This project make use of a PIC16F628(A) and a DCF77 receiver from Conrad. Optional there is a possibility to connect an electronic gong on it. Every second is on PORTA.1 (pin 18) a pulse from 0.5 second. This signal isn’t necessary for anything, but maybe you want to connect a LED on it, so that these wil blink every second, or a piezo buzzer, so that the clock ticks as an analog clock.
Overall the project is great and someone put allot of work into designing it.
Digital DCF77 clock with LCD and gong: [Link]