Backup computer questions

[Michael Guerrero]

Shearwater primary and puck computer in gauge mode as my bottom timer. Dive profile is pre-planned on a slate so that I can revert to my written plan and back up bottom timer.

I do this too, but if I had two shearwaters I'd run those.

 

[doctormike]

When I was doing OC tech, I would have two Petrels on my right arm, and a bottom timer and slate (with an ascent profile) on my left arm. Probably didn't need the second Petrel, but I had it so I figured I would take it - would rather default to a second computer than ascend using a plan that didn't match my actual dive.

Now I dive a JJ, so I have the controller (Petrel) on my left arm, a NERD and a stand alone Petrel on my right arm. Thinking about ditching the stand alone Petrel.

 

[tbone1004]

Better?


FWIW I use a Perdix for primary on OC and a Nitek Q as backup. I have the Q as a spare cell reader for CC but much prefer the Perdix. I run the Nitek on a slightly more aggressive GF as a get out fast method if needed.

thankfully shearwater lets you adjust the GF hi during the dive so you can crank it up if you have to

 

[Doby45]

I have a Petrel2 but am seriously looking at getting the Hollis TX1 as my backup. Runs same algorithm as the Petrel and for giggles in the future I could run WAI on the TX1 for gas tracking in dive software.

 

[Doppler]

So redundancy is the name of the game. Do you run two of the same computers? Do you run a computer and a bottom timer? Two different computers? I currently dive a Petrel 2 and I am starting an/dp so I need a backup solution, and I'm wondering what other people are doing. I have thought about picking up another petrel 2 so they would be / function identically, but the idea of both computers running the same firmware / software seems like it could be construed as a single point of failure.

If your course is being run under TDI guidelines, your buddy has your backup computer... you may wish to have a digital bottomtimer / depth gauge, and that is all you need. The ascent schedules will be calculated and written down before the dive so that there is no doubt about the profiles you and your buddy will be following during your class.

 

[stuartv]

I have a Petrel2 but am seriously looking at getting the Hollis TX1 as my backup. Runs same algorithm as the Petrel and for giggles in the future I could run WAI on the TX1 for gas tracking in dive software.

I have a SeaBear H3 for my primary and recently got a TX1 to be my backup. I just got my Helitrox cert, which means diving with Helium, so I wanted a backup that would support trimix.

I really do like getting my gas consumption data from the TX1. But, otherwise, the jury is still out on it. I don't want to go further OT here, so if you're interested in the TX1, keep an eye out for future posts with more of my experience.

 

[Doby45]

I have a SeaBear H3 for my primary and recently got a TX1 to be my backup. I just got my Helitrox cert, which means diving with Helium, so I wanted a backup that would support trimix.

I really do like getting my gas consumption data from the TX1. But, otherwise, the jury is still out on it. I don't want to go further OT here, so if you're interested in the TX1, keep an eye out for future posts with more of my experience.

Will do bud, thanks!

 

[RainPilot]

thankfully shearwater lets you adjust the GF hi during the dive so you can crank it up if you have to

Indeed it does, I luckily have a GF computer anyway to use as a backup and its one less thing to worry about if i have my hands full in an emergency.

 

[DevonDiver]

I carry a Petrel 2 and a bottom timer (Suunto Vyper in gauge mode).

Sometimes, for sh1ts and giggles, I'll carry an analogue depth gauge and run ascents using that and my analogue dive watch. There's something holistically pleasing about doing stops on a needle, not a digital screen.

In the unlikely event my Petrel failed, I'd surface using back-up/contingency tables.

Having the tables present gives me a real-time reference of the planned deco/runtime, which helps prevent human factors failures.

The other human factor issue is that having to create and write out all those tables guards against complacency and corner-cutting in the planning phase.... something that'd be an insidious temptation if using another technical computer as a back-up.

 

[Doppler]

When I was doing OC tech, I would have two Petrels on my right arm, and a bottom timer and slate (with an ascent profile) on my left arm. Probably didn't need the second Petrel, but I had it so I figured I would take it - would rather default to a second computer than ascend using a plan that didn't match my actual dive.

Now I dive a JJ, so I have the controller (Petrel) on my left arm, a NERD and a stand alone Petrel on my right arm. Thinking about ditching the stand alone Petrel.

Hi Michael. Be interested on your expierence with the Nerd. I love Shearwater products and the CanDive controller software, but never grew into the Nerd... found it too intrusive... kept bashing into cave walls and ceilings. LOL!