Hoseless AI and electrical signals???

Let me start off by saying I am a newbie, which means I have to rely on my LDS and this site for info. I was looking into a hoseless AI computer (Vytec), and my LDS said he would never dive with one. His reasoning was that the transmitter emits an electrical signal that could attract sharks. Since I'm on the West Coast, great whites are around. He mentioned that he was on a dive, and one of the other divers was attacked by a shark (and lived!!), and that he was wearing a wireless transmitter unit.

Is there any truth to this? I don't have any reason to doubt him since he will gladly sell me the more expensive unit with the transmitter. Has anyone else heard of this?, or have any experience with it? I just want all of the concerns answered before my purchase.

Thanks,

magic_johnson
Go Lakers!!!!!

I've heard of a few incidents involving scooters, but never an AI computer. Interesting theory though.

it sounds like a big ole load of bull to me. I can't understand why he would tell you that stuff, I believe there is more to it than justan AI computer. Besides, I was a Bahamas trip just last year in April with some friends who both dive with AI computers and we dove 3 or 4 days with sharks in the water and they were never attacked, I think the sharks pretty much ignored them.

Rich :mean:

A hoseless AI computer does not use an "electrical" signal, it uses an electromagnetic signal, IE: radio!

This theory that it attracts sharks, or any other species of creature that live in water is best left to the imaginations of "B" grade Sci-Fi movie writers.

In short form the answer to will it attract sharks is, no. In long form, Bwwaahhhaahahahahahaha. :rofL:

All electrical devices create electromagnetic signals that could, in theory, be detected by sharks. We know only bits and pieces about the Ampullae of Lorenzini, the electrical receptors used by sharks -- but we do know roughly how sensitve they are:

Sharks have demonstrated the ability to sense a mamallian heartbeat some nine feet away only by sensing the RF energy emitted by the electrical current moving through nerves in the heart.

Fear not, however, as sharks apparently use their sophisticated equipment for navigation more than for hunting. Despite the ignorance of folks like pt40fathoms and his friends, the "B" grade Sci-Fi movie writers, your hoseless AI computer almost certainly is detectable by a shark -- but probably only in very close proximity. He'll smell you long before he detects your AI computer.

In short, it's an interesting proposition, but I wouldn't worry too much about a hoseless computer attracting sharks.

However, hoseless AI computers have much more sinister qualities, which you should be much more concerned about:

1) They are unnecessary.
2) They are overly complicated.
3) They require batteries.
4) They're expensive.
5) They're expensive to repair.
6) They WILL break down on you.

AI computers are a solution looking for a problem. Hoseless AI computers are just plain silliness. As you're a new diver, I would strongly recommend steering clear of all AI computers. In fact, I'd venture one step further and suggest that a bottom timer and a good set of tables will do you better in the long run than any sort of computer. If you are determined to get a computer, though, get a wrist-mountable, non-AI style, nitrox capable model. Take the money you save and apply it to more training, which is indisputably the wisest investment you can make as a diver.

- Warren

You are welcome to your opinions Warren, but in the interests of providing magic with balanced input:

Originally posted by VTWarrenG
However, hoseless AI computers have much more sinister qualities, which you should be much more concerned about:

1) They are unnecessary.
2) They are overly complicated.
3) They require batteries.
4) They're expensive.
5) They're expensive to repair.
6) They WILL break down on you.

Click to expand...

Sinister???

1) Pure opinion
2) Overly complicated to use?
3) So do what most people use for bottom timers
4) More expensive, yes, but not necessarily too expensive, depends on the size of your wallet
5) No more than any other dive computer
6) Now that's just toooo much bait

"AI computers are a solution looking for a problem."

Actually, I would say that the question "how does my computer know exactly what my Nitrogen intake is?", is a fairly crucial question looking for an answer.

"Hoseless AI computers are just plain silliness."

Unnecessary, maybe, but silly's going a bit too far [IMHO].

Mark.

