up of the gain over time to compensate for the change in signal strength in proportion to the length of the return path.

Abstract: A submersible ice fishing troller system for efficiently trolling a fishing lure or bait beneath an ice surface. The submersible ice fishing troller system includes a submersible unit in communication with a control unit, sonar for bottom and fish detection, a downrigger clip attached to the submersible unit, and a line release attached to the submersible unit. An actuator unit mechanically connected to the line release allows for selective release of the fishing line from the line release after a fish has bitten. The submersible unit automatically travels to the bottom of the ice after the line release has been opened.

Abstract: A system for sonically probing a seabed comprises at least one row (14) of transducers (22) that each can produce a sonic beam, and at least one sonic detector (24). Each transducer is independently energized to produce a narrow sonic beam (40), with resulting seabed or subsea echoes being detected to produce one pixel of a display (60, 80, 90, 150) formed by an X-Y array of pixels, before a next transducer is energized and its echoes are detected to produce another pixel of the display. When the system detects a large change in echo amplitude at adjacent seabed locations, then scanning at those locations is accentuated by analysis and by additional sonification at different frequencies. The transducers are closely spaced, at a center-to-center distance (G) of less than 25 cm, to provide good horizontal resolution and usually lie within 6 meters from the seabed. Each transducer is energized to produce a sonic pulse which, dependent on the application, has a carrier frequency (32) of at least 200 kHz.

Abstract: A position locating device for identifying the distance and direction from a first object located with a user to a second object. The first object transmits a signal to the second object. The second object returns a signal to the first object. Microphones are arranged around the first object such that the time at which a microphone receives the returned signal is related to the direction of the second object relative to the first object. A receiver located at the first object decodes and analyzes the signal and its intensity to determine the distance of the second object.

Abstract: A system and method for displaying sonar data are disclosed. In a presently preferred embodiment, each of N channels from a beamformer are separately processed utilizing a pair of passive broadband detection processors such as SCOT processors and SPED processors. The output of each SCOT processor and each SPED processor are scaled, aligned, and then compared. The maximum scaled and aligned output from each pair of processors is selected for input to a bearing time history display.

Abstract: A ground penetrating radar system including a processor for generating audible output signals having discrete frequency components representative of the depth of buried targets. The amplitude of the audible frequency components is representative of the size or mass of the target.

Abstract: A device for non-contractual measurement of the speed of an object moving over a surface comprises a means for radiating a signal of fixed frequency at an angle onto the surface in or against the direction of motion, said angle being variable by the movement of the object, and for receiving a Doppler-shifted signal reflected at the surface. A means is provided for combining a plurality of reflected Doppler-shifted signals, which are received in temporal succession, so as to produce a combined spectrum. The device for non-contractual speed measurement additionally comprises a means for detecting from the combined spectrum the spectral portion having the highest or lowest frequency and exceeding a predetermined signal power, and a means for deducing the speed from the frequency of the detected spectral portion.

Abstract: While successively varying its orientation at specific intervals, a detecting apparatus transmits pulsed radio waves from an antenna (1), and data corresponding to input levels derived from one sweep are written in a primary memory (4). output values obtained in preceding signal processing operation are written in a secondary memory (9). A signal comparator circuit (7) determines current output values based on the input levels of the primary memory (4) and the preceding output values of the secondary memory (9) by reference to a table (8) and writes the current output values thus obtained in the secondary memory (9). The detecting apparatus causes display brilliance or color between a blip exhibiting large fluctuation in received signal strength and a blip exhibiting small fluctuation in received signal strength.

Abstract: An underwater acoustic sensor system for detecting and efficiently displaying data from small, shallow-draft targets at high speeds in shallow or very shallow water. Sonar buoys transmit electrical signals representing sound pressure waves, which are processed to ascertain bearing and signature information for a detected object. A single display having a bearing history area, a frequency history area, and a bearing/frequency area, provide a system operator with efficient correlation between bearing and frequency data.

