Bruce and others: Been reading with inerest, and not commenting, as Mike has taken the charge and is doing a bang-up job of it.
Now that the discussion has gone to the predicatble level of where we'll all talk about reliability of electronics for another 1000 posts without any real result...
, let me offer my ideas.
Starting this summer, I'll be diving a hybrid rEvo: The system can be configured in 2 very different ways in about 5 minutes, no tools needed. And while configured in the "Mode A" way, it can be used in two TOTALLY different ways. Let me first articulate how it can be configured, and then how I plan to exploit it to my advantage (I hope).
Configuration "Mode A": Blocked First Stage feeding both solenoid and orifice.
Configuration "Mode B": Unblocked First Stage feeding solenoid only, Orifice Blocked off (no flow).
Simple, eh" Remove the first stage cap and then install an orifice plug to go from "A" to "B" and reverse the work to go back.
OK.. how to use it?
Mode A is the "normal" one for anything shallower than about 240 feet. Guess what? This represents about 90% of what I do. So, how to use it there?
I think the thing is to CHOOSE ONE WAY and then just let the other system run in parallel and essentially ignore it.
If you believe than a mCCR is the way to go, run the setpoint at 0.5, forget that the controller exists (save for doing deco calcs) and fly the unit as a true mCCR. If the solenoid fails... so what. You NEVER expected it to fire anyhow and are not relying on it. It'll sit there, transparent, just latent and waiting.
If you believe that a eCCR is the way to go, set the setpoint up to 1.2 and let the solenoid do it's work. Monitor the system like any other eCCR and forget that the orifice even exists. It'll be there, transparent, just humming along.
And if you want to change "philosophies mid-dive? Go for it. You just need to be able to ACCURATELY switch your brain from one mode to the other WITH NO ERRORS. I think, really, that the ONLY way to be able to do this is to have substantial habit pattern experience with BOTH eCCR and mCCR systems PREVIOUSLY (likely on other units, or this particular unit configured as an either/or system).
Why am I doing this myself? Simple: I'm teaching the unit and need to be able to teach BOTH methods of use to my students. It does not make sense to modify the unit to an either/or rig every time the situation changes. Would I deliberately ADD this sort of system to a rig that was not fitted with it 'out f the box"? Probably not. I'm quite happy with *either* a mCCR or an eCCR and really don't see the "need" for both. Now, with that said: I think that the hybrid system that I have (2 rEvodreams, one orifice, one solenoid, and a Shearwater cntroller) absolutely ROCKS from an "expedition reliability standpoint". If/when any of the 'lekkies goes tits-up, I can still continue my trip with the rig by just changing my BRAIN over to the other mode. I can dive it as a mCCR using any ONE of the three 'lekkies boxes. That's pretty darned reliable.
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"Mode B" is how I'll configure the rig for deep diving. it becomes a pure eCCR for that work. Not a lot to discuss there: It's just a Shearwater controlled eCCR with dual rEvodreams/HUD's for monitoring. Still pretty darned capable from a monitoring reliability standpoint.
Anything else I'm missing? Bruce? Mike?
Dave
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