Mark,

Your post seems to indicate you think your opinion is more relevant than mine. You criticize me for stating "pure opinion" and then follow up by posting your own "pure opinion." You can't criticize one opinion with another. Get it straight.

1) They are unnecessary. A mechanical SPG and a bottom timer or other computer-type device provide all the same information, in virtually the same format, but provide none of the possible failure points of a hoseless AI computer. This is the definition of being unnecessary -- providing no additional features, while providing several additional disadvantages.

2) They are overly complicated. They have additional electronics not found in conventional computers or bottom timers.

3) They require batteries. My mechanical SPG does not require batteries. I was not intending to say that bottom timers do not require batteries -- only that SPG's do not.

4) They are expensive. I assume you understand implication. Of course I was implying that they are more expensive than their simpler cousins. This is not an argument.

5) They are more expensive to repair. Ask around. AI computers, and particularly hoseless AI computers, are more expensive to repair than their simpler cousins.

6) They WILL break down on you. The failure rate of hoseless AI computers is certainly higher than that of mechanical SPG's.

"How does my computer know exactly what my Nitrogen intake is?" It doesn't. This is why I do not use computers.

And I certainly feel they are silly, and that's my opinion. You may have your own opinion, but don't make the mistake of trying to convince me that your opinion (they aren't silly) is more valuable than my opinion (they are).

- Warren

VTWarrenG, could you be so kind as to provide proof of the claims you have made regarding sharks and High Frequency EM radiation. I am NOT asking for web site info, I am asking for papers published on the subject that have been defended in the peer review and stood the test.

I patiently await your response, while I watch Plan 9 from Outer Space.

pt40,

Typical response.

You expect me to go to the Stanford library, look up papers in biological journals on the sensitivity spectra of the ampullae of lorenzini, scan them, and post them here just to prove something to you? And since I have neither the time or the inclination to do such, you're surely going to assume a) such papers don't exist and b) you've won the argument.

Listen, if you don't believe **** stinks, that's hardly relevant to me.

- Warren

Warren,

I was merely flipping the coin over, as I said, to provide balance. Perhaps I should have left the "pure" out - it wasn't meant to indicate criticism of your opinion itself, but rather a jab at the way it was presented.

And I certainly feel they are silly, and that's my opinion. You may have your own opinion, but don't make the mistake of trying to convince me that your opinion (they aren't silly) is more valuable than my opinion (they are).

Addressing your last paragraph here, so that I can assure you up front - I don't have the slightest interest in convincing you of anything. My interest is in providing another viewpoint.

1) They are unnecessary. A mechanical SPG and a bottom timer or other computer-type device provide all the same information, in virtually the same format, but provide none of the possible failure points of a hoseless AI computer. This is the definition of being unnecessary -- providing no additional features, while providing several additional disadvantages.

The additional feature is having AI on your arm and not on a console. The downside (not "several") is a slightly higher possibility of failure compared to a hose (within acceptable limits with modern versions, IMO).

2) They are overly complicated. They have additional electronics not found in conventional computers or bottom timers.

That makes them more complicated, but not necessarily "overly" complicated.

3) They require batteries. My mechanical SPG does not require batteries. I was not intending to say that bottom timers do not require batteries -- only that SPG's do not.

A very valid point, although it's about underwater electronics in general and not only hoseless computers.

5) They are more expensive to repair. Ask around. AI computers, and particularly hoseless AI computers, are more expensive to repair than their simpler cousins.

Could very well be, but I guess it depends on who is doing the repairing and what has to be repaired. I gotta say though, for me, dive computers belong in a certain category of electronics, along with digital cameras and laptop computers (sometimes)... if it breaks and it's out of warranty, use it as a door-stop

6) They WILL break down on you. The failure rate of hoseless AI computers is certainly higher than that of mechanical SPG's.

C'mon Warren, this is a stretch. A probable (coz we don't really have any numbers) higher failure rate (of hoseless computers specifically) does not translate into "they WILL break on you".

Agree to disagree?

Mark.