Sunnto VyTEC/D9 alogrithms

[whitehead]

Does anyone know if the D9 has switchable alogrithms?

On my Vytec there are two alogs' "100" and "50". I found "100" to be too restrictive (too "safe") for my personnal use so use the "50" exclusively. Does anyone know if the there is an equivalent of the "50" on the D9?

I would really like to buy a D9 but the thought of diving on an alog' which is as "safe" as the "100" would put me, personally, off.

Cheers

 

[teknitroxdiver]

alog=algorithm?? Assuming that...

I think those are conservancy values, which add a padding in addition to however much conservancy the algorithm in question has. Each computer uses only one algorithm, such as Suunto Deep Stop RGBM in the case of the D9. I don't see anything about a conservancy setting on the Suunto page, but every Suunto computer I've seen has one in some form.

The Vytec uses an "adjustable Suunto RGBM model". So all of these are the same algorithm, just with the ability to add some cushion to the profile.

 

[Vie]

Does anyone know if the D9 has switchable alogrithms?

Only the HS Explorer has that, as far as I know. You can set the Explorer to modified Bühlmann (ZH-16 with RGBM folding) or RGBM.

 

[Hoosier]

Sure. D9 has the same option either 100 or 50. I think that D9 is just upgrade model of Vytec in Suunto.

Does anyone know if the D9 has switchable alogrithms?

On my Vytec there are two alogs' "100" and "50". I found "100" to be too restrictive (too "safe") for my personnal use so use the "50" exclusively. Does anyone know if the there is an equivalent of the "50" on the D9?

I would really like to buy a D9 but the thought of diving on an alog' which is as "safe" as the "100" would put me, personally, off.

Cheers

 

[vjongene]

Sure. D9 has the same option either 100 or 50. I think that D9 is just upgrade model of Vytec in Suunto.

To be more precise: the RGBM algorithm can be set at 100% or 50%. Unfortunately, the manual is not very explicit as to what this means.

 

[Hoosier]

Thanks for pointing it out. The unit is important. BTW, so, which setup do you use either 100% or 50%? I was told that Suunto's 100% is very conservative set up. Any thoughts?

To be more precise: the RGBM algorithm can be set at 100% or 50%. Unfortunately, the manual is not very explicit as to what this means.

 

[vjongene]

Thanks for pointing it out. The unit is important. BTW, so, which setup do you use either 100% or 50%? I was told that Suunto's 100% is very conservative set up. Any thoughts?

No thoughts yet. I have done only one dive with the D9 so far - very cold weather and snow over the last few weeks. It is currently set at 50% RGBM and deep stops. I have to experiment with parameters during a dive vacation where I do multiple dives a day.

 

[abowie]

There's not a lot of fact available on the "Suunto RGBM" algorithm, presumably because it's proprietary. Best I can find is here.

As best as I can surmise it seems to work by adding a "fudge factor" to its nitrogen algorithm which might even be a Haldanian model (I'm not sure about this at all though) in situations where microbubble formation is considered to be more likely. The "50" setting just halves the effect of the fudge factor.

It says these situations include "continuous multiday diving, closely spaced repetitive dives, dives deeper than the previous dive or rapid ascents which produce high microbubble build-up".

What it then does is one or more of shortening your NDL, adding a mandatory safety stop, lengthens any decompression stops or advises a prolonged surface interval.

Suunto computers do also offer a "personal adjustment" option to make times and stops more conservative. They also offer an altitude setting and the effect of P1 (the first personal adjustment level) is exactly the same as A1 (altitude 2500ft).

Personally my view of a computer is that it is designed to get you out of the water safely. I'm sort of surprised to hear you say that the computer is "too safe" for you when you don't actually understand what the changes you're making involve.

Although I don't pretend to be an expert on the Suunto model (not enough information available) it seems that what it does is to offer some added protection in situations where some rules of good diving practise are breached. Presumably if you don't do any of the things Suunto list then the RGBM "adjustment" doesn't happen.

 

[Hoosier]

Thanks for your info. If then, we can expect 10 adjustment combinations under the assumptions: A1=P1, A2=P2, 100% and 50%, respectively.

I acknowledge that it is a great feature for the safe diving though. Sometimes, it is a relatively too much conservative to any other computers. So, I have been wondering how to understand the difference between 100% and 50%. The manual just explained that 50% is only for the expert and highly trained diver. I look forward to seeing what result "Vjongene" has after the experiments. It is a good start to figure out one by one.

Thanks all.

 

[stoiclown]

I use the Vytec Computer, & shortly I will be upgrading to the D9. Just incase this point wasn't covered, Even though you turn the computer down by 50%. The accent rate is set @ 30 fpm no matter what setting you use.