This pet bowl opens when the animal with the receiver approaches it and stays closed for all other animals.
Step 1: Circuitry Used
This is a luggage alarm. You're supposed to put the little fob in your luggage and keep the big receiver. The receiver will vibrate and beep if your luggage gets a certain distance away from you
Step 2: Circuity Used
And, since batteries aren't used it's a perfect spot to put the luggage receiver so I can get tothe sensitvity adjustmen without taking the bowl apart.