Vintage Double Hose

I picked up a U.S.D. 3/4" valve on EBay that is described as a "clanker" (which name was worth the price of the valve all by itself). It apparantly works by slapping a teflon button against the inside of the tank when one is "on reserve".

What I'd like is a better idea how they were used. It has, instead of an up-or-down reserve arm, a spring-loaded arm that functions very much like a toilet flush arm, being spring-loaded and returning to center when released, with an eye on the end of that lever that looks like a pull rod could be attached. Do these valves function like the usual J valve, where they stop passing air until you pull the arm down, and then clank until you run out of air, or do they work in some other manner?

Thanks- Al.

Down load the 1964 catalog, there is some info on it there. From what I can gather, the vavle "signals" once you are low on air....and it appears it keeps on doing so until you surface.....just what I need a nagging wife valve.
The lever is a test lever, you pull it to verify the banger is working and you can use it as a tank knocker to get your buddies attention. A friend of mine who collect such stuff, tells me that the first ones had a metal clanker which made a lot more noise, the second year they went to the nylon one to quiet it down some.

It was used in Kalifornia as a signaling device--to locate a buddy or in my case to signal SCUBA class that I found something and wanted them to congregate around me.

They were discontinued as I understand because of fear of weakening the metal from prolonged repetitive pounding in a small space. I would suspect it was from poor sales response

SDM

There was a metal version and a plastic one.

I never understood why the audio reserve never caught on in scuba. They are widely use in in industry and firefighting SCBA's. I have a Healthways Scubair Sonic first stage that makes a clicking sound. It will get your attention and can't be inadvertently shut off like a J valve and it self test's every time the tank valve is opened by a brief clicking noise when the regulator pressures up.

Thanks for the input and info. I installed my valve and had the tank filled and tried it out on the "manual" setting. My valve has the later plastic button and I can only imagine that the metal version was quite the loud device as mine makes a lot of noise! One of the women in my office is an enthusiastic diver who is also a firm adherent to the "latest and greatest" school of thought regarding diving equipment and I can't wait to weird her out with this one.