GEM recreational rebreather

[divejay]

A GEM and training can be had for about $4000. A KISS Sport plus training will run around $6500. Add a Shearwater, which isn't really needed, and it's still about $1000 less. Then you have the additional task loading of running the Sport. The GEM runs itself. The only thing you need to do is control your breathing, which also has to be done on the Sport. The GEM really is a great unit. I hadn't even considered a PSCR until it was released.

I own a CCR Kiss Sport (2 years old) and now the new SCR Kiss GEM. If you are interested, I am selling my used Kiss Sport for $3,000. I paid $5,100. It is in great condition. I really enjoyed diving the CCR Kiss Sport for the past 2 years but the SCR GEM better suits my daily needs here in Grand Cayman. The GEM being a SCR, there is a small amount of bubbles on every exhale but I'm still getting the up close pictures of the marine life I need.

 

[DepthCharge]

and now you are also dealing with an inconsistent nitrogen loading (unless you now buy a computer like a shearwater or VR... for around $1500+).

I'm not sure I understand this statement How does a computer influence your N2 uptake

 

[fishb0y]

Sure... with a SCR your FO2/PO2 is constantly changing, so you can't just set your nitrox computer for a specific mix or even a set PO2. For some reason most manufactures only sell o2 monitoring as an option.

 

[Dive-aholic]

Sure... with a SCR your FO2/PO2 is constantly changing, so you can't just set your nitrox computer for a specific mix or even a set PO2. For some reason most manufactures only sell o2 monitoring as an option.

Not exactly true. While your PO2 is changing, as long as your breathing rate and effort remain fairly constant, the FO2 will remain constant. I set my dive computer at a fixed percentage lower than what's in my cylinder and compare the PO2 on the computer with the PO2 on the display and they have been very close. The only difference is my PO2 display reads out to 2 places while my computer only reads to 1 so my computer rounds more.

 

[DepthCharge]

Sure... with a SCR your FO2/PO2 is constantly changing, so you can't just set your nitrox computer for a specific mix or even a set PO2. For some reason most manufactures only sell o2 monitoring as an option.

Well, last w/e the difference in my PO2 from going with the current on a drift dive, to fighting the current (1-2 knot) was 0.03 @ 85 ft. That comes out to a difference of about 1% on the surface, not much. This was on a GEM. My FIO2 was approx 31 from a 36% tank. So set a nitrox computer @ 30% and you have some lee-way. If you were talking about and active add SCR you would be correct, but not with a RMV keyed passive add SCR.

 

[Lobzilla]

Hi Rob,

Mike Young, the designer of the GEM, mentioned that the GEM was born "300' deep in a cave". Is there any information publicly available of the early prototypes or can you tell some stories?

 

[Dive-aholic]

Give me a month. I'm spending a week in Cozumel with Mike cave diving. I'm sure I'll come back with some good information for you.

 

[Thalassamania]

If you don't mind paying $4K to $5K for a semi-closed circuit rebreather (think Drager Dolphin) knock yourself out ... I can't see it myself, gotta use Nitrox, no helium, constant stream of small bubbles, good to 100 feet at best.

True, it is remarkable simple, easy to use, and compared to ECCRs, has much less risk.

 

[Mr.X]

Hi Rob,

Mike Young, the designer of the GEM, mentioned that the GEM was born "300' deep in a cave". Is there any information publicly available of the early prototypes or can you tell some stories?

That's a very catchy line. If it's lineage is PVR-BASC I would peruse the development of some of the early Jack Kellon designs, or examine this site: Halcyon PVR-BASC The early Halcyon PVR BASC designs were called refrigerators. Seeing guys buckle this giant on vs. my smaller CCR was funny. That said - no one in the WKPP camp would even touch a CCR back then as they were considered by the group as evil, or something else.

 

[Dive-aholic]

If you don't mind paying $4K to $5K for a semi-closed circuit rebreather (think Drager Dolphin) knock yourself out ... I can't see it myself, gotta use Nitrox, no helium, constant stream of small bubbles, good to 100 feet at best.

True, it is remarkable simple, easy to use, and compared to ECCRs, has much less risk.

Certainly, you're not referring to the GEM here. The GEM has been much deeper that 100 feet and can use helium. It does work a little differently at depth, but it's still very simple to use. I've had mine to 150'+ on 3 dives so far and it performed flawlessly.