Back up dive computer

[Tortuga68]

Just make sure it's not a quartz watch

 

[SEMO Scuba]

I guess I am one of the weird few that have 2 computers. One is a hose mounted air integrated console type, and the other is a low end wrist mount. I take both when I am on dive trips with repetitive dives on multiple days.

If my main computer dies:
I don't have to thumb the dive, but will if I can't monitor air supply.
I will have a working unit for ascent and safety stop
I will not have to sit out the remainder of an afternoon because I lost my dive profile

It is comforting to have a backup, and my backup only cost $149.

 

[EastTNDiver]

I think we can take 'wear' as meaning 'take it along'... although personally I would wear it, if you do have a failure you don't have to fiddle around/thumb the dive, plus you can make sure you keep both of them out of deco - and lastly it's interesting to see/know what the differences (if any) are in depth reading, NDL, nitrogen loading & other data

Might be worth mentioning here that if you use EAN you should set both computers, if you choose to use two, to the correct mix or your backup isn't going to track your nitrogen loading correctly

Agree about your second point, since there are other advantages to using the same brand and/or model - same battery kit, screen protector, strap/mount etc not to mention not having to remember two sets of operating instructions, display layouts, warning sounds/symbols and so on

Just offering the OP an option he may not have thought about. Personally, I don't like wearing two computers on my arms for rec dives, and have never actually needed to utilize a backup. Thumbing a single dive isn't that big a deal for me, and retrieving my backup out of my pocket is even less an issue.

Excellent point on making sure both computers are set to the same mix.

 

[Amphiprion]

I don't find it necessary for recreational diving. However, it is always good to have a second instrument for depth and time if your computer dies on the first dive.

For technical, I think it is very important (a second instrument for depth and time, not necessarily a computer). I had my primary computer die at the end of the deepest part of my dive and had to switch to my tables and backup computer. A complete murphy moment.

 

[RTee]

Pretty soon, I will start doing the dives of my Adv Nitrox and Deco course. Therefore, I am planning to buy in the very near future a second computer that will be multi-gas and gas switchable. The intent will still be to cut tables based on planning software. My present computer will be used on depth gauge mode as a back-up. Right now, I only use one computer and have a watch and tables as a back-up. My get out of jail card...my diving partner as immediate back-up as we always dive the same profile on diving trips using the same mixture. So in fact she is wearing my back-up and me... hers.

If we follow the same logic I should be also diving with a second tank and alternate/dual bladder........ooooops already there.

 

[Jdillardtiger]

Thanks for all the info.

 

[drdaddy]

I always dive with 2 computers. One on each wrist. The reason is that I dive weekly with the same configuration that I dive when it is a special trip. I want familiarity with my equipment. You've all read this in your training - if you are going to change any of your dive gear, practice with it.

I actually enjoy watching the little differences in each of my computers. One is a Oceanic Veo 250, the other is a Suunto Vytec (I don't do airless).

When doing a number of consecutive boat dives, I don't have to worry about my computer dying and having to get out the charts. But the reality is, that I've already planned my dives before hand and know I will not go beyond no decompression dive limits. But here's also the real truth. I've never had a boat or outfitter/dive group question me about the read on my computer. They have already timed/calculated depth and NDDL for the series dives they are taking us out on. Therefore, they give us enough surface interval time that no one on the boat will reach NDDL anyway.

But since I have 2 computers, it would just seem like waste not to wear it. But here's another confession - I also have a Suunto Vyper - I just resist wearing it as well.

The simple answer is, if you are diving and have 2 computers, wear them. And it never hurts to have a spare.

P.S. Please don't ask about carrying a spare knife - then I'll have to open up all my pockets and count them!

 

[AndrewA]

When I started to dive I used tables for my first 40 dives then I bought my first computer (Suunto Vyper) but contiued to use tables until I had confidence in the computer (or rather my ability to use it!). Then I started to use the computer for both diving and planning but carried back-up tables on the dive. Later I added a wristwatch /computer from the same manufacturer. I still use this set up for all my recreational dives(including the waterproof tables I carry with my wet notes)

 

[mjatkins]

I wear an air integrated (D-9) computer on my wrist, as well as having a more liberal oceanic in my console. I use the more conservative D-9 as my primary, and the Oceanic as a back up. I have had my primary fail underwater. On time it told me I was at 13 feet while I was deploying my SMB at around 45 feet. It thought I was at 13 feet all the way through my ascent, safety stop, and for about 5 minutes on the boat. At that point it decided I was descending again, passed the 600 foot mark, then died. There have been several instances where it reverts to watch mode just as I enter the water, and as I descend it reactivates dive mode. By the time it has finished it's battery check etc, I am at 10 feet, and it starts there from 1. So then it is just 10 feet out for the remainder of the dive. I like having a backup.

I also work divemastering most days, so it's nice to have a backup that I can leave set to air when I am diving nitrox. That way I am tracking my dive as well as roughly tracking the divers who I am leading. That allows me to adjust the dive on the fly to keep the group on a conservative profile. Not the optimum way to lead the group, but it is the reality of working with fun divers at a resort.

 

[CaboJim]

About 2 years ago, I had a computer failure, during a dive. The battery door failed & water got into the computer. I finished the dive by using my buddy's profile(since he sucks air faster than I do).
I was out of the country when this happened. I was able to dry out the computer with & reseal the door. I wished, at the time, I had a back up computer. I now do....