Re: Help with clock division question.

From: Dbowey (dbowey_at_aol.com)
Date: 12/06/04 

Date: 06 Dec 2004 06:11:26 GMT

k8jlf posted:

<<
>That doesn't sound like any protocol I've seen used. Perhaps you are talking
>about a "frame slip" which can happen if one terminal end is experiencing
>clock/sync problems.
>
>All central offices synchronize their digital equipment to a source traceable
>to a Stratum 1 clock. In practice you will normal never see a frame slip
>unless that link is severed and the backup link to a second Stratum 1 clock
>is
>also dead. The days of hierarchical sync between offices is long gone.
>

Ok, while we're on that subject, what does the stratum 1 clock source generally
consist of? What stratum would timing derived from GPS generally be regarded
as? How about a rubidium clock as found in some cellular base stations? (I have
one of these that I was thinking of trying to set up as a timing source for my
lab.) >> 

--
Stratum 1 is an atomic clock having aq bunch of requirements; I believe the
frequency stability is 1 part in 10E-12.
Many Telco timing systems use GPS as a Stratum 1 traceable source for
synchronizing a local Statum 2 or 3 clock.
Don

Relevant Pages

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