[ntp:questions] Local (own site) NTP servers.
g8kbv at nospam.uko2.co.uk
Mon Jul 27 16:33:47 UTC 2009
In article <4a6ade33$0$31039$5a6aecb4 at news.aaisp.net.uk>,
david at ex.djwhome.demon.co.uk.invalid says...
> G8KBV wrote:
> > To get Faros (HF Beacon monitoring program, runs on Windows,
> It looks to me as though that application requires timing to better than
> about 10ms, and probably won't benefit much more below about 2.5ms. I'm
> assuming that they are trying to treat the morse code station ident as
> though it were a code division multiplexing spreading code. The ident
> is at 22wpm. 12 wpm uses 100 ms basic units, so 22 uses approximately
> 50ms units. One wants significantly better timing than that.
> I note that Faros requires special access to the sound hardware -
> presumably it only works with real sound cards, not USB ones. It seems
> to me that you could use any stereo sound card, with very loose
> scheduling requirements if you fed a PPS signal into the opposite
> channel from that used for the off air signal, and used that as a timing
> reference for the off air signal, and to calibrate the sound card
> sampling clock. As it looks like it is closed source, it would have to
> be done by the vendor, or it would have to be re-implemented.
Indeed, it is. I (and one or two others) have asked the author Alex
VE3NEA, but he seems uninterested in implementing any local GPS driven
(for example) time synchronisation. Pitty, considering that the
beacon's themselves are GPS' synched. Hence my interest in getting
something local (on my LAN) working one day, so as to not rely on my
(variable) ISP's servers.
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