Wrist Computers - I Need Your Advice

[TSandM]

the trusty SK7 analog compass in a spot that is more logical for navigation than the wrist.

Can you explain this? I carry my SK7 on my wrist, and find it quite easy to use; far easier than it was on a console where I had to pull it up to look at it.

 

[fnfalman]

Computer this, computer that.

Bah!!! All you need are: good compass (SK-7), good SPG, good depth gauge and a watch. Heck, if you use a Doxa, you don't even need dive table since the US Navy NDL dive table is built right onto the bezel. Sure, a computer can handle most of these duties, but my rig doesn't require batteries or electronics. Not to mention it makes me feel like I was diving with Mike Nelson or something...

 

[redacted]

My $68 Oceanic data plus in a $12 DSS wrist mount seems to give me all the information I need to dive safely. Just what additional capability do you get for the other $1,820?

 

[Superlyte27]

Before you buy anything, check with me and see if I can beat your best price

 

[aquaregia]

SK7 analog compass in a spot that is more logical for navigation than the wrist.

I really like the compass on my forearm (near elbow) because it allows me to navigate while I shiver.

 

[Mike Boswell]

Mike, I monitor my dive time and my profile in my head as I dive. I don't use a computer to determine my no deco limits or the shape of my dive. So having my dive time easily available is key. Time is also gas; I can usually tell you, based on starting gas, profile and time, how much is in my tank, and I'm often accurate to within 100 psi. It's an awfully nice facility, and ones gauges become backups.

As stated, I use my computer on my right wrist, so that it can be watched while ascending and leave the left hand free to use the inflator or dump valve.

I would HIGHLY recommend trying to borrow and try a gauge with a digital compass in it, before you pay any additional money for that capacity. I've been totally underwhelmed by both of the ones I've tried.

Lynne - You have mentioned this before, and I have NO IDEA what this method is called, or how it works. Care to give me a hint?

 

[Hatul]

Can you explain this? I carry my SK7 on my wrist, and find it quite easy to use; far easier than it was on a console where I had to pull it up to look at it.

OK, which is better, to have the compass on the wrist or at the end of a small console on a small retractor. I easily pull out my console and the lubber line of the compass is naturally pointing forward in the direction I'm traveling, every time.

You have to bend your elbow and first line up the lubber line with the forward direction, if you're off your navigation is off. If you get distracted and your elbow flexes or extends your navigation is off. Sure you don't need accurate bearings but why add another error to the process.

You're swimming with your left forearm in an awkward fixed position and I'm just holding the console in front of me, which I think is more natural.

When you're suiting up the wrist compass gets caught on the shoulder webbing, I don't have this problem. And it's another to don when suiting up, and another item that can get lost.

The Cobra is a very compact console and perfect for attaching the compass at the end. Just put the Cobra on a nice long Miflex HP hose and attach with a small retractor and it makes a great compass holder.

Adam

 

[vjanelle]

Lynne - You have mentioned this before, and I have NO IDEA what this method is called, or how it works. Care to give me a hint?

Math + experience.

Air consumption increases every 33'/10m by another ATA (2 ATA at 33', 3 ATA at 66', etc). Knowing your SAC rate + ~depth * time, you should be able to estimate very easily within a reasonable amount (200~ PSI) what your SPG'll say.

You reinforce checking the SPG with newer divers because their air consumption will drop dramatically with experience. You should get an idea of your SAC/RMV for various types of diving (mine goes up when watching people, etc).

 

[Hatul]

Mike, I monitor my dive time and my profile in my head as I dive. I don't use a computer to determine my no deco limits or the shape of my dive. So having my dive time easily available is key. Time is also gas; I can usually tell you, based on starting gas, profile and time, how much is in my tank, and I'm often accurate to within 100 psi. It's an awfully nice facility, and ones gauges become backups.

As stated, I use my computer on my right wrist, so that it can be watched while ascending and leave the left hand free to use the inflator or dump valve.

I would HIGHLY recommend trying to borrow and try a gauge with a digital compass in it, before you pay any additional money for that capacity. I've been totally underwhelmed by both of the ones I've tried.

Hello Lynne, I hate to be critical, but in another thread you point out how this advice could have led to your demise. The idea that you can use your head to take the place of frequent gauge checks does not sit right. It assumes that everything is going OK. For example there may be a leak you're not aware of. Thinking you have this much air or this much time is never a substitute for looking at the gauge and looking at the computer no matter how smart you are.

Which is why I like the console concept-- one glance give me my bearing, my computer and the SPG gauge.

Adam

 

[idocsteve]

I wouldnt bother with AI - you still need to carry an analogue backup

FALSE

I've used a VT Pro Air Integrated wrist computer and it's never failed me other than momentary loss of signal which never lasts more than a few seconds. I have a BCD mounted octopus and I'm down to a very streamlined 2 hose rig.

I bet you can pick up a pair of the VT Pro earlier models which is what I use for less than $800 for the pair.

On a few dive vacations I have brought along a set of gauges on a hose (not connected to my regulators), and I carry in a pocket, a BCD retractor mounted VT computer (not air integrated, to track residual nitrogen) "just in case" of a catastrophic failure of the wrist computer but I haven't needed to use them.