Sonar Ranging Module RM400, and the only "response" that I've got from the sonar

[issabel]

Hello!

I have a question. I've tried to use Sonar Ranging Module RM400, and the only "response" that I've got from the sonar it's the one from the image. Do you have any idea why it is not working?

This is the device: http://www.farnell.com/datasheets/1697789.pdf

[system]

You've given us an 800 kB (blurred) image , but no link to the device? :o