[ntp:questions] Re: Looking for time sync hardware supported under Linux for under $400?

Terje Mathisen terje.mathisen at hda.hydro.com
Wed Jan 18 13:41:56 UTC 2006

Tim Keck wrote:

> Richard B. Gilbert wrote:
>> sunblok_$ ntpq -p
>>     remote           refid      st t when poll reach   delay   offset 
>> jitter
>> ==============================================================================
>> *GPS_ONCORE(0)   .GPS.            0 l    4   16  377    0.000   
>> 0.001   0.001
>> There are other GPS receivers that will work quite nicely; one sells
>> for around $85 US.   Be certain to get one with a serial (RS-232)
>> interface (the USB interface does not work well in timing
>> applications).  Also be certain to get a receiver designed for timing
>> applications.  Many GPS receivers are designed for navigation and it
>> is generally not possible for a receiver to do both timing and
>> navigation well.
> Maybe I'm confused, but aren't the delay, offset, and jitter in
> milliseconds, indicating (here) 1 microsecond offset and jitter?

You're right, ntpq works in ms, so this GPS-based ntp server is a
regular member of the us club. :-)


- <Terje.Mathisen at hda.hydro.com>
"almost all programming can be viewed as an exercise in caching"

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