kb8tq@n1k.org said: > To get the accuracy into the 1 ms range on WWV, you would need a pretty good > idea of the path length between you and WWV. Dave Mills has a program to compute delays. * By default it prints out a summer (F2 average virtual height 350 km) and * winter (F2 average virtual height 250 km) number. The results will be * quite approximate but are about as good as you can do with HF time anyway. * You might pick a number between the values to use, or use the summer * value in the summer and switch to the winter value when the static * above 10 MHz starts to drop off in the fall. You can also use the * -h switch if you want to specify your own virtual height. What's the height difference between night and day? This was google's first response. https://opensource.apple.com/source/ntp/ntp-136/clockstuff/propdelay.c -- These are my opinions. I hate spam.

Hal Murray wrote: > > kb8tq@n1k.org said: >> To get the accuracy into the 1 ms range on WWV, you would need a pretty good >> idea of the path length between you and WWV. > > Dave Mills has a program to compute delays. > > * By default it prints out a summer (F2 average virtual height 350 km) and > * winter (F2 average virtual height 250 km) number. The results will be > * quite approximate but are about as good as you can do with HF time anyway. > * You might pick a number between the values to use, or use the summer > * value in the summer and switch to the winter value when the static > * above 10 MHz starts to drop off in the fall. You can also use the > * -h switch if you want to specify your own virtual height. > > What's the height difference between night and day? > > This was google's first response. > https://opensource.apple.com/source/ntp/ntp-136/clockstuff/propdelay.c Hm, this file is part of the standard NTP source code package available here: http://support.ntp.org/bin/view/Main/SoftwareDownloads Martin