The Morse Beepy is a circuit I designed to be simple and cheap enough for kids and adults to use as a first soldering project, but powerful enough that they could have fun with it. In fifteen minutes, it can be soldered together and programmed to beep and blink your name or secret message in Morse Code.
I tried to keep the cost as low as possible, so I didn’t put a switch in. The circuit board has holes in the right place for a battery holder, but I’m using wires and some binder clips I had laying around. The battery is glued to a backer card so it doesn’t get lost, and the backer card has a broach pin glued to the back for attaching to clothing.
It’s a very basic circuit, just giving power from a coin cell battery to a microcontroller, and connecting the microcontroller to an LED and a piezo buzzer. The microcontroller is an Atmel ATtiny85 programmed using the Arduino development environment.
It uses the following parts:
- CR 2032 Battery
- Battery Holder
- ATtiny85-20PU (standard voltage) or ATtiny85-10PU (able to run on less voltage, thus lasting longer)
- DIP Socket
- Piezo Buzzer
- Red LED
- Custom Printed Circuit Board
I designed the circuit boards myself, and had them manufactured by OSH Park. You can order more of them through the link above. Like the other links, though, I’m not making money from this, I’m just sharing my work and sources to help other folks make stuff.
You can find my code on GitHub. You will see the functions for making dots, dashes, spaces between letters, and spaces between words. The code also contains a bunch of power-saving stuff that might be scary to a beginner, but it’s only necessary if you want days of continuous usage. I’ll keep tweaking the code for clarity and power consumption.