> I think it's about time to retire my old former cell site GPSDO. > Technology has improved and I'm thinking of setting up a Raspberry Pi based > ntp server for the local devices. (I also have some spare Pi's, so...)
> Does anyone have any suggestions for a good solid Pi/GPSDO setup and code for > such a purpose? Something like Leo's device but, of course, much cheaper? How nutty of a NTP server do you want? How much of a Linux hacker are you? Do you need a detailed step-by-step guide or are rough hints good enough? There are several varieties of GPS HAT available. Ballpark $50. I think most of them come with good setup directions. There are several/many web pages describing how to set things up. This is the classic. The Raspberry Pi as a Stratum-1 NTP Server https://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html Google for >Raspberry Pi GPS NTP setup< will find many others. --------- That's GPS, no DO. If you have a GPSDO that you like you will have to convert to 3V logic and wire it up: RX, TX, PPS. ---------- Pis up to 3 have their Ethernet connected over USB so there is 125 microseconds of fuzz on the timing. You would have to put your time-nut hat on to notice that. The Ethernet on the Pi 4 has a direct connection. The Pi 3 and Pi 4 come with BlueTooth on the serial port. You have to disable that or setup another serial port. You can use either chrony or ntpsec. You can use GPSD, or go direct with most GPS devices. Pi IO pins are 3V only. Linux changes. Some of the setup descriptions may be old enough to be out of date. There are also minor differences between distros. -- These are my opinions. I hate spam. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe send an email to time-nuts-le...@lists.febo.com