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The regulator doesn't seem to regulate, it is about 30psi out.
Turning the knob on the front makes it open or close/stop the flow of Hydrogen.
Maybe it never adjusted, it just seemed right pressure and i accepted it. It does make it a little be odd to fill balloons to a precise lift. I have to use the valve on the tank itself to control anything.
The Smith regulator only does a fixed pressure step down. No control on the regulator except open(~30psi) or closed (0psi).
For near space ballooning it gets the job done, and for only $45. But a regulator that doesn't adjust regulation pressure does kind of freak some people out.