Advice needed for Suunto Vyper: switching from gauge to air modus impossible?

[supervisor]

Hi all,

its me again....

just got a question about the suunto vyper. I am very interested in buying this computer, because it has a gauge mode and nitrox mode.

Currently I do not have EAN certificates and I am not going to learn nitrox diving in the next 2 years, but it would be nice if I had a nitrox compatible computer at the moment for future use.

At this moment i am diving with a Mares Tutor, which has no gauge mode or nitrox mode. I often do snorkle around the beach and I think it would be handy to have a bottom timer during snorkling?

So I am deciding to sell my tutor and buy the vyper because:
-it uses a RBGM model
-it has gauge mode
-it has nitrox mode
-it has backlight
-other great stuff

i think the vyper is a great computer BUT:
-on suunto.com I read that it is not possible to switch from gauge mode to air or nitrox mode, if gauge mode is used for more than 5 minutes.

does this mean, that I can not use this computer to snorkle around in the morning and than do a dive in the afternoon?

is there somekind of workaround? Even my tutor has the possibility to erase the residual nitrogen memory!

Can anyone advice me?


;-0

 

[NJdiver85]

A computer that allows the user to erase the residual nitrogen memory could prove very dangerous. Anyway, if you are just snorkeling, why not keep the computer in Air mode? You would get the same information as in Guage mode, plus you could dive the unit in the same day. I doubt it would charge you any meaningful nitrogen loading for a few shallow surface dives?

 

[supervisor]

I think that's a great idea!

But here is the thing that I did not tell you:

if I sell my tutor now, I get 1/3 of the price of a vyper. so selling my tutor now will get me a bit closer to the vyper than selling it after 2 years.

But on the other hand in about 2 years there are probably better nitrox computers than the vyper OR the vyper has become much cheaper.

Anyway, I am going to test-snorkle my tutor this weekend!

 

[MechDiver]

A better question would be why in heavens name you think you need a computer to snorkle. And why it would be in gauge mode. And why you couldn't just use gauge mode to dive.

I guess that's 3 questions.

Geez.

 

[nitroxbabe]

I don't understand why you'd use a computer to snorkel, either.

However I own a Vyper and can tell you how it is intended to be used with nitrox/air.

You set the computer to nitrox mode. You leave it there. You then set your O2 percentage before every dive: if it's air, you set it for 21%. Etc. Etc. Etc.

It's really very easy. And yes, it does remember your residual O2 exposure.

Just a note: I have recently realized that the Suunto computers are VERY conservative. If you exceed your no-deco times, you are given unnecessarily long stops. My buddy & I conducted an experiment to test this: he strapped a Vyper to his Commander. The Commander asked him to do a 3-minute stop. The Vyper was somewhere around 18-20 minutes. The Vyper then locked up for 48 hours when it was not satisfied.

I'm getting ready to get rid of my Suunto and get a computer that works better for the kind of diving I'm doing. Don't know what you are planning, but be warned, it used "punitive algorithms" according to a friend of mine.

 

[jonnythan]

nitroxbabe once bubbled...
I don't understand why you'd use a computer to snorkel, either.

However I own a Vyper and can tell you how it is intended to be used with nitrox/air.

You set the computer to nitrox mode. You leave it there. You then set your O2 percentage before every dive: if it's air, you set it for 21%. Etc. Etc. Etc.

It's really very easy. And yes, it does remember your residual O2 exposure.

Just a note: I have recently realized that the Suunto computers are VERY conservative. If you exceed your no-deco times, you are given unnecessarily long stops. My buddy & I conducted an experiment to test this: he strapped a Vyper to his Commander. The Commander asked him to do a 3-minute stop. The Vyper was somewhere around 18-20 minutes. The Vyper then locked up for 48 hours when it was not satisfied.

I'm getting ready to get rid of my Suunto and get a computer that works better for the kind of diving I'm doing. Don't know what you are planning, but be warned, it used "punitive algorithms" according to a friend of mine.

From what I've read, the Suunto computers are very forgiving of "good" dive profiles and penalize you heavily for poor technique, exceeding 30 fpm ascent, and bouncing/poor buoyancy during your bottom time. That may be the punitive algorithm.... sounds like a fantastic idea if you ask me. All that stuff contributes to rapid bubble formation, and once they're there....

I've never used one, I don't know... but it's something to think about and kinda makes sense to me. And I don't really know much about bubble formation or anything, but.. it makes sense to me, too

 

[nitroxbabe]

The Suunto computer will "penalize" you for exceeding your previous dive depth by a mere 1 foot. I've seen it. I don't know the formulas, but I've seen it.

BTW I don't have the habit of "bouncing", ascending quickly, or diving unsound profiles.

The person who told me about the "punitive" algorithms is a new friend of mine who was recently published in Immersed. He's a very intelligent guy, a mathematician, and a technical diver who knows and dives decompression theory. I think he's credible.

There is obviously significant differences in the way different computers calculate decompression obligations: this is quite obvious in the test of the Cochran Commander vs the Suunto, and was further accented when I presented the data to my tech diver friend who agreed that the obligation was excessive.

I've dove alongside my friend with the Commander (and yes of course there are always going to be minor differences in our profiles, so let's not even go there). My computer gave me a deco obligation, his did not. That's the facts, "fantastic" or not.

 

[MechDiver]

nitroxbabe once bubbled...

Just a note: I have recently realized that the Suunto computers are VERY conservative. If you exceed your no-deco times, you are given unnecessarily long stops.

I'm getting ready to get rid of my Suunto and get a computer that works better for the kind of diving I'm doing. Don't know what you are planning, but be warned, it used "punitive algorithms" according to a friend of mine.

I agree. I was looking very strongly at the Vytec as a nitrox computer that would stand some mild deco, and trimix b/t in gauge mode. Running their simulator software, it was very apparent not only was the Vytec not a deco compatible computer, it was too conservative for even mildly aggressive rec diving. Too bad as it has some very good features.

MD

 

[MechDiver]

jonnythan once bubbled...


From what I've read, the Suunto computers are very forgiving of "good" dive profiles and penalize you heavily for poor technique

Don't agree. The Suunto definition of "good" technique is what they want you to do, and exactly how they want you to do it. The computer is much too conservative for anything other than advanced snorkeling IMO.

MD

 

[JRRKAR]

To answer your basic question.....I have a Cobra computer, and if you make a dive in Nitrox mode (and I assume the same in gauge mode) you cannot switch back to air mode until your "No Fly" time has expired. And if you want to make a repetetive dive on air, before your "No Fly" time has expired, you just keep the computer in Nitrox mode and set the O2 at 21%.

I agree with the others that the Suunto computers are very conservative especially on multiple dives the same day with minimal surface interval time. Other than that I really like the computer. Had I know the conservatie nature of Suunto computers before I bought it, I probably would of looked harder at other computers. but still would of considered Suunto.