I have a project in mind that would need some range finding under water.
It would require a transponder that is, I believe the term is omni=20
directional,  meaning the ping goes out in all directions.
I have heard that you can make a transducer using a piezo speaker but=20
was wondering if anyone had seen any thing about this.

What it is for is under water ROV.  I can share more details if anyone=20
is interested.

I started this project about 10 years ago but then had a heart attack=20
and had to stop working on it.  I have decided to put this project in my=20
bucket list.  I now live part time in a small
city of Algoma, Wisconsin which is on the shores of Lake Michigan. =20
Every time I see the lake I want to send down my UWROV to explore the=20
lake bottom.

This project will allow me to return to a spot time and time again.

Bob
--=20
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