[ntp:questions] Re: distance to dcf77 transmitter: how to set the fudge?

Richard B. Gilbert rgilbert88 at comcast.net
Wed Jan 26 21:58:49 UTC 2005


Folkert van Heusden wrote:

> Am I right that when I want to tell ntpd that it has to take care of 
> the distance to the dcf77 transmitter that I have to do that like this?
>
> # DCF77 receiver
> # "Der DCF77 Sender steht in Mainflingen (50 0 Nord, 09 00 Ost), etwa 
> 25 km sdstlich von Frankfurt/Main."
> # http://www.maporama.com/
> # Mainflingen: 50 1' 54" , 9 1' 33" 50.0318 , 9.026
> # Gouda/2804 RR: 52 1' 37" , 4 42' 15" 52.0272 , 4.7044
> # http://www.fcc.gov/mb/audio/bickel/distance.html
> # -> 374.766km
> # speed of light: 299 782.458 km/s
> # delay: 1.25012652ms
> server 127.127.8.0 prefer mode 14
> fudge  127.127.8.0 time1 0.00125012652
>
> I ask this question as suddenly the offset for my DCF receiver 
> sky-rockets:
>
>      remote           refid      st t when poll reach   delay   offset 
> jitter
> ============================================================================== 
>
>  GENERIC(0)      .DCFa.           0 l   77   64   16    0.000  
> -246.13  11.484  <---
>  keetweej.intran 130.149.17.8     2 u   71   64   66    0.063    
> 0.488  23.017
> +auth1.xs4all.nl 193.79.237.14    2 u  139  256   17    8.006  
> -19.688  0.428
> *ntp1.NL.net     .GPS.            1 u  135  256   17   18.812  
> -17.445  0.527
> +ntp3-rz.rrze.un .DCFp.           1 u  135  256   17   26.414  
> -16.742  0.266
> +sombrero.cs.tu- .PPS.            1 u  135  256   17   25.625  
> -16.648  1.997
>  time.windows.co 192.43.244.18    2 u  194  256    7  178.229  
> -23.918  8.905
>  time1.apple.com 17.254.0.49      2 u  130  256   17  165.664  
> -19.072  0.834
>  clock3.redhat.c .CDMA.           1 u  132  256   17  188.132  
> -16.833  0.369
>
>
> Folkert van Heusden
>
> Op zoek naar een IT of Finance baan? Mail me voor de mogelijkheden!
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I think your offset of -246.13 milliseconds is several orders of 
magnitude too large to be accounted for by propagation delay.   
Something else is wrong!



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