Stratum 1 PTP Grandmaster: CM4 + SR1723U10 (Part 1)
Summary
A practical, budget-friendly guide to building a Stratum 1 PTP grandmaster using a Raspberry Pi CM4 and SR1723U10 GPS module. The article covers hardware, OS setup, a SatPulse + ptp4l + chrony software stack, wiring, common issues, client configurations, and results showing nanosecond- to microsecond-level timing accuracy in a home-lab environment. It also discusses monitoring, topology impacts, and holdover behavior, offering actionable lessons for low-cost, high-precision time synchronization.