Cochran computers

[No Fish]

Thanks for the info. Is there anywhere online I can buy one? There isn't a dealer within a reasonable distance of me (or even within an unreasonable distance!). I did a Google search but nothing there...

thanks!

PM me

PS You don't need a coin. Any metal will do.

 

[Mark Vlahos]

You can get one from Tech Diving Limited.

As far as setting the conservatism is concerned there are 50 different levels. level 0 is the base level and this is the most liberal level there is. With each increase of 1 the computer makes its calculations for your nitrogen loading based on being one percent lower than you actually are. If you set the conservatism to 10 and make a 50 foot dive it will make all of your nitrogen loading calculations as if you were at 55 feet. This may not be the best way to do it but it is a method I can understand. Please note, the conservatism will only change your depth for nitrogen calculations, if you are diving NITROX all of your oxygen calculations will be based on your actual depth NOT any percent deeper. I am only familiar with the standard version of the computer, I do not know how the helium computer operates.

With the conservatism set to 0 it is quite liberal at shallow depths and slightly conservative at the limits of recreational diving. The cross over point seems to be around 80 or 90 feet.

I have a Cochran Gemini and I keep the conservatism set around 15 or 20 most of the time.

The Commander is capable of being a two gas computer on open circuit SCUBA. If you get it in its most basic version it is air only, it is also available as a one NITROX computer (1FO2) or a two NITROX gas computer (2FO2).

The display is large and easy to read. It has two information screens while you are diving. If you either tap the screen of shake your wrist violently you will turn on the backlight and change the display to the other screen. The amount of time the light stays on is adjustable. The three touch contacts can sense the difference in resistance between your fingers, fresh and salt water, and a piece of metal. When you are on the surface it uses this difference to allow you to change some of the settings in the computer, you really need to spend some time with the computer and the manual to figure out how to change the settings.

I would reccomend getting the "Analyst" software for your computer at home so you can download the dives and change some of the settings. Many of the user variable settings are available to you on the Commander directly but there are many more that are only available for you to change if you use the Analyst interface.

The computer is quite nice but it can be a little confusing at first, it will provide you with a lot of information. You really should spend time reading the manual before you decide to purchase one. You can download the manual from the Cochran website for free, it is worth the read.

Enjoy,

Mark Vlahos

 

[teknitroxdiver]

PM sent

Wow lots of info, thanks Mark

 

[Vie]

Is there anywhere online I can buy one?

You can actually buy directly from Cochran—I did that as I was living in RI at the time and there were no dealers (you can probably get a better price from a dealer though).

These are the available configuration for

Commander:

Air Only
One Mix Nitrox - 1 FO2
Two Mix Nitrox - 2 FO2
One Mix Nitrox Switchable to One PO2 - 1 FO2 / 1 PO2
Two Mix Nitrox Switchable to Two PO2 - 2 FO2 / 2 PO2

Commander EMC-20H:

Air Only
One Mix Nitrox - 1 FO2
Two Mix Nitrox - 2 FO2
One Mix Nitrox Switchable to One PO2 - 1 FO2 / 1 PO2
Two Mix Nitrox Switchable to Two PO2 - 2 FO2 / 2 PO2
One Mix Nitrox + Helium (One Mix Trimix or Heliox) - 1 FO2 + He
Two Mix Nitrox + Helium (Two Mix Trimix or Heliox )- 2 FO2 + He
One Mix Nitrox + Helium (One Mix Trimix or Heliox) Switchable to One PO2 + Helium (Trimix Diluent) - 1 FO2 / 1 PO2 + He
Two Mix Nitrox + Helium (Two Mix Trimix or Heliox) Switchable to Two PO2 + Helium (Trimix Diluent) - 2 FO2 / 2 PO2 + He

There are eight colours to choose from.

 

[teknitroxdiver]

I've haven't been able to find any prices on the Cochran page, and the Techdivinglimited.com page seems to be down today, maybe tomorrow it will be back up.

For no-deco nitrox diving and possibly basic deco in the future, which would you guys pick: Nitek Duo or Cochran Commander w/ 1 nitrox mix?

