Help needed with diving computer parameters

[Danielk]

I'm about to buy my first diving computer and I'm confused about the Number of Gas Mixes parameter. Some have 1 others have 2 or 3.
What is this parameter stands for, the number of gases I can use in a single dive or a different Nitrox mix each dive (for example if I make 3 dives in a single day then first dive I use air, the second dive I use EAN32 and another one with EAN36 )?

Another thing, when the specification state that the
FO2 is Air, 21% - 100% or Mix 1: Air, 21% - 50%; Mix 2: Air, 21% - 100%
What is the difference between the two parameters (is the Air, 21% - 100% more flexible)?

 

[clownfishsydney]

If you cen set three mixes, you can normally use all three on the same dive or have three set so that you can just pick the right one for the dive. Normally you can set this as well.

Not sure what you mean by the last paragraph.

 

[mala]

its for changing gasses during the dive.

usually the mix 2 and 3 are for deco gasses.

its a intro to tech diving computer.

 

[Danielk]

I'm a recreational diver till now I used only air but now I'm thinking about Nitrox.
I'm not planning on switching gas during the dive but maybe switching gas mixture during a diving day (first dive with EAN32 and a second dive with EAN36)
Is a single gas computer (such as the Suunto vyper be enough?

In the last paragraph I meant that I saw two computers specifications:
Suunto vyper Air, 21% - 50%
Tusa Element II IQ-750 Mix 1: Air, 21% - 50%; Mix 2: Air, 21% - 100%
What is the difference between the two specifications?

 

[rongoodman]

If you want to switch nitrox mixes between dives, you can do so during the surface interval. The multiple gas computers are for switching mixes during the dive for decompression. It doesn't sound like something you need, and if you switch the computer to a different mix by accident and don't actually breath it, your computer's NDL calculations will be wrong.

 

[hroark2112]

The 21%-50 or 100% is the range you can set the FO2. Air is 21% and nitrox is higher.

Have you taken your nitrox class yet??

 

[Danielk]

So I guess a single gas computer will suit me the most (will allow me to witch nitrox mixes between dives).
Am I right?

---------- Post added June 16th, 2013 at 08:50 AM ----------

hroark2112: No, not yet. I'm currently looking for a computer that I will able to use after I will become Nitrox certified.

 

[hroark2112]

A single gas computer should be fine.

Befire you pull the trigger on your purchase, talk to your instructor about the computers you're looking at buying. Some are very easy to set and understand. Some aren't as intuitive. My wife uses a Cressi Leonardo and loves it. Easy to set & understand, gives her everything she needs. I use an Aeris Elite T3 as my primary computer and a Genesis ReactPro as my backup. Both are easy to set & use but I like the wrist mounted T3 better.


Buy the computer before your class too, and learn to set it to air and nitrox in class.

 

[DevonDiver]

Mixed gas 'recreational' computers are kinda pointless IMHO. No-deco divers will never use the function (subsequent gasses are for deco mixes). Deco divers will invariably want something with substantially more 'oomph' in respect to algorithm flexibility.

 

[Danielk]

Thanks,

The T3 Elite was my first choice (price, features and recommendations) but then I found out that it was discontinued and it is too liberal for me.
So in the category of wireless AI computer I choose the Oceanic Atom 3.1.
Form the non AI wrist computer I have an endless list of models to choose from:
Cressi (Archimede 2, Leonardo and GIOTTO)
Mares (M2, Nemo Wide, Puck Wrist and Puck Pro)
Oceanic (GEO and GEO 2)
Suunto (viper and zoop)
Tusa (Element II IQ-750)
Scubapro (UWATEC Aladin Tec 2G )
So if you have any comments on one of the above models, I will appreciate it.
But mine main problem is to decide whether to buy an AI or a non AI wrist computer. Or in other words, will I be able to depend on this type of a computer and not having a backup SPG (if I will need a backup SPG, buying AI computer is pointless, IMO).