We have two cats that love to go into the garage. Knowing when they were ready to come back in was always a problem. We decide to set a motion detector by the steps which is triggered when the pets come up to the door. The unit I am currently using was for driveway sensing, and came from Harbor Freight. It is a unit with a receiver for the inside of the house and provide a notifying beep when the detector is set off. An Insteon Wireless detector could also be used to set off a tone device located in the house.
This system works great. We also use sensors at out outside doors which let us know someone is at the door even before they press the doorbell. Outdoor detectors should be place in shaded areas to avoid false triggers from clouds blocking the sun briefly. They also need to be positioned so dryer vents are not in their path.
I believe in freedom for pets, but not if they won't return. Our neighborhood has lots of roaming coyotes. If you allow your pet to roam, then say goodbye.
Stu's Views is Education and Fun. What do YOU want to VIEW today? MathLandia High school mathematics learning fun. Both Stu's Views and MathLandia are free websites that do not sell anything. Saving energy is not always free. Be a world saver.
Please don't PM with questions that can be asked in a forum.