[ntp:questions] CHU time source?

David Magda dmagda+trace040726 at ee.ryerson.ca
Thu Dec 30 17:31:37 UTC 2004


Hello,

Reading a bit about CHU service offered by the NRC up here in Canada
and NTP.

I borrowed a Sun Sparc 5 (Solaris 8) in relation to other work I'm
testing, and was curious whether it's as simple as plugging in a
shortwave radio into the microphone jack and telling NTP (4?) about
it with 'driver 7' (127.127.7.x). I'm in Toronto, Ontario which is
about 400km away from Ottawa (source of the CHU signal).

Has anyone used CHU? Is the driver still useful for an Internet
connected machine? Perhaps a a backup in case the network goes away?

Also, how accurate is the WWVB signal in this part of North America
(Niagra Falls / Buffalo / Rochester, NY area).

I'm currently getting accurate results from a couple of servers I'm
using:

     remote           refid      st t when poll reach   delay offset  jitter
*wxo-svr2.cmc.ec NAVOBS1.MIT.EDU  2 u  775 1024  377   33.066 1.081   1.280
-dense.utcc.utor tyme.gw.utoront  2 u  728 1024  377   34.534 4.188   0.121
-time.nrc.ca     tic.nrc.ca       2 u  767 1024  377   16.695 4.900   0.440
+sue.cc.uregina. tick.ucla.edu    2 u  726 1024  377   54.044 2.434   3.118
+stjohn.mainecoo prowlingtabby.m  2 u  723 1024  377   88.350 0.308   0.108

ntpdc> kerninfo
pll offset:           0.0010811 s
pll frequency:        -118.629 ppm
maximum error:        0.52004 s
estimated error:      0.004167 s
status:               2001  pll nano
pll time constant:    10
precision:            1e-09 s
frequency tolerance:  496 ppm
pps frequency:        -118.972 ppm
pps stability:        0.000 ppm
pps jitter:           0 s
calibration interval: 4 s

This is a FreeBSD 4-STABLE box running on a generic P3-700 machine.

Thanks for any info.

(P.S. This is mostly an academic excerice, but I'm always willing to
experiment, learn, and try new things.)

-- 
David Magda <dmagda at ee.ryerson.ca>, http://www.magda.ca/
Because the innovator has for enemies all those who have done well under
the old conditions, and lukewarm defenders in those who may do well 
under the new. -- Niccolo Machiavelli, _The Prince_, Chapter VI



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