Lovely little clock, would benefit from better timekeeping
For Agora clock v2
I've been running this for a while, as wanted something nicer than a 7 segment LCD display in the living room... the E-ink display is very legible even in a dark room and have had no problems with battery life. The main complaint has been the accuracy of the clock, which is not great... my own one has been losing more than a minute a month, which is worse than you'd expect from a cheap Casio wristwatch... the temp sensor seems a bit wasted as isn't used for crystal compensation - I do recognise this would be a fair bit of work to characterise, though.
The nature of the circuit didn't make it easy to try and analyse the tuning, but hopefully I've made a good mod on this front to bring it closer in line with expectations... will pass my findings onto the creator.
Response from dadantech | Jan. 14, 2022
Hi!
I took a deep look on the clock accuracy and how to improve it and a created a project log on Hackaday:
https://hackaday.io/project/165031-agora-clock/log/202205-xtal-tunning
I will now tune the XTAL capacitors on every new clock to be as accurate as possible with this configuration. I think I can achieve +/- 5 ppm. That will be under 15 seconds per month.
