an ATmega328 (for Arduino compatibility), a voice recording playback IC (ISD1730), a cheap 20×4 LCD display, a DCF77 receiver module, and many LEDs. We’re pretty sure that it must have taken ...

So he grabbed a library for Arduino and got to work ... So began his journey to filter, process, and decode the DCF77 protocol. That link goes to the project overview. It will be in several ...