Abstract: An apparatus and method for scanning a body of water for fish and other underwater articles with a sonar depth finder of a type having a transducer that can transmit an acoustic wave and receive sonar returns on both a narrow acoustic wave beam mode and on a wide acoustic wave beam mode, in which the sonar depth finder repetitively determines the approximate depth of the body of water by repetitively transmitting in the wide beam mode and receiving and displaying the sonar returns from each transmission initially in the wide beam mode and then in the narrow beam mode, with the duration of receiving in the narrow acoustic wave beam mode being a function of the determined depth from a prior transmission.

Abstract: A spoken word-producing detector identifies objects by comparing signatures of detected objects with stored signatures of known objects. When the signatures compare, the detector produces stored word sounds associated with the detected object identifications. An annunciator produces the words from pre-digitized human voice sounds. A screen displays the words.

Abstract: A radar device for use in backing up a vehicle is disclosed herein. A plurality of wave sensors is installed on a rear portion of a vehicle for detecting an obstacle therebehind. A master controller has a plurality of transceiver circuits and a microprocessor connected to the plurality of transceiver circuits. Each transceiver circuit corresponds to one of the plurality of wave sensors. The microprocessor activates the plurality of transceiver circuits to drive the plurality of wave sensors for transmitting and receiving ultrasound wave signals thereby determining the location of the obstacle. A location display device is connected to the master controller for receiving and decoding data related to the location of the obstacle thereby indicating the direction of the obstacle and displaying in numerical form the distance between the obstacle and the vehicle.

Abstract: The depthimeter comprises a heave sensor, a mean path compensator and a combiner. The mean path compensator comprises a ranging device which measures the instantaneous distance of the vehicle from a fixed point on the vehicle to ocean surface as a function of time; a range compensator to compensate for signal dropouts in the ranging devices data, for sensor offset angle, and vehicle pitch and roll, thereby providing a signal that contains the vehicles vertical motion and the vertical motion of the sea surface. A low-pass filter within the mean path compensator eliminates the components of the resulting signal due to the motion of the sea surface and the high frequency components of the vehicle's vertical motion, thereby producing a signal that is the mean path of the vehicle, referenced to mean sea level.

Abstract: A system for sonically probing a seabed comprises at least one row of transducers that each can produce a sonic beam, and a corresponding row of sonic detectors. Each transducer is independently energized to produce a narrow sonic beam, with resulting seabed or subsea echoes being detected to produce one pixel of a display formed by an X-Y array of pixels, before a next transducer is energized and its echoes are detected to produce another pixel of the display. When the system detects a large change in echo amplitude at adjacent seabed locations, then scanning at those locations is accentuated by analysis and by additional sonificiation at different frequencies. The transducers are closely spaced, at a center-to-center distance of typically about 3.5 cm, to provide good horizontal resolution. Each transducer is energized to produce a sonic pulse which, dependent on the application, has a carrier frequency of 0.25 MHz.

Abstract: An ultrasonic distance measuring device for use, for instance, in the building trades, conventionally measures distance by projecting a sonic beam towards the target and detecting the reflection from the target. Also provided is an associated co-axial laser pointer which provides a visual indication of where the sonic beam is pointed. This laser pointer provides a laser beam which illuminates the target. However, the laser beam is not a typical laser beam, but instead is diffracted so that it covers an area at the target approximately the same size and shape as the area covered by the sonic beam. This provides a clear indication to the user that the sonic beam is not a single point beam but instead is possibly reflecting from any one of a number of points on the target.

Abstract: A personal direction finding apparatus for determining the direction to be followed in order to reach a predetermined spot which includes a headset provided with two earphones and a circuit for generating a track error signal. The circuit includes a compass supported on the headset for outputting a heading signal corresponding to the heading of the direction of travel, a receiver for a position location and navigation system outputting a signal for the heading to be followed via one output, and a track error computing circuit.

Abstract: Two digital reflectional signals of different depth ranges are displayed on two divided pictures in a display, whereby the conditions of the water and the bottom in the lake or pond can be detected. Therefore, the fish sonar is suitable for fishing for black bass.

