[time-nuts] Re: Allan Deviation of Z3801A

Mike S mikes at flatsurface.com
Wed Jul 27 15:08:33 EDT 2005


At 01:38 PM 7/27/2005, Bill Janssen wrote...
>If anyone has access to specifications  for SONET or SDH the jitter spec. may be
>related to the above "9.8e-13".  I worked on those spec.'s a long time ago
>and don't remember the details but we were concerned about Allen Variance
>for those time intervals.

T1.101 specs long term of 10e-11 for a Primary Reference Source (Stratum 1). Short term jitter can be more, for example MTIE @ 1 second shall not exceed 10.29 ns. The tightest OC-192 jitter tolerance (T1.105.03) is 0.1 UIpp, which would be 0.1*(1/9.95328*10^9), or approx. 1e-11 in a second also, if I've got things correct. OC-768 would be tighter, but I'm sure the 10811 wasn't designed with even OC-192 in mind.




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