Underwater electrical potential detection system

A system of recording the passage of a vessel through a harbor entrance comprising, a pair of channels arranged across the shipping lane along which the vessel will traverse when entering the harbor, a first of said channels comprising a first plurality of equally spaced devices and a second plurality of similar devices spaced midway between said first devices respectively, the second of said channels comprising third pluralities of and fourth pluralities of similar devices alternately spaced midway between said first and second devices respectively, said first and second devices and said third and fourth devices being adapted to produce first and second signals respectively indicative of the electrical potential of the vessel as the vessel passes thereover, a pair of means for receiving the signals from said channels respectively, means responsive to said signals for adding the signals together, and means responsive to said added signals for recording the sum of the signals.

A system for recording the passage of a vessel through a harbor entrance comprising, in combination, means including a first plurality of equally spaced electrodes in communication with the surrounding water and arranged along the bed of the entrance of the harbor transversely of the path of travel of the vessel for receiving a signal portion from said vessel when the vessel passes thereover, means including a second plurality of electrodes in communication with the surrounding water and spaced midway between said first electrodes for receiving a signal portion complementary to said first signal portion and together therewith comprising a first signal received from said vessel when the vessel passes over said electrodes, means including a third and fourth plurality of electrodes in communication with the surrounding water and alternately spaced midway between the first and second electrodes respectively for receiving complementary signal portions comprising a second signal received from the vessel when the vessel passes thereover, means for adding said first and second signals together, and means for recording the sum of the first and second signals.

A system for recording the passage of a vessel through a harbor entrance comprising, a pair of electrode channels arranged on the bed of the water transversely of the shipping lane of the harbor entrance, the first of said channels having a plurality of equally spaced electrodes in communication with the surrounding water and having each alternate electrode electrically connected together in parallel to one side of the channel, the remaining electrodes of said first channel being electrically connected together in parallel to the other side thereof, the second of said channels having a plurality of electrodes in communication with the surrounding water and respectively disposed midway between the electrodes of the first channel, each alternate electrode of said second channel being electrically connected together in parallel and to one side thereof, the remaining electrodes of the second channel being electrically connected together in parallel and to the other side of the channel, means connected to the output of said channels for adding signals detected thereby and indicative of the strength of the electric field of the vessel at said electrodes as the vessel passes thereover, and means responsive to said added signals for producing a recording of the variations therein.

Apparatus for recording the passage of a vessel through a harbor entrance comprising, in combination, a pair of channels arranged on the bed of the water at the harbor entrance transversely of the path of travel of the vessel, the first channel having a plurality of mutually aligned and equally spaced electrodes in communication with the surrounding water, each alternate electrode being electrically connected in parallel, the remaining electrodes being electrically connected in parallel, the second channel having a plurality of electrodes in communication with the surrounding water and arranged midway between the electrodes of the first channel with each alternate electrode of the second channel being electrically connected in parallel, the remaining electrodes of the second channel being electrically connected in parallel, means for receiving a signal from each channel individual thereto as a vessel traverses said electrodes, and means for recording the sum of said signals.

Apparatus for recording the passage of a vessel through a harbor entrance comprising, in combination, a first channel comprising a plurality of mutually aligned and equally spaced electrodes submerged within the water across the harbor entrance, each alternate electrode being electrically connected together and the remaining electrodes being electrically connected together, a second channel comprising a plurality of electrodes submerged within the water and arranged in alignment with and midway between the electrodes of the first channel, each alternate electrode of the second channel being electrically connected together and the remaining electrodes of the second channel being electrically connected together, means in said channels and operatively connected to said electrodes individual thereto for receiving a pair of signals in said first and second channels respectively in response to the passage of the vessel over said electrodes, means for separately amplifying and rectifying said signals to produce D.C. signals of the same polarity, and means for adding and recording the sum of the D.C. signals.

Apparatus for recording the passage of a vessel through a harbor entrance comprising, in combination, a cable having a plurality of conductors therein and arranged on the bed of the water at the harbor entrance transversely of the path of travel of the vessel, a first plurality of equally spaced electrodes arranged in communication with the surrounding water and electrically connected to a first conductor of said cable, a second plurality of electrodes spaced midway between said first electrodes and arranged in communication with the surrounding water and electrically connected to a second conductor of said cable, a third and fourth plurality of electrodes arranged in communication with the surrounding water and alternately spaced midway between said first and second electrodes respectively, said third and fourth electrodes being electrically connected to a third and fourth conductor respectively of said cable, means operatively connected to said first and second conductors for receiving a first response signal as the vessel traverses said first and second electrodes, means operatively connected to said third and fourth conductors for simultaneously receiving a second response signal as the vessel traverses said third and fourth electrodes, means for adding said first and second response signals together, and means for recording the sum of said response signals.