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Discussion of precise time and frequency measurement

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Re: [time-nuts] leontp offset?

HM
Hal Murray
Sat, Oct 15, 2016 3:26 AM

the offset of the leontp device from the other clocks has consistently been
in the 9.5 -10.5 range.  since I'm measuring all three sources  from the
same (EL7) computer, I would expect that the offset of the leontp unit to
converge to be in the close neighborhood of the offsets of the arbiters. It
has not converged, instead maintaining the ~10ms offset.

Thoughts?

The delay column shows the same small delay on all 3 boxes.  That pretty much
rules out something strange on the network side.

I would add a few outside clocks.  That might help you figure out which clock
is right/wrong.  (Both Arbiter's could be setup with the same error.)

You might check the antenna cable delays.  (on all 3 boxes)  Somebody might
have typed in the wrong number, ms vs ns or km vs feet.

What sort of setup is LeoNTP?  Is it triggering on the trailing edge of a 10
ms wide PPS pulse?

--
These are my opinions.  I hate spam.

gmx.tallahassee@gmail.com said: > the offset of the leontp device from the other clocks has consistently been > in the 9.5 -10.5 range. since I'm measuring all three sources from the > same (EL7) computer, I would expect that the offset of the leontp unit to > converge to be in the close neighborhood of the offsets of the arbiters. It > has not converged, instead maintaining the ~10ms offset. > Thoughts? The delay column shows the same small delay on all 3 boxes. That pretty much rules out something strange on the network side. I would add a few outside clocks. That might help you figure out which clock is right/wrong. (Both Arbiter's could be setup with the same error.) You might check the antenna cable delays. (on all 3 boxes) Somebody might have typed in the wrong number, ms vs ns or km vs feet. What sort of setup is LeoNTP? Is it triggering on the trailing edge of a 10 ms wide PPS pulse? -- These are my opinions. I hate spam.