8 replies to this topic

[shadragon]

I have an opportunity to upgrade my current EMC-16 to either a EMC-20H or a Gemini. The 20 is the next step up in computers, but I have never seen a Gemini. Is there anyone on the board who can comment on how it works?

I am interested specifically in ease of setup and mounting as I will have to swap this back and forth between my recreational BC and doubles harness. However, all comments welcome.

Thanks.

[Scubatooth]

Sha

The gemini is a air integrated computer where a majority of the brains of the computer are in the black box that attaches to the first stages high pressure port. you can upgrade to the intelligent wrist unit that will have all the function of the black box minus the pressure reading should the connection be lost. All in all I would think the 20 would be a better option then the 16 if your going into tech with helium gases, if not stay with the 16.

[shadragon]

Cheers. So how does it mount to the BC or harness? Is it easily transferable between rigs?

Any down side?

[shadragon]

Thanks PPM. Am not worried about moving from Reg to reg as I use the same MK 25 on my rec rig and doubles. It is the unit mounting to the BC / harness that I was wondering about and ease of transfer.
I hear what you are saying, but I doubt helium will ever be a part of my life. Good old NITROX is fine with me for diving.

[shadragon]

Cheers. It does sound a bit of a faff to get it back and forth so I will skip that.

Am still quite happy with my Cochran so will stick with that brand.

Thanks all.

[georoc01]

Mounting the brick (and the dive computer portion of the device IS the size of a small brick attached to the first stage)is accomplished in one of two popular methods:

--attaching the two pressure clips on the back of the brick to the inflator hose;

--attaching the two pressure clips on the back of the brick to the Octo hose.

BOTH of these options require that you force the clips onto the hose, so you may want to watch out for friction at the pressure points where the clips connect.

Note that the obvious third option--letting the brick hang free from the installed transducer cable attached to the first stage--will quickly result in damage to that cable and a dead dive computer. Many folks damage their Gemini by picking up their gear by the cable as well.

If Nitrox is all you wish to dive, and you are sold on the idea of a hoseless computer, you may want to look at the one I dive:

Aeris Elite T3

You'll note that the transmitter on the first stage is only for the PSI/Bar portion of the computer, with the actual dive computer in the puck. Cochran, for reasons of their own, built the Gemini reverse to this. It's also a lot smaller and less cumbersome as a result.

PPM

I did my Tech diving with both a Cochran EMC-20H and the Oceanic equiv of the T3 (Atom 2.0), which supports O2 mixes up to 99%. The differences in deco times were very minimal. The only difference is that with the Oceanic you had to tell it when you changed gasses where the Cochran assumes you changed gasses when you cross a depth threshold you set up prior to the dive.

[Scubatooth]

Simon

Sorry for the delay, my schedule is a bit off kilter and random right now.

It is transferable but not ideal as the HP sensor is screwed into a HP port of a first stage. When i dove doubles i would typically zip tie the black box to the manifold crossbar. Now my Gemini is limited to when i will dive a single tank as for sidemount its not to useful as it can only tell me data of one of the tanks. Now if the upgrade to intelligent wrist unit isnt too much i may do that so i have a secondary computer.