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Name: brian j billisitz
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993

I would like to know how to construct a underwater detection unit to catch crabs using a pot or some other device.

I am not sure that you want detection or trapping ability. If a trap has an easy way in but no obvious way out and can allow the smell of bait to get out, you will catch lots of crabs. Look up crab traps in fishing or other books.

samuel p bowen might be neat to design a way that a crab fisherperson could tell whether the bait had been taken and/or that a crab (or crabs) had been trapped....some kind of signal or something. I think most commercial fishers just put out all their pots, and then pull them all up and check them. If there was some kind of cheap, reliable way to tell what the "state" of the trap was without having to pull it up, it might save a lot of toil and time. But do I have any ideas? No....


Radar does not work well underwater, because radio frequencies (the R in RADAR) do not get very far before being absorbed. (Kind of like trying to see through a wall, the light does not get very far.) There are many books on sonar, try any library. There are other ways to detect things under water depending on what it is you are trying to detect. For a submarine, they can detect the iron by its effect on a magnetic. If it is something big, you can also look for a wake if it is moving.

daniel n koury jr

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