[Tyler] was looking for a gift for his friend’s one year old son. Searching through the shelves in the toy store, [Tyler] realized that most toys for children this age are just boxes of plastic that flash lights and make sound. Something that he should be able to make himself with relative ease. After spending a bit of time in the shop, [Tyler] came up with the Pandaphone.

The enclosure is made from a piece of 2×4 lumber. He cut that piece into three thinner pieces of wood. The top piece has two holes cut out to allow for an ultrasonic sensor to poke out. The middle piece has a cavity carved out using a band saw. This would leave room to store the electronics. The bottom piece acts as a cover to hide the insides.

The circuit uses an ATtiny85. The program watches the ultrasonic PING sensor for a change in distance. It then plays an audio tone out of a small speaker, which changes pitch based on the distance detected. The result is a pitch that is lower when your hand is close to the sensor, but higher when your hand is farther away. The case was painted with the image of a panda on the front, hence the name, “Pandaphone”. Based on the video below, it looks like the recipient is enjoying it!