[time-nuts] TimeHat - GNSS and RTC module for Raspberry Pi time servers

[John Miller]

Hello everyone!
I’m a long time reader, first time writer. Huge fan of the repository of knowledge that you all have created. I hope its okay to share things like this here, if not - admins please remove it. 

Like many of you here I have been using Raspberry Pis as GNSS-disciplined network time sources for a very long time. Early last year I started reading about adding a real time clock module to help when the system is powered down or has to move, and a few months ago I got a number of DS3231SN modules and began testing. They have worked really well, better than I had expected even, but I wanted to make something a bit cleaner than my messy protoboard versions.

I designed a very simple Pi Hat PCB to carry a DS3231SN breakout board as well as a u-blox MAX-M8Q breakout board. In a future revision I plan to make a single integrated Hat that has the components directly attached, but this works as a quick-n-dirty approach that is still tidier than using protoboards. Though they work perfectly well, I do want to make it clear that I do not consider the PCB to be perfect, I have a number of revisions in mind for future versions. I went ahead and got enough parts, hardware, and boards to make twenty complete Hats, and I would like to sell them to anyone who is interested. 

I realize most of you here probably already have a setup like this, but I wanted to share it all the same because I feel that no lab is complete without a stratum 1 time source! I’m selling the Hat (with standoffs, screws, and a GPS/GLONASS puck antenna) for $50 shipped (USPS priority) anywhere in the US, but I will ship internationally as well for whatever the true cost is. For an additional $10 I will include a 16GB Class10/U1 microSD card pre-configured with DietPi, chrony, and GPSD.

I have more information on my site, here:
https://millerjs.org/timehat <https://millerjs.org/timehat>

Thank you for reading, and have a great week!

Regards,
John M.