A chirping egg that can contain candy. Great for egg hunts, games or just a fun novelty. Emits a chick sounding chirp at delayed intervals, and is built into any plastic egg that is 2" or larger diameter. The circuit fills the shorter half of the egg, and most of the rest of space is available for candy or prizes. Originally designed for the blind, this little gadget is fun for all and especially when you build several and create a chirping egg basket.
The circuit can be built using a PC card or perf board and is based on multiple oscillators built from a single 74HC05 Hex inverter. Operates on 9V battery. Timing resistors can be varied slightly from the design values to get eggs with their own personality.