(Edited to change Nitek Plus to Nitek Duo; my typo)

 

[Vie]

E-mail Cochran for prices.

sales@divecochran.com

IMHO I definitely go with the Cochran Commander. If you are considering Dive Rite, the NiTek Duo seems like a better deal than the NiTek Plus.

 

[Mark Vlahos]

I've haven't been able to find any prices on the Cochran page, and the Techdivinglimited.com page seems to be down today, maybe tomorrow it will be back up.

For no-deco nitrox diving and possibly basic deco in the future, which would you guys pick: Nitek Plus or Cochran Commander w/ 1 nitrox mix?

Earlier in this thread you expressed a curiosity about the size of the characters on the screen, the Cochran will have much larger displayed information. The NiTek is essentially the size of a wristwatch, this is not necessarily a bad thing, just somthing to consider.

The NitTek has a separate guage mode, the Cochran does not. The cochran will continue to display your run time, depth and all of the rest of its information even if you violate it. It will not "lock out".

You are attempting to compare an apple and an orange. The computers do essentially the same thing, that is provide you with appropriate information for diving, but do it in different ways. This is essentially the same problem every diver has when trying to decide between two different dive computers.

If your long term goal is to purchase a dive computer and use it for planned decompression divnig you will probably find that in your class you will need a depth guage and two TIMING DEVICES and you will dive tables. Either of these computers will suffice as a depth guage and timing device. If you plan on using a computer for computer based decompression diving you will probably want to have TWO of them. If that is your goal, you might consider both of these computers as they will suffice, and if you have two different computer models you will not run into a possible programming error in either version of the software.

Please be aware, if your plan is to use a dive computer for computer based decompression diving you may find that having a THREE gas computer is a better choice. MIX one for your backgas, MIX two for your first decompression gas, and MIX three for Oxygen. This model will shorten your decompression time underwater and certainly requires training and additional equipment. Either of the computers you are considering will work as sophisticated "bottom timers" for this type of diving, but neither will actually perform all of the calculations needed for three gas diving.

If you want to buy a computer before you begin the training for intentional decompression diving I think it would be a mistake, if that is the style of diving this computer would be used for. If you want a computer to use on recreational diving that can get you out of an unintended decompression situation you will most likely only have one gas available to you and either of these computers can handle that situation. There are many other computers on the market that can also do this. No mater what type of computer any diver uses it does not excuse entering unplanned decompression; only good dive planning and execution can solve this. If your computer tells you that you need to stay at a decompression stop, but you are out of breathing gas, you are pretty much screwed. The computer will not put more gas in your tank. Safe decompression diving requires proper planning and gas management.

I hope my long reply helps. Again if you want a computer try to get one that is appropriate for the type of diving you are doing. If you choose the Cochran give Joel at Tech Diving Limited a phone call for his best price, he can only post list price on the web, but he can and does sell for less.

Lots to consider, good luck.

Mark Vlahos

 

[retnug]

I also dive the commander 2 gas. I really like it. Easy to read and use. regarding the coin thing. What I did was ziptie a SS washer to the band using two small zipties throught the buckle holes. Make sure the washer can reach the contacts from where it is connected. Never have had to search for a coin.

 

[Mark Vlahos]

I also dive the commander 2 gas. I really like it. Easy to read and use. regarding the coin thing. What I did was ziptie a SS washer to the band using two small zipties throught the buckle holes. Make sure the washer can reach the contacts from where it is connected. Never have had to search for a coin.

I have used the blunt tip of my dive knife (I don't really like this method though and, for other reasons, have replaced my knife with a line cutter), my low pressure inflator hose quick release fitting, and the rounded end of my "EMT" shears at various times when I am on a dive boat. At home I use a quarter.

Mark Vlahos

 

[teknitroxdiver]

Thanks for the added info, although I think I caused Mark a lot of unneeded typing due to my typo: I meant Nitek Duo instead of the Plus. (me and my sister had just had a discussion about computers so I had a bunch of them on my mind....)

Looks like I'm leaning toward the Cochran now.