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by amluto 1115 days ago
> If you want to overcomplicate it you could put rPi into it and sync the 50Hz clock to NTP

That’s ridiculous! Buy a little GPS-disciplined oscillator and either scale the PPS output up to 50Hz or use a PLL to derive 50Hz from the oscillator output :)

1 comments

Just use a pll to derive 50 from 60. Problem solved.
The GPSDO will also give you correct time of day and unwavering frequency. I used to have one set up at home to feed my test equipment a 10 MHz reference.
If you're powering 50/60Hz clock you won't be setting time remotely on that easily
But how do GPSDO work? Is GPSDO susceptible to metastability?
GPS is a system for distributing time first and a means of computing position second.

A GPSDO is typically a PLL that uses the recovered timebase as a reference input and will have an incredibly slow loop filter. It can be outrageously highly damped and stable.

Such clocks are the basis of the cell network and have made doing client handoff between towers almost easy. The hard part is operating through GPS denial (mostly due to weather).