Abstract: A sonar depth sounder device, and a method for processing echo signals reflected from objects within a body of water, utilize a processor, a memory, a display, and a keypad connected to the processor. A transmitter excites a transducer which emits sonar pulses into a body of water, and a receiver receives reflected sonar echo signals. Particularly, signals that have reflected from an object suspended in the water have an intensity, a history time duration, and a depth spreading characteristic. The processor compares one or more of the intensity, history time duration, and depth spreading characteristic of the reflected signals with corresponding sets of parameters stored in memory, which sets of parameters are representative of one or more selected objects, cross-talk noise, and unidentifiable noise.

Abstract: A hand-held LCD game machine is used as a hand-held LCD fish finder, in addition to its original game functions. Instead of a typical ROM game cassette, another device, which includes a cassette portion, a main body, and a float sensor having an ultrasonic transmitter, is inserted into the LCD game machine, so that the topography of the water bottom and the fish in water are displayed on a LCD panel by means of a program ROM having a memory to display the same based on an echo signal issued and received through the ultrasonic transmitter.

Abstract: A cost-effective wideband radar system capable of locating objects, such as reinforcing steel rods, pipes, and air bubbles, objects located behind or within a volume of, e.g., concrete, soil, wood, or air. A sequence of wideband radar pulses are emitted without a carrier from each of two transmit antennas. The system includes a receiver that detects reflected pulse energy (echoes) that result when transmitted pulses encounter a change in material (e.g., an air to metal change or concrete to metal change). These amplitudes of the echoes are visually displayed along with the length of the transmit/echo path for each transmitter. The lengths of the displayed transmit/echo paths are compared to determine whether the system is centered over an object located within or behind a volume, the system being centered over the object when the transmit/echo paths for each transmitter/receiver combination are of equal length.

Abstract: A buoyant transducer assembly which may be attached to a fishing pole for providing signals indicative of objects, such as fish, within the water. The buoyant transducer assembly includes a sonar transducer supported by a float. The float has a central hub defining a downward opened recess for receiving the transducer and diametrically opposing buoyant cells for supporting the float upon the water. The float is positioned upon the water such that a predetermined portion of the float which has a surface area significantly larger than the surface area of the transducer contacts the water, thereby stabilizing the transducer and maintaining the transducer in a predetermined position relative to the body of water.

Abstract: A buoyant transducer assembly which may be attached to a fishing pole for providing signals indicative of objects, such as fish, within the water. The buoyant transducer assembly includes a sonar transducer supported by a float. The float has a central hub defining a downward opened recess for receiving the transducer and diametrically opposing buoyant cells for supporting the float upon the water. The float is positioned upon the water such that a predetermined portion of the float which has a surface area significantly larger than the surface area of the transducer contacts the water, thereby stabilizing the transducer and maintaining the transducer in a predetermined position relative to the body of water.

Abstract: An apparatus for converting the difference frequency between the transmit lse of a sonar and the return or receive signal from a target to a video representation complementing the audio output of the sonar representing the difference frequency. The audio and complementing video signal indicate the presence of the target and its range. The invention converts the audio signal to a frequency spectrogram by means of digital signal processing including a FFT algorithm. The amplitudes of the frequency components of the audio signal are plotted on the video display of the invention. They are color-coded to indicate the amplitude of the audio signal. The frequency of the audio signal is related to the range of an object detected by the sonar. The invention is mobile and easily managed by a diver.

Abstract: A receiver converts an echo received by a transducer to a supersonic echo signal, and a controller measures the depth of obstacles depending on a timing for receiving the supersonic echo signal, obtains an echo level according to quantity of the supersonic echo signal, and determines the condition of the bottom depending on echo levels of a series of supersonic echo signals. A display unit provides a result of detection at a position of corresponding depth scale on a first display area for providing graphic displays of the obstacles as well as the bottom with a depth scale with a gradation or a pattern type corresponding to the echo level. Graphic displays of the echo level are also provided at a position corresponding to depth on a second display area having graphic displays corresponding to depth scale in the first display area.

