Vintage Double Hose

I got this from my friend as he was closing down shop a while back. He had told me it was a trainer for J-Valve use. Hoping someone can tell me more about it. Operation etc.....

We had one of those a long time ago, but by that time the J-valve was sort of past its prime anyway, and we never got around to using it in our classes. I can't find it in my old stash, so I must have given it away. I never would have thrown a valve away.

My memory of its operation is a little foggy (maybe from collecting those little purple regulator bags), but it seems like once you installed it in your tank and filled it with the lever down it was ready for operation. With the lever up, air was captured in the inner container below the valve, and that small volume was isolated from the rest of the air supply. That was just enough to breath for a short while until it got harder to breathe, and then, just like the normal J-Valve operation you lowered the lever to access the balance of the air supply. Then the lever could be raised again, and the whole thing passed to another student to repeat the J-valve learning process without each person having to breathe a whole cylinder down.

It would have been an effective training device if it had come out in the 50's or 60's, but I think it was a little late, becoming available after gauges were already in common use.

That is a neat find. I just recently bought a cut away of a scubapro j valve. I will be getting pics of it on The Scuba Museum site soon I hope.

Cool! Thanks for the explanation. I figured roughly that's how it was supposed to work. My friend said he was still using it in the not too distant past for training police divers. I have practiced running low plenty with regular tanks myself.... but maybe I will put it on a tank sometime for grins.