Backup computer

[DCDivenut]

Okay... I am probably going to get a new computer and I am wondering what to do with my old one. Old unit is a Genesis React currently in a console configuration. I will be replacing it with either a Wisdom or a Cobra.

I want to keep my old computer with me when I dive as a backup (I figure it will do me more good with me, than not). What are my mounting options? I don't want to wrist mount it or really put it in a "critical" position. since it is a true backup. Can I keep it in a BC pocket? Will it work properly? I could put it on a really short lanyard and attach it to one of my D-rings, but again, out of sight is preferable.

Any suggestions?

 

[diver69]

I'm also thinking about getting a new console. I currently use a Suunto Ayper wristmount. I really like Suunto, and like you am considering either a Cobra or Sherwood Wisdom. I like Wisdom for it's quick-disconnect feature. The closest I could find for Suunto is the Quick Disconnect they have, but it sounds like it's positioned between the 1st stage and the hose. Where as Sherwood has the Quick-Disconnect right at the end of the hose near the computer. Which means, with Suunto, you're gonna end up carrying you computer with you along with the hose, and the Wisdon, you can disconnect the computer and carry it around with the Quick-Disconnect, which is about 3-4 inches.

I've seen the Wisdom myself, but I haven't seen a Suunto. Any comments?

 

[J1M1]

put it in the drysuit pocket thats what i do and it works fine. Attach it to the backup tables in some fashion. That way you have both there when you need them. However this is really not the proper way to do it. If you pull it out of the pcket and drop it you are out a timing and depth device when it could be needed in a critical deco situation. If you put it in the pocket try to attach it to some sort of lanyard that way you know that it wont be dropped when needed or dropped and a loss of bucks... J.D.

 

[MechDiver]

put it in the drysuit pocket thats what i do and it works fine. Attach it to the backup tables in some fashion. That way you have both there when you need them. However this is really not the proper way to do it. If you pull it out of the pcket and drop it you are out a timing and depth device when it could be needed in a critical deco situation. If you put it in the pocket try to attach it to some sort of lanyard that way you know that it wont be dropped when needed or dropped and a loss of bucks... J.D.

If you put one or two 1/8" holes and grommets in your drysuit pocket(s), you can put in a loop of 1/8" bungee that is used to clip items to. That way you don't lose them.

MD

 

[Charlie99]

I am wondering what to do with my old one. ...I want to keep my old computer with me when I dive as a backup ...Any suggestions?

If you are doing non-deco recreational diving, then I suggest that you just leave your backup computer on the boat. Dive computer failures are rare if you remember to change the batteries. IMO you don't gain enough to make it worthwhile bringing along excess gear. The only exception would be if you are diving in such low vis that you need the computer to make a controlled ascent.

You have both your mental estimate of your profile and also your buddy's dive computer as backup.

The few times my backup computer has gotten wet, it has been to replace a buddy's computer that had dead batteries.


Charlie Allen

 

[Hallmac]

The closest I could find for Suunto is the Quick Disconnect they have, but it sounds like it's positioned between the 1st stage and the hose. Where as Sherwood has the Quick-Disconnect right at the end of the hose near the computer. Which means, with Suunto, you're gonna end up carrying you computer with you along with the hose, and the Wisdon, you can disconnect the computer and carry it around with the Quick-Disconnect, which is about 3-4 inches.

Your information is incorrect the suunto quick disconnect can be placed in eithor location and is most commonly placed on the console end of the unit.

Now back to your regularly schedule program

Hallmac

 

[ScubaRon]

If you are doing non-deco recreational diving, then I suggest that you just leave your backup computer on the boat.Charlie Allen

The boat is the last place you want to leave your backup dive computer:
if your main computer breaks down, a backup computer on the boat is not going to help you since it doesn't contain the profile(s) of your previous dives.
So take it down with you (in a pocket is fine) or leave it at home, but don't leave it on the boat.
ScubaRon

 

[MechDiver]

The boat is the last place you want to leave your backup dive computer:
if your main computer breaks down, a backup computer on the boat is not going to help you since it doesn't contain the profile(s) of your previous dives.
So take it down with you (in a pocket is fine) or leave it at home, but don't leave it on the boat.
ScubaRon

If you're on a multiday, multidive liveaboard maybe. Otherwise I agree with Charlie99, waste of time. There is always Rule of 120 to use in single or other "home" type dives. Backup computer for recreational diving is overkill.

MD

 

[Charlie99]

The boat is the last place you want to leave your backup dive computer:
if your main computer breaks down, a backup computer on the boat is not going to help you since it doesn't contain the profile(s) of your previous dives.
So take it down with you (in a pocket is fine) or leave it at home, but don't leave it on the boat.
ScubaRon

If you study the problem a bit, you will find it easy to do a contingency plan using the worst case on the tables. Use your contingency plan for the next dive, while carrying the new computer. While you can go through all sorts of complicated scenarios with tables (including USN deco tables), in typical rec NDL diving it pretty much always just ends up as nothing more than doing a full 60 or 90 minute SI, then doing the next dive conservatively and hanging a bit extra. The backup computer will be giving you the important data of depth and elapsed time. You just need to stay within the profile you planned on the boat, rather than diving the computer NDL.

If you are really nervous, or if you don't have a clue as to the actual profile of your last dive, then skip one dive on the live-aboard, or skip the 2nd dive on a dayboat. You are back in sync by the next morning at the latest.

Were dive computer failures common, or if the failure of the computer during the dive were life threatening, then I'd have a different approach.

Charlie

 

[domino22]

The boat is the last place you want to leave your backup dive computer:
if your main computer breaks down, a backup computer on the boat is not going to help you since it doesn't contain the profile(s) of your previous dives.
So take it down with you (in a pocket is fine) or leave it at home, but don't leave it on the boat.
ScubaRon

I agree take it with you. You never know when something will decide to give up the ghost.