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: An elongated flexible pole, a shorter flexible connecting member fixedly connected to the outer end of the flexible pole to rotate therewith, an elongated rod fixedly connected to the outer end of the flexible connecting member therewith when the handle end of the pole is rotated, a transducer of a sonar fish finding assembly fixedly connected to the outer end of the elongated rod to rotate therewith, the transducer connected by cable to the signal generating component and monitor of the sonar assembly which is positioned next to the handle end of the pole on the river bank or shoreline, the pole being held at a diagonal extending upwardly and outwardly over the body of water, and an elongated rod extends downwardly into the water on a substantially vertical line, the transducer being submerged below the surface of the water having its transmitting face pointed in a direction parallel to the surface of the water, the transducer and its transmitting face being rotatable on the vertical axis of the elongated ro

Abstract: A system for communicating to a fisherman information relating to fish in water in the vicinity of a fishing lure or hook which is connected to a conventional non-electrically conducting fishing line and which includes a float attached to a conventional non-electrically conducting fishing line with the float being located at or below the water surface. The system also includes a sensor housed in the float for detecting a parameter relating to the fish, the sensor being housed in the float. Also housed in the float are an electronic card and a transmitter for wirelessly transmitting the signal. A power source housed in the float provides electrical energy to the sensor and transmitter. The system also includes a receiver for receiving the signal from the transmitter and a display or other output for presenting information relating to the signal to the fisherman.

Abstract: A display system in a vessel which includes various sensors for detecting various operating and navigating conditions of the vessel and a single display unit for displaying information regarding these conditions. The single display unit is comprised of a fixed display which displays information regarding particular operating and navigating conditions that are frequently monitored. The single display unit also includes a variable display which has a standby state and a display state and which also has a plurality of alternate display modes and a warning display which automatically displays warning information regarding at least one of the conditions that is being sensed when the particular condition is detected to be outside of its predetermined range.

Abstract: The present invention relates to a PPI sonar for horizontally turning a transmitting and receiving transducer emitting and receiving ultrasonic signals in one direction within an azimuthal range in one angular direction and in the reverse angular direction to search the water in a sector form and for having the position of own ship defined at an off-centered point on the screen of an indicator to display underwater conditions in a corresponding wide sectorial display area.

Abstract: A warning device is provided for use in an electric vehicle which includes a frame member and ground engaging wheels operative mounted relative to the frame member. An electric motor is operatively connected to the frame member and the ground engaging wheels for supplying rotational motion to the ground engaging wheels. A switch member is provided for selectively energizing the electric motor. An indicator member is provided for indicating to an operator that the electric vehicle has completed a preparing to start operation. The switch member may be a switch for operatively connecting the electric motor to a source of power. The indicator member may provide a visual display or an audible sound for warning the operator.

Abstract: An improved apparatus and method for finding fish both onshore and offshore, and under a diversity of marine conditions is provided. A specially configured rod and reel combination enables the electrical communication between a sensor float disposed at the remote open end of the rod and a display unit releasably attached to the reel portion disposed opposite of the reel. A transducer is disposed vertically within a foam matrix positioned in a sensor float. Electrical signals are generated within a display unit and then transmitted to the transducer. These signals are conventionally converted into corresponding ultrasonic signals which are directed downward into the environing water. The ultrasonic signals travel until deterred by either fish, an unknown obstacle, or the bottom of the body of water. These signals are then echoed back to the transducer and converted into corresponding electrical signals, for transmission through the conductor cable to the display unit.

Abstract: An improved sonar signal processor and display combining the use of both coherent and incoherent signal processors. In addition to a conventionally used matched filter detection processor, an incoherent signal processor comprising a cross-range energy filter and a down-range energy filter is used. The cross-range energy filter detects objects characterized by a narrow bearing response; whereas the down-range energy filter detects objects characterized by a narrow range response. The detection events resulting from the incoherent signal processor are displayed in a subdued color to prevent distraction from the primary display events and to reduce the false alarm rate by allowing the sonar operator to view events in the context of natural boundaries.

