DCF77 Time Sync: How Does it Work | by Dmitrii Eliuseev | Dev Genius
How to build a DCF77 HID USB real-time clock (dcf77-hid-usb-rtc) for usage with Linux systems « Adafruit Industries – Makers, hackers, artists, designers and engineers!
Homebrew DCF-77 Synthesizer
DCF600USB: DCF77 Radio Clock for the Universal Serial Bus (USB) – Welcome to Al Mamaas Trading
DCF600USB: DCF77 USB Radio Clock
NTP Server via DCF77 on a Raspberry Pi | Weberblog.net
Connect" to an atomic clock in space! GPS, DCF77 - Electronics-Lab.com