Cost effective time servers

Fri Jun 21 11:50:21 UTC 2019

Denys Fedoryshchenko <nuclearcat at nuclearcat.com> wrote:
> On 2019-06-21 14:19, Niels Bakker wrote:
> >
> > Have you tried this?  Because I have, and it's absolutely terrible.
> > GPS doesn't give you the correct time, it's supposed to give you a
> > good 1pps clock discipline against which you can measure your device's
> > internal clock and adjust accordingly for drift due to it not being
> > Cesium-based, influenced by room temperature etc.
> >
> > You're unlikely to get the 1pps signal across USB, and even then
> > there'll likely be significant latencies in the USB stack compared to
> > the serial interface that these setups traditionally use.
>
> I think it depends on recipe you are using.
> Raspberry have low latency GPIO, and some receivers have 1pps output.
> https://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html

And there are tricks for avoiding temperature-related deviations :-)

https://blog.ntpsec.org/2017/02/01/heat-it-up.html

Tony.
-- 
f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/
defend the right to speak, write, worship, associate, and vote freely