Spectracom SecureSync 1200 User Reference Manual page 552

APPENDIX
Element identification: The "on time" reference point for all elements is the pulse leading
edge.
Index marker (Binary 0 or uncoded element): 20 millisecond duration.
Code digit (Binary 1): 50 millisecond duration.
Position identifier: 80 millisecond duration.
Reference marker: 80 millisecond duration, 1 per 10 seconds. The reference marker
appears as two consecutive position identifiers. The second position identifier or ref
erence marker is the on-time point for the succeeding code word.
Figure 5-64:
Additional information
The beginning of each 10 second time frame is identified by two consecutive 80 ms elements
(P and P
0
for the succeeding time code. 1PPS position identifiers P
0.1 s before 1PPS "on time" and refer to the leading edge of the succeeding element.
536
Element rate: 10 per second.
Position identifier rate: 1 per second.
Reference marker rate: 1 per 10 seconds.
IRIG E time code description
). The leading edge of the second 80 ms element (P
R
) is the "on time" reference point
R
, P ... P (80 ms duration) occur
0 1 9
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