communication underwater

Hello i was wondering What kind of communication to send data under watch about 35 to 50 ft? i have seen some say about 30mhz or so? I would like to look into this for a future project.

That's a surprisingly difficult one. Can you use a cable?

I know you want it wireless, but I ask again; Can you use a cable?

Reply #4 (or maybe #5, I'm guessing) will have some bandwidth requirement. Can you use a cable?

Wireless is what preferred If possible.

Maybe use audio? Slow of course, but you haven't said what data rate you need?

Radio isnt possible, at least not for hobbyists. Ultrasonics would stand more chance.

Hello i was wondering What kind of communication to send data under watch about 35 to 50 ft?

Is google broken in your country?

Hello paul no google ant broke yet from me getting there thought and i did try to search for some stuff But wasn’t sure what to search for i thought i could make this into a arduino project for after the winter time coming up soon. Data is what most likely going to be used not sure about voice yet. as for mauried yes hobbyist like m self not sure on what to use. I’m just trying to help out a friend of mine. he has one of them little floats under water things that was build with 2 motors on each side. he build it. was seeing if we can talk under water with maybe some kind of text message. wasn’t sure if some kind of wireless would work or really needed to be cable. I thought being on cable could limited him moving around.

Hello richardtheboffin I'm not sure what data rate is needed to do something like this is why I'm asking in here in this post what maybe we can use. we welcome all suggestions.

hello morgan if go on cable maybe a option but if can do wireless might be better i know being on cable is better fast speed better transfer rate. I know being on wireless is a little slower. I have heard stuff at 20hz that is used for underwater talk. But i think that is licensed. Not sure if it is 20hz to 30hz or 20mhz to 30mhz.

When thinking about underwater communication remember the following: “Radio waves do not travel very far at all in water and sound waves travel very well in water, undermost circumstances.”

Go Here

Thank you all for the help. Wwbrown that site help me to think about a lot of things i haven't thought about yet. As for using cables for test i think that will do the trick for now for testing things into can figure out what to do next.

This might help: https://en.wikipedia.org/wiki/Communication_with_submarines.

Paul

Hello Paul_KD7HB thank you for that information yes that help me to understand what i would need to think about again thank you.