My Stratum-0 Atomic Clock
3 days ago
- #gps-timing
- #precision-oscillator
- #atomic-clock
- O-1's reliance on GPS signals makes it vulnerable to drift from UTC if GPS is unavailable, highlighting the need for a more stable oscillator for O-2.
- Atomic clocks serve as highly stable frequency sources, with costs varying widely from expensive large units to more compact commercial models, all beyond the author's budget.
- DARPA's initiative led to the development of chip-scale atomic clocks (CSAC), such as Symmetricom's SA.45s, which are compact and integrated with GPS for precision timing.
- Jackson Labs Technologies integrated the CSAC with a GPS-disciplined oscillator (GPSDO), enabling O-2 to maintain microsecond accuracy relative to UTC even without GPS signals.
- O-2 uses similar software to O-1 but interfaces with the JLT GPSDO via level-translated serial and GPIO connections, functioning as a stratum-1 NTP server on the local network.
- The project, though costly at thousands of dollars, provided valuable learning experiences, with both O-1 and O-2 repurposed as decorative clocks in the author's home.
- Acknowledgements include gratitude to reader Fazal Majid and Jackson Labs Technologies, along with references to repositories and sources for further information.