Have often wondered if the Revo solenoid and orifice could be separated such that they could be fed by two regulators; one variable IP, one fixed IP.
Then the solenoid and manual add could continue to work on the bottom phase when the orifice stops.
Appreciate this would require more internal plumbing for an additional line into the exhale counterlung which the factory would need to do, which would crash headlong into the CE type approval constraints.
Seems too complicated to me. For starters, it means two 1st stages for O2 which means two O2 tanks which means...
The other solutions, while not perfect, don't overly complicate things. Barring any unforeseen issues, the 13.5 bar IP 1st stage and revised orifice seem to offer the best alternative IMHO.
- brett