Should I have a backup computer?

[CT-Rich]

The need for a back-up depends on the budget and the type of diving. If you are diving over a hard bottom with a max depth of of say 40fsw, you don’t need any computer, much less a spare. Computers are nice even on shallow dives because they can do a lot of things that used to be done by multiple gauges.

If you are a technical or cave diver, redundancy is part of the religion. The down side to that is you are running the backup in gauge mode or setting the gas mixes on two computers. On dive travel a spare puck computer in your BCD may save the day on trip. But again, only if you took the time to make sure you are switch gasses (four dives on nitrox may look like you are in deco on a computer that thinks you are diving air). For most divers starting out, you will run out of air before hitting deco in most situations. In the unlikely event your computer dies, use your good judgement to finish the dive safely and decide if you can do subsequent dives without it.

Personally, I change the battery at the start of the season. I haven’t paid anyone to do it for me and I have not flooded mine yet. YouTube has videos to show how to do it for almost all brands.

 

[BoltSnap]

Unless you are going on a once in a lifetime trip, not necessary IMO. Your buddy has your backup.

This is wrong and potentialy unsafe!

 

[BoltSnap]

And reckless irresponsible advice that a new diver will hopefully disregard.

Yes, yes and yes!!

 

[Steve_C]

I cannot count how many dives I have poked around in the sand and looked in nooks and crannies while my buddy has floated 10-15 ft above me looking at the fishies swimming by. Our computers can be radically different in terms of NDL. We also have played reverse roles at times.

 

[CT-Rich]

A dive computer is not a life sustaining device. Yes, making a habit or repetitive dives using a shared computer is unwise, but we are talking about the failure of a PCD, which is the exception not the rule.

A dive buddy carries an octopus as a redundant air source, but you wouldn’t rely on him to share air for the entire dive. If you are making a recreational dive WELL within the NDL (like 40 minutes at 40’) not having your own computer shoul not be a deal breaker. Your dive buddy can give you the data for your log book.

You will need to be much more conservative (i.e. diving tables) and need a long surface interval to clear N2 before using a new computer. But that is a pretty rare situation and the cost and additional work involved in having a back up PDC and salvaging the day of recreational diving is not worth the trouble.

 

[broncobowsher]

It has been hinted at above, but what dive profiles do you dive?
If it is recreational 60' touristy stuff, a single computer is fine. Even if it fails it is no big deal. If you have a halfway decent training you shouldn't need a computer at all. A single computer is your backup computer.
Now if you are doing a liveaboard and plan to do 4-5 dives a day for a week with no other resources, or plan to get deeper, or will be pushing into the technical side of diving. This is when you start shopping for a second computer. Or what happens a lot is the original computer you got is now the backup and your new computer is the primary. 10 years ago I got a slightly better than average Oceanic with nitrox. Later I upped my game and started wanting more. Got a Shearwater as the new primary. But those recreational dives, still has the Oceanic hanging off the console. That is the backup. Once I start playing around the 100' mark, I will always have both.
If you plan to do the air integrated, now things get more complicated. Loosing a computer now means you lost your pressure gauge. That adds a whole new layer to the mess. Unless you still keep one on a hose.

 

[Bob DBF]

Unless you are going on a once in a lifetime trip, not necessary IMO. Your buddy has your backup.

This is wrong and potentialy unsafe!

And reckless irresponsible advice that a new diver will hopefully disregard.

Yes, yes and yes!!

I certainly would like a depth gauge and a reading of the ascent rate as I was surfacing after my computer puked, not that I need it, but it would be easier and safer to use my buddy's computer than winging it.

It would seem that switching to tables and continuing the dive, as was suggested earlier in the thread, would have elicited a greater response sooner.



Bob

 

[Joneill]

A dive computer is not a life sustaining device. Yes, making a habit or repetitive dives using a shared computer is unwise, but we are talking about the failure of a PCD, which is the exception not the rule.

A dive buddy carries an octopus as a redundant air source, but you wouldn’t rely on him to share air for the entire dive. If you are making a recreational dive WELL within the NDL (like 40 minutes at 40’) not having your own computer shoul not be a deal breaker. Your dive buddy can give you the data for your log book.

You will need to be much more conservative (i.e. diving tables) and need a long surface interval to clear N2 before using a new computer. But that is a pretty rare situation and the cost and additional work involved in having a back up PDC and salvaging the day of recreational diving is not worth the trouble.

Sorry, but I'm a recreational diver that stays within NDL and with ALL Ops that I've dived with, you are not allowed to dive without a computer AND, if your computer were to fail during a dive, you are not allowed to dive again that day. You then have to either rent or buy a new computer for the next day or you're done for the trip.

So, I don't see how you can say that owning a backup computer that prevents the possibility of those issues "is not worth the trouble"? It's a risk/benefit decision for all divers to make - but a no brainer for me!

 

[CT-Rich]

This is a basic forum and the OP with fewer than 24 dive asked if he should buy a back up computer. The answer is he probably should save his money for the moment. Are there situations where a computer back up is essential? Yes.

But as a new diver with tons of task loading, a second computer is not one of them. Computer fails? Make a safe ascent. Can he make a second dive? That depends. Where was he in relation to the NDL? If he was doing a couple of shallow shore dives, why not and just plan a as if the first dive was done as a square profile. Plan conservatively. Until the 1990s that was how virtually all diving was done. If you don’t know what your dive profile was previously, sit it out and wait 12 hours and get your computer battery changed. This will likely happen once a year unless you proactively replace the batteries.

On a live aboard, yeah, a back up is good. You upgrade to a new computer? Sure. But a new diver plunking down a couple of hundred bucks for a back up when they are newly certified? Hell No. He may decide that he want a more elaborate computer to better match his needs and end up with a three computers, a primary, a back up and clutter.

If you can’t figure out tables, go snorkeling or take a nap, no harm no shame.

 

[Bob DBF]

It's like saying you don't need to fins because you can always just kick harder with the one.

To me it seems more like losing a fin and not having your buddy assist you to safety with his fins because, for some unknown reason, it is unsafe.

I have used my buddy's depth gauge and watch to make a safe ascent, I see no reason not to use his computer to do the same. @seeker242 would have to say whether he meant to use his buddy's computer to make a safe exit from the dive or continue to use it for that dive, and the rest of the dives for the day. Could be I'm misreading his intent.


Bob