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RE: Online atomic clock

> For the APRS crowd... does any one have a clue how to 
> discipline the PC 
> clock from GPS?? Sounds interesting!

Some software wil do that for you.  Just need to do a Google search. :)
Also, need to ensure that the GPS has the appropriate output with the
appropriate accuracy for your needs as processing issues can cause jitter -
I did read a long dissertation on GPS timing accuracy a while back.  While
GPS units have extremely high accuracy internally, timekeeping wise, the
question is whether they are able to present the timing information
accurately to the outside world.

> FWIW, I use Tardis 2000/K9 (the Doctor Who fans will appreciate it!) 
> Tardis is an NTP client... gets the time from an NTP service, 
> as well as 
> a server, serving the time to other PCs on your LAN. K9 is the 
> client-only app which runs on the LAN PCs. Both will run as a 
> service on 
> Win2k, tardis has a 1K memory footprint, K9 similar.
> There are Linux versions!

On Linux, I simply run ntpd.  ntpd is the real, full blown NTP server.  It
will sync off an external time server(s) and/or a local reference (e.g. GPS
or atomic clock).  In addition, it can provide NTP services across your LAN
for simpler clients to get high accuracy time info with less network jitter.

If I recall, Tardis actually uses SNTP, which is a cut down version of NTP
that is a bit less accurate.
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