JPS6449988A - Fish finder - Google Patents

Fish finder

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Publication number
JPS6449988A
JPS6449988A JP20802487A JP20802487A JPS6449988A JP S6449988 A JPS6449988 A JP S6449988A JP 20802487 A JP20802487 A JP 20802487A JP 20802487 A JP20802487 A JP 20802487A JP S6449988 A JPS6449988 A JP S6449988A
Authority
JP
Japan
Prior art keywords
fish
school
difference
current
superconductor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP20802487A
Other languages
Japanese (ja)
Inventor
Keisuke Honda
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Honda Electronics Co Ltd
Original Assignee
Honda Electronics Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Honda Electronics Co Ltd filed Critical Honda Electronics Co Ltd
Priority to JP20802487A priority Critical patent/JPS6449988A/en
Publication of JPS6449988A publication Critical patent/JPS6449988A/en
Pending legal-status Critical Current

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  • Measuring Magnetic Variables (AREA)

Abstract

PURPOSE:To securely detect a school of fish by charging gaseous nitrogen in a double container and cooling a superconductor, and calculating the difference of the output of the superconductor and detecting only fine magnetism produced by the school of fish. CONSTITUTION:The superconductive element 4 is mounted on a frame body 3 in the double container 2, which is then filled with the gaseous nitrogen. A magnetic detector 9 is towed by a ship 10 on the seal 11 at a certain distance. A current is supplied from a DC power source 12 to the superconductive elements 4a and 4b of the towed device 9 and ammeter 13a and 13b detect variation of the current. The current values of ammeters 13a and 13b are converted by A/D converters 14a and 14b into digital signals, which are inputted to a detecting circuit 15. The circuit calculates the difference between the digital signals and variation of the difference is displayed on a display device 16. Consequently, the school of fish is securely detected.
JP20802487A 1987-08-20 1987-08-20 Fish finder Pending JPS6449988A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP20802487A JPS6449988A (en) 1987-08-20 1987-08-20 Fish finder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP20802487A JPS6449988A (en) 1987-08-20 1987-08-20 Fish finder

Publications (1)

Publication Number Publication Date
JPS6449988A true JPS6449988A (en) 1989-02-27

Family

ID=16549410

Family Applications (1)

Application Number Title Priority Date Filing Date
JP20802487A Pending JPS6449988A (en) 1987-08-20 1987-08-20 Fish finder

Country Status (1)

Country Link
JP (1) JPS6449988A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5126655A (en) * 1988-10-04 1992-06-30 Sharp Kabushiki Kaisha Apparatus for observing a superconductive phenomenon in a superconductor
JP2016048169A (en) * 2014-08-27 2016-04-07 公益財団法人国際超電導産業技術研究センター Vibration sensor and vibration sensing system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5126655A (en) * 1988-10-04 1992-06-30 Sharp Kabushiki Kaisha Apparatus for observing a superconductive phenomenon in a superconductor
JP2016048169A (en) * 2014-08-27 2016-04-07 公益財団法人国際超電導産業技術研究センター Vibration sensor and vibration sensing system

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