Hello everybody,
I'm quite new in Electronic and arduino, so I'would like you to help me a little 
I want to create a sensor wich tell me the volume of watter of a container. To do so, I would like to use a watterproof ultrasonic transducer to measure the distance of the watter level.
I found a sensor : A-18P20 (http://www.ekulit.de/fileadmin/Bilder/produkte/ultrasonic/700620%20A-18P20.pdf) but I really do not know how it works. I try to find out the datasheet but I didn't find a one wich tell me how to use it.
If you can help me ?
Regards,