Austin's Nerdy Things

If you're looking to setup a GPS-disciplined time-server at home, I highly recommend this writeup: https://austinsnerdythings.com/2025/02/14/revisiting-microsecond-accur… In the author's latest post he also sets up a pi as PTP grandmaster: https://austinsnerdythings.com/2025/02/18/nanosecond-accurate-ptp-serv…

And I wrote one in Python to climb/turn as well! And to navigate to any of the built-in X-Plane navaids - https://austinsnerdythings.com/2024/04/06/adding-track-following-direc… and the first post in the series - https://austinsnerdythings.com/2021/10/15/creating-an-autopilot-in-x-p…

There's even a pretty great autopilot for x-plane post that makes it to HN every now and then! https://austinsnerdythings.com/2021/10/15/creating-an-autopilot-in-x-p…

It is certainly not to the same levels of accuracy as the capabilities provided by the board presented here, but I recently put together a stratum 1 NTP server (there are lots of various instructions online for setting up something like this [0][1]) on my LAN using a Raspberry Pi 4 and a GPS module with PPS output [2]. The setup took a bit of fiddling and experimentation to get working reasonably well (and it still has some glitches when trying to initially sync the time after a reboot), but once it's synced it does track time from GPS very reliably. For anyone who might be looking for a reliable, accurate NTP time server but isn't interested in the hassle of setting up and configuring the hardware/software themselves, there's also this little appliance [3] I am also using that does something very similar at a great price point (no affiliation here; just a very happy customer). I have both my RPi setup and the NTP200 appliance tracking each other on the same LAN, and they generally agree on the time to within single-digit microseconds, which I think is about as good as one can get with any NTP setup on an Ethernet LAN, at least without resorting to more exotic things like OCXOs, hardware timestamping, etc. [0] https://austinsnerdythings.com/2021/04/19/microsecond-accurate-ntp-wit… [1] https://www.jacobdeane.com/iot/2020/building-a-gps-based-time-server/ [2] https://www.adafruit.com/product/746 [3] https://centerclick.com/ntp/

Sigh Yep. Dunning-Kruger effect specimens hammer out puff pieces to get their participation awards. Meanwhile, here's some other articles: NTP: https://austinsnerdythings.com/2025/02/14/revisiting-microsecond-accur… PTP: https://austinsnerdythings.com/2025/02/18/nanosecond-accurate-ptp-serv… https://www.jeffgeerling.com/blog/2025/diy-ptp-grandmaster-clock-raspb…

have a look at this write up: https://austinsnerdythings.com/2021/04/19/microsecond-accurate-ntp-wit… (not usb though -- uses pps)

I think the most interesting thing on this page is the blog post at the bottom of how it was deployed on a VPS using docker compose (https://austinsnerdythings.com/2023/11/01/using-github-actions-to-depl…

I've got a small Raspberry Pi clone set up with a GSP module running chronyd[2], advertised via DHCP as mentioned by GP. Didn't take much time or effort. I also added a RTC module so it could hold reasonable time during power-loss but I haven't had a chance to verify that it works as expected. [1]: https://www.aliexpress.com/item/1005001623104119.html The 7M and M8N are both much better than the 6M, regardless get a module with PPS output pin, not all have it. And grab an active antenna, you'll probably need it. [2]: https://austinsnerdythings.com/2021/04/19/microsecond-accurate-ntp-wit…