Thanks, I wasn't familiar with the jargon or the electronics.
The original post said "might" but it seems that's exactly what cell sites use (GPSDOs).
The original post said "might" but it seems that's exactly what cell sites use (GPSDOs).
The WWV and WWVB atomic clock radio stations have 1Hz reference frequencies that might be stable enough to be your 1PPS reference if you designed your GPSDO to accept an external 1PPS.