Abstract: A vehicle sensing system includes a data bus, a first microprocessor coupled to the bus and a plurality of sensor modules about a vehicle periphery for detecting the presence of objects within a predetermined range of distances of each of such sensor modules. Each sensor module of the vehicle sensing system includes a transducer, a second microprocessor, coupled between the transducer and the bus, for processing information received from the transducer, and a light emitting diode disposed on an outer surface of a housing for the transducer, coupled to the second microprocessor, for indicating when an object is within the predetermined distance of the sensor module or when the sensor module is faulty. Each sensor module further includes a temperature sensing circuit coupled to the second microprocessor and a bus transceiver for receiving information from the bus and for transmitting information to the bus.

Abstract: The present invention relates to a method and system for generating signals which represent a map that depicts one or more submerged objects within an underwater area; detecting acoustic energy emitted from means carried by a diver within said underwater area, or scanning said area with sonar energy, to develop signals which indicate the location of said diver within said area; and combining said diver location signals with said map representing signals for producing a composite visual display to said diver which shows his location with respect to the location of one or more submerged map objects within said area. A remote station also may be provided at which several of these functions are performed.

Abstract: An echo sounding system includes a acoustic gun which is mounted to the wellhead of a borehole. The acoustic gun produces a acoustic pulse which is transmitted down the borehole. A tubing string is installed in the borehole and it has substantially evenly spaced collars. Fluid is pumped from the borehole, or well, by use of a reciprocating pump driven by a pump rod extending to the surface. Fluid is received from a surrounding formation and collects in the borehole. The acoustic pulse produces reflections when it strikes the tubing collars and the surface of the fluid. A microphone detects the reflections to produce a return signal. This signal is digitized and stored. The digitized signal is processed to detect the rate of the collar reflections and the stored signal is narrowband filtered with a passband filter centered at the rate of receipt of the collars. The data signal is further processed to determine the time of occurrence of the acoustic pulse and the liquid surface reflection.

Abstract: The present invention relates to a method and system for scanning a specified underwater area with sonar energy to generate sonar image signals of a submerged diver and othe objects within said underwater area, processing said sonar image signals at, for example, a remote station such as a surface vessel, whereby information is incorporated with said sonar image signals for designating a route from the starting underwater location of the diver to a particular underwater object, and transmitting said processed signals to an image monitor carried by the diver for providing him with visual directional information to assist him in going from his starting location to the location of the targeted object. Preferably, said directional information includes a route or heading line that the diver can follow on his monitor in moving toward the object.

Abstract: A system for sensing the level of contents in a container is disclosed. A tubular member is vertically disposed in the container and sealed from the contents of the container. A marker located in the tubular member and generating a peripheral polarized magnetic field, is levitated at the height of float means located around the tubular member buoyed on the contents of the container and generating a polarized magnetic field within the tubular member of like polarity beneath the polarized magnetic field of the marker. A depth transducer located at one end of the tubular member forms part of a pulse-echo ranging system which calculates ranges on the basis of a time lag between emission of an ultrasonic signal by the depth transducer and receipt of at least one return echo signal from the marker in order to determine the depth of the marker in the tubular member, and indirectly, the level of contents in the container.

Abstract: A vessel display system that is operative to provide a display both of vehicle operating conditions and extraneous operating conditions. A switching arrangement allows the operator to select either the display of the external condition except during initial operation and when there is an abnormal condition in which case the vehicle running condition is displayed or a condition wherein the vehicle running condition is continuously displayed.

Abstract: The castable fish/depth finder has a display unit, rod and reel, transducer and conductors establishing electrical continuity from the display unit to the rod and reel, and therefrom to the transducer. The conductor from the rod and reel to the transducer additionally functions as mechanical means for conventional casting by an onshore fisherman of the transducer to a particular section of a body of water. The presence of fish in such particular section and the water depth is ascertained and indicia therefor is displayed on a screen of the display unit.