Introduction: Burping Piggybank

About: Music: my profession for over 40 years... Electronics: my beloved hobby always.

Feed this piggybank with a coin and it will thank you with a nice burp. The heart of this project is PIC12F683 microcontroller (by Microchip). Sound data is stored in its 2K flash program memory. Sound data bytes are read from memory and are shifted left 8 times to one output pin at 23uS intervals. A simple RC lowpass filter reconstructs the original audio signal.

Step 1: Watch the Video

Step 2: The Piggybank

I built this project in a whey protein (1 Kg) container.PC board, speaker and coin-sensing switch are mounted on the lid.

Step 3: Schematic

Step 4: Circuit Operation Details

Step 5: PC Board Download Link

Step 6: Coin Actuated Switch

Switch is made with copper /aluminum /tin foil.

Step 7: Switch Mounting

Step 8: Lid

Battery(3 AAA or 3AA cells) are lodged in a separate plastic box

Step 9: Components List

Step 10: Basic Flowchart

Step 11: Piggybank

Step 12: Watch the Video. Thank You!