Looking for Honking 1st stage as in the old Scubapro design....

[danvolker]

In 1981 SCUBAPRO made an accessory that could be added to the first stage. The device was called the “Sonic Adapter” and its purpose was to give the diver an audible alarm when their air dropped to around 600 PSI.

I would like to use something equivalent to this for a Surface Supplied Air system...a tank held on a paddleboard, and a Brownie Kayak hose going down 20 or 30 feet. While I can check air frequently after an hour and a half or so, and certainly could do a free ascent if the tank was to run OOA, the honking alarm would be the slickest solution.

Does anyone have a source for this type of adapter?

 

[redacted]

The Scubapro "honker" is part of (or attached to) a first stage and requires both an HP and an LP connection. I suspect this would be quite difficult to adapt to a surface supplied air system in a way that the submerged diver could hear it. The Mk5 Sonic which might be adaptable as I believe it is an attachment (First) would require an HP connection from the 1st stage to the diver in addition to the LP hose. BTW, mine honk around 400psi as long as you breath hard enough (not 100% reliable) but I beleive that could be modified if necessary.

Actually, you could probably adapt the much more easily obtained Mk7 rather than the Mk5 Sonic attachment if you are willing to run the HP hose and disable the piston so the 1st stage function will be provided by the 1st stage at the surface.

How "Rube Goldberg" are you willing to go?

 

[danvolker]

The Scubapro "honker" is part of (or attached to) a first stage and requires both an HP and an LP connection. I suspect this would be quite difficult to adapt to a surface supplied air system in a way that the submerged diver could hear it. The Mk5 Sonic which might be adaptable as I believe it is an attachment (First) would require an HP connection from the 1st stage to the diver in addition to the LP hose. BTW, mine honk around 400psi as long as you breath hard enough (not 100% reliable) but I beleive that could be modified if necessary.

Lets say for the sake of argument, that I have a 3 foot cable running from a grommet in the nose of the board, to the scuba tank( which is in the water), and the kayak hose runs from the tank near the surface, to the diver 20 feet below....the tank stays by the surface with the paddleboard.....the 1st stage is in the water, so sound transmission from the 1st stage should be as it was in 1981

What I am going for is the hp gauge ( if this is the noise maker rather than the 1st stage as I thought...) is in the water, near the nose of the board....I used to dive with a guy who had one of these in the 90's, and I could hear him honking from much farther away than 20 feet If I can just have the gauge in the water, and dont need the 1st stage submerged, that is going to mean lower drag with the tank remaining on top of the board.....but even with the tank in the water, drag won't be horrible, and this set up is not for high current diving. What do you think?

 

[redacted]

This thread contains a functional diagram I prepared of the honker portion of a Mk7. I know the sound will carry at least 6 feet (and make your buddy laugh so hard he has trouble breathing) and I agree with you it will go much farther. With the Mk5 Sonic, you should be able to separate the 1st stage and the sonic element. With a Mk7, they are together so the Mk7 would have to be submerged.

One other consideration: Once the honking starts, it will continue until tank pressure falls far enough that the oscillator seal stops bouncing back and forth and seals stopping the delivery of breathable gas. I discovered this in my pool when checking what happens as the tank continues to run low. I suspect this occurs as tank pressure approaches IP. In a normal application, the alternate will continue delivering gas but I assume there is no alternate with your concept. As long as you have ready access to the surface that should not be a problem, particularly at the depths you are talking about.

It seems to me like it is worth a try. If you can't find a Mk7 to borrow locally to try it out, I can probably find one.

 

[danvolker]

This thread contains a functional diagram I prepared of the honker portion of a Mk7. I know the sound will carry at least 6 feet (and make your buddy laugh so hard he has trouble breathing) and I agree with you it will go much farther. With the Mk5 Sonic, you should be able to separate the 1st stage and the sonic element. With a Mk7, they are together so the Mk7 would have to be submerged.

One other consideration: Once the honking starts, it will continue until tank pressure falls far enough that the oscillator seal stops bouncing back and forth and seals stopping the delivery of breathable gas. I discovered this in my pool when checking what happens as the tank continues to run low. I suspect this occurs as tank pressure approaches IP. In a normal application, the alternate will continue delivering gas but I assume there is no alternate with your concept. As long as you have ready access to the surface that should not be a problem, particularly at the depths you are talking about.

It seems to me like it is worth a try. If you can't find a Mk7 to borrow locally to try it out, I can probably find one.

I saw the images of the mark 7, but not the diagram...can you point me?
I will ask around and see if someone I know has a mk7.
Thanks!

 

[GillScales]

Is there some reason you cant just use a small(13 cu ft) pony,or spare air for OOA at 20-30 ft.

 

[danvolker]

Is there some reason you cant just use a small(13 cu ft) pony,or spare air for OOA at 20-30 ft.

This is more of a solution to the Surface Supplied issue of not knowing how much air is left...sure you could use a spare air, but I would prefer knowing that the tank has gotten down to 600 psi, meaning it is time to come up...As the surface is only 20 feet away, even a free ascent is a non-issue for a real diver, but there are applications for Tooka use, where it is being used with non-divers and an instructor, and where there can be no chance of an OOA....

 

[GillScales]

Perhaps an old doublehoser with a hookah port like the DA aquamaster,would work if memory serves they start breathing harder around those kinds of pressures,you'd prolly have to make a special harness yourself though.....


Edit: nvm this won't work as the hookah port bypasses the first stage using only LP air source.

 

[redacted]

I saw the images of the mark 7, but not the diagram...can you point me?
I will ask around and see if someone I know has a mk7.
Thanks!

I forgot to include the link: http://www.scubaboard.com/forums/regulators/241172-scubapro-mkvii-regulator.html

Sorry

 

[danvolker]

I forgot to include the link: http://www.scubaboard.com/forums/regulators/241172-scubapro-mkvii-regulator.html

Sorry

Awesome...Thanks!