Dive Timer with Multiple Alarms

[John Touhig]

Does anyone know of a dive timer into which you can program multiple alarms to remind you when to make a gas switch. I know this might seem a dull question but, I'm hoping to start a DSAT Tec Rec course in a couple of weeks and I'm wondering how people remind themselves as too when to make the gas switches in line with the dive plan?

Do you keeping looking at your plan and your timer/computer?

Do you all use computers that do this for you?

[Fathoms Down]

Originally Posted by GasMuncher2

Do you keeping looking at your plan and your timer/computer?

Very much so. For something as important as a gas switch then keeping your eye on the time is an important skill.

Originally Posted by GasMuncher2

Do you all use computers that do this for you?

I use a VR3 which reminds me (but doesn't have an alarm) when to switch but I also carry a set of tables and a timer and memorize when my switches are due.

[db8us]

Hi GasMuncher2,

a set of standard-gases helps a lot.
So if you use EAN50 and O2 as decogases it becomes a natural habitat to be "alert" when reaching this depths...
No Computer should replace brain-activity... Just think that in the future you might also have to be careful when decending, since bottom-mixes might be hypoxic.
Standards and Training are the keys, not more "tamagotchis"

This is of course my personal opinion :-)

Michael

[And]

Hi

The gas switch is driven by depth more than time

Andy

Originally Posted by db8us

'tamagotchis'

LOL

[Juz]

I always carry back-up tables, custom cut for each dive, but in essence for this type of diving personal discipline is key.

You should just KNOW when the switches are, and if you use standard gasses (I always use 70% to deco on) then the switch becomes habit - for me, it's always at 12m.

The computer is purely a tool, never rely it.

Juz

[Pierre Farrugia]

Hello,

As michael said, using standard deco mixes help, but when you get used to a slate with runtimes, everything is much easier, no need to force your bain either, just follow the schedule. Eg if I use 60% I know that I will change at 15m.

Regards

Pierre

[Mark Powell]

On my run time slate I usually mark the stop at which the gas switch is to take place. A box around the depth/time is an easy indicator.

I also make sure that I know when my first deco stop will be and my first gas switch.

[NotDeadYet]

I'm with Michael. No disrespect but if you need a mechanical reminder to switch gases then you shouldn't be doing dives which require gas switches. I use a Uwatec bottom timer for everything, doesn't give me any info I don't need like ceiling, deco time, etc., it doesn't beep at me or have any fancy pictures to distract me. I want something to take a quick look at now and again without having to think about what it's showing me.

Cheers,

Stuart

[alunharford]

To disagree with pretty much everybody on this, the reason I dive with a computer (at all) is to help prevent my own stupidity killing me.
I'm not normally stupid, but like everybody else (I expect) I do really stupid things at times.
Mis-using my tables or writing down the wrong numbers and not noticing would take pretty serious stupidity, but I've done more stupid things in my time (thankfully none of them in a situation where my life was at stake).
I carry my dive computer so it can tell me not to do something totally stupid.

Forgetting to do a gas switch requires stupidity, but I'm sure everybody could be stupid enough to do it (although not many - nearly zero - will). If something reminds me then its got to be a good thing, as long as it doesn't get in the way of other stuff.

[Pierre Farrugia]

I am pro VR3 use and not against, but one must have experience on runtimes and gas switches. If your computer fails you will have to go to tabels and be able to get out safe. I would suggest to Gasmucher to first do the course where he will get more at ease with runtimes, then after a couple of times you can get used to this system and even know it's advantages. Eg you cannot plan for a 20min bottom time and forget, tech diving is all looking at gauges and time and slate. If you are not sure start doing eg. 30m 20min dive with runtimes for a 45m 30min dive so if you do any mistake you will skip simulated deco.

Practise makes perfect, if in douth do a lot of simulated deco!