Communicating Underwater - Aquatec Sub Alert

[scubatoys]

I was two to three metres away from my buddy. My voice was high and squeaky, like the helium balloon voice, but it was perfectly clear, as was my buddy's response. Does the increased pressure (10.5 bars) slow down the sound waves so they become intelligible? I'd like to understand the science.

The increased pressure will not affect the speed of sound. Whether at 10 feet, or 150 feet, you're still looking at about about 1 kilometer a second...

If you really have to tell someone something underwater... If you touch your reg to their head... you can get the effect of a bone earphone... and communicate very nicely. Depending who your buddy is... this might look goofy and get some comments when you get back on the boat...

 

[colonelchuck]

What's your thoughts on using the Aquatec Sub alert as a way to communicate? Is it worth the cost? They also now claim that it works out of the water 1/4 to 1/2 mile. Anyone have any experience with them?

I have one which I use very sparingly. It is not super loud, sounding more like you grabbed a duck by the tail feathers and pulled.

I use it for two things:
1. Getting my buddies attention if I really have a problem and I can't simply tap him on the shoulder.
2. When something really super appears and nobody else sees it. For example, last month a flight of eagle rays came swimming by after almost everybody else had gone around the other side of a large coral head. A couple of quick beeps got their attention.

I suspect that over use might lead to violence.

 

[OE2X]

IMHO - it would be better to invest in a great dive light and use that for getting and keeping your buddies attention. We use our lights during day dives to keep track of each other. I won't have my buddy in my field of view as long as I can see their light beam at all times.

If you have to use an underwater noise maker then you are too far from your buddy. It would be better for you and your buddy to develope excellent buddy skills and communication before you start having to use one of these devices. Again in my opinion there is absolutely no need for divers to use this sort of device that can't be overcome by good solid buddy skills.

 

[IlikeItwetPls]

I use one and so do all my buddies. We don't use them to communicate per se, but to get each others attention. I can dampen the sound with a simple twist of a knob. My wife loves her horn too.

 

[jstuart1]

I have a sub duck on my bc. I have only used it once but was glad I had it. This was in Belize and the first dive I had done that was not a drift dive. The DM had said to let him know when you were at 1/2 a tank so we could turn around. My boat buddy had long since taken off and I was at 1/2 a tank. I had been trying to get the DM's attention but he was to busy trying to find things to look at. When I reached 1300 psi I decided it was TIME to get his attention one way or the other so I sounded the duck and it worked. I don't use it as a general communication device because if everyone gets used to it they won't pay it any mind. But it works well if used sparingly.