Hi guys, my project is on an ultrasonic motion detector, i m using the circuit from http://kitrus.com/kits.html. but i couldnt get my hands on the 400S series so i m using the 400E series (400ET/R). Obviously my circuit is not working as it should. plzzzz what changes could the change in the tranducers cause.
Also wats the 10M in parallel with the tranducer for.

 

Which of the two ultrasonic kits are you using?

hgmjr