My current Stratum 1 server is a Raspberry Pi connected with a Garmin 18x LVC GPS receiver. This is a general-purpose GPS receiver which I previously used with a normal x86 server. The good thing is that it has a long cable, which makes it possible to mount the antenna outside, but I now want to replace it with a genuine GPS hat on the raspberry.
Has anyone here experience with good GPS hats? PPS accuracy is important obviously. Are there any GPS hats with an RTC backup clock? The Raspberry isn’t shipped with a clock chip and at startup, it defaults to January 1st, 1970, until the GPS clock has synchronized. It would be nice to start with a plausible time, rather than jump some decades each time the device is restarted.