[time-nuts] Four hour cycle in GPS NMEA jitter

[Chris Albertson]

Wow.   350 nS.  I had not been following this for the last few years.   It
seems the ARM is a simply CPU with much more predictable interrupts timing.


One might ask way you'd need such good internal timing.   What got me into
this years ago was scientific data acquisition.  I wanted to time stamp the
data.   So I had a Linux based PC connect periodically to the Internet
using a dial-up phone modem and run NTP.   It worked well enough.    A GPS
receiver at $10,000 each was out of the question.



On Mon, Mar 20, 2017 at 5:06 PM, Gary E. Miller <gem at rellim.com> wrote:

> Yo Chris!
>
> On Mon, 20 Mar 2017 15:19:25 -0700
> Chris Albertson <albertson.chris at gmail.com> wrote:
>
> > I've only hear of 1 uS being broken with hardware.
>
> A Raspberry Pi can get down to a Standard Deviation of about 350 nano
> seconds
> using NTPsec..
>
> https://blog.ntpsec.org/2017/02/01/heat-it-up.html
>
>
> RGDS
> GARY
> ------------------------------------------------------------
> ---------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
>         gem at rellim.com  Tel:+1 541 382 8588
>
>             Veritas liberabit vos. -- Quid est veritas?
>     "If you can’t measure it, you can’t improve it." - Lord Kelvin
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-- 

Chris Albertson
Redondo Beach, California