I am retired from all that now, I did my first service course in 1985 while I was still in the Navy and for years before that just dived what I was given, I knew how they worked but a new respect for the engineering required to build such a simple solid device to breath at depth started from then on.
You know what? These regulators were designed and built without computers, and what worked back then, is the same as what works now, piston or membrane [which is even older], how many people know that?
You want simple, look inside a Scubapro Mk2, a trained ape could service it [and I am sure some do] .
Sorry for the rant.
Anyway here is a little history of who is the real hero of many modern regulators, and it it is NOT some French dude.
This is the first regulator I was given to dive in 1968 and it was an old set even then.
Ted Eldred.
Porpoise is a tradename for scuba developed by Ted Eldred in Australia and made there from the late 1940s onwards. The first Porpoise was a closed circuit oxygen rebreather, and the following models were all single hose open circuit regulators.
www.vintagescubagear.com.au
BZ