🚀 go-pugleaf

Does anyone have any idea where I might be able to get a waterproof ultrasonic
transducer?  The type used in fish-finders might do but I would prefer 
something smaller if possible.  I might also be able to use an underwater
speaker/microphone (hydrophone?) that operates in the audio spectrum.

The application will be transmitting computer data through water sonicly, 
ultrasonic components would be prefered because of the higher information
bandwidth possible due to the high frequency carrier.

I have dug through a lot of surplus catalogs but have had no luck so far, if
you know where I could get something like this I would be very grateful

Greg Corson
...seismo!iuvax!kangaro!milo

P.S. For communications use I obviously need 2 of these things...so one of a
kind components won't be of any use.