Bollocks talked about computer algorithms. Aka how to bend an Oceanic VT3

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But you don't have the 5 income tax rate we have: 19, 20, 21 41 and 46%.
Just imagine what the tax rate would be without the kindly Mr Barnett's formula to suckle upon. 19/6 in the pound?
 
Ok, I have a guess.

I set the mix the night before the dive. Last night, for a previous reply, I set it again. This morning it is back to air. What is the behaviour on this? I guess there is a time limit and then it reverts to air. I would swear I was on the boat when I checked the NDLs though, oh well…

I have not figured out how to see the mix in the log entry for the dive that bent it...
Hi Ken, @KenGordon

Your guess very well may be correct. If you set the VT3 to nitrox, and then don't dive it, it will revert back to air in 2 hours, when the screen blanks. I don't believe this information is in the owner's manual.

If you dive the computer, it will remain set at that nitrox value for that entire series (all subsequent dives with a surface interval <24 hours), unless you reset it to a different value. If the surface interval exceeds 24 hours, the computer will revert back to air and start a new series of dives. You can always view the current setting by going to the planning mode. This is a quick and easy way to make sure you are set to the correct mix.

upload_2021-5-3_8-56-47.png


You can check to see if your computer was set for air or nitrox by looking at the dive log. The log preview will show nitrox at the bottom of the screen if you were on nitrox, it will be blank if you were on air. Likewise with the 1st log screen. If you were on nitrox, the 2nd log screen will give you your mix, on air, there is no 2nd log page.

upload_2021-5-3_9-4-35.png


upload_2021-5-3_9-5-15.png


If you download your dives (requires a proprietary cable for the VT3) you will likely also be able to see your mix, among other things. I happen to download to the Oceanic application, OceanLog. The dive, below, was a simple light back gas deco dive on 33% to 90 feet, 2nd dive of the day.

upload_2021-5-3_9-14-41.png


upload_2021-5-3_9-15-24.png


Let us know what you find out about the dive in question.

Take care,

Craig
 
Hi Ken, @KenGordon

Your guess very well may be correct. If you set the VT3 to nitrox, and then don't dive it, it will revert back to air in 2 hours, when the screen blanks. I don't believe this information is in the owner's manual.

If you dive the computer, it will remain set at that nitrox value for that entire series (all subsequent dives with a surface interval <24 hours), unless you reset it to a different value. If the surface interval exceeds 24 hours, the computer will revert back to air and start a new series of dives. You can always view the current setting by going to the planning mode. This is a quick and easy way to make sure you are set to the correct mix.

View attachment 656879

You can check to see if your computer was set for air or nitrox by looking at the dive log. The log preview will show nitrox at the bottom of the screen if you were on nitrox, it will be blank if you were on air. Likewise with the 1st log screen. If you were on nitrox, the 2nd log screen will give you your mix, on air, there is no 2nd log page.

View attachment 656880

View attachment 656881

If you download your dives (requires a proprietary cable for the VT3) you will likely also be able to see your mix, among other things. I happen to download to the Oceanic application, OceanLog. The dive, below, was a simple light back gas deco dive on 33% to 90 feet, 2nd dive of the day.

View attachment 656882

View attachment 656883

Let us know what you find out about the dive in question.

Take care,

Craig
A noble effort to get the thread back on topic.
 
the VT3 is also dual algorithm iirc, so DSAT vs Z+ may have come in to play
 
Hi Ken, @KenGordon

Your guess very well may be correct. If you set the VT3 to nitrox, and then don't dive it, it will revert back to air in 2 hours, when the screen blanks. I don't believe this information is in the owner's manual.

If you dive the computer, it will remain set at that nitrox value for that entire series (all subsequent dives with a surface interval <24 hours), unless you reset it to a different value. If the surface interval exceeds 24 hours, the computer will revert back to air and start a new series of dives. You can always view the current setting by going to the planning mode. This is a quick and easy way to make sure you are set to the correct mix.

View attachment 656879

You can check to see if your computer was set for air or nitrox by looking at the dive log. The log preview will show nitrox at the bottom of the screen if you were on nitrox, it will be blank if you were on air. Likewise with the 1st log screen. If you were on nitrox, the 2nd log screen will give you your mix, on air, there is no 2nd log page.

View attachment 656880

View attachment 656881

If you download your dives (requires a proprietary cable for the VT3) you will likely also be able to see your mix, among other things. I happen to download to the Oceanic application, OceanLog. The dive, below, was a simple light back gas deco dive on 33% to 90 feet, 2nd dive of the day.

View attachment 656882

View attachment 656883

Let us know what you find out about the dive in question.

Take care,

Craig

The log does not have the Nitrox icon at the bottom. However the manual does say it will not show the O2 details if you bent it so I cannot be sure whether it is because it was on air or not. Given what you say then this must have been user error on my part. I ought to have checked it in the morning. Lesson learned. All my other computers stay on the mix you set.

I will break it in more controlled conditions next time :)

I would rather it was sensible as a student lost my Helo2 so I don’t have multi gas backup computer anymore for accelerated deco dives. I bought an Apple Watch instead of a Garmin…
 
Hi @tursiops just replying to my friend, Ken. All the fish and chips and quid stuff came up before I got onto SB today :)
The last time I ate fish and chips was on from a van on the quayside in Stromness with a deco guru.

Some people have a very narrow view of what “on topic” means.
 
The log does not have the Nitrox icon at the bottom. However the manual does say it will not show the O2 details if you bent it so I cannot be sure whether it is because it was on air or not. Given what you say then this must have been user error on my part. I ought to have checked it in the morning. Lesson learned. All my other computers stay on the mix you set.

I will break it in more controlled conditions next time :)

I would rather it was sensible as a student lost my Helo2 so I don’t have multi gas backup computer anymore for accelerated deco dives. I bought an Apple Watch instead of a Garmin…
I have never gone into violation gauge mode on my VT3 in nearly 11 years, 1564 dives, 1645 hours, I wouldn't know :)
 
https://www.shearwater.com/products/perdix-ai/

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