Tektronix MTM400 - Manual (Page 98)

Stream View
3-50 MTM400 MPEG Transport Stream Monitor User Manual
Figure 3-15: Stream view - PCR graph - PCR inaccuracy
The MPEG-2, DVB and ATSC standards specify that PCRs must be within
±500 ns of the actual transport rate. By default, the scale is set to ±500 ns. If the
Inaccuracy in any of the displayed PIDs is greater than ±500 ns, the y-axis is
drawn to show the complete range of values as full scale.
The Maximum PCR Accuracy Error can be adjusted for all PIDs as follows:
ƒ
Tests screen Î 2.4 PCR Accuracy parameter (right-click) Î Max PCR
accuracy error.
For individual PIDs:
ƒ
PIDs screen Î
Test:
select PCR Accuracy Î individual PID parameter
(right-click) Î Max PCR accuracy error.
ƒ
Right-click on the graph and set the limit for each PID.
PCR Arrival
The PCR Arrival graph provides a display of the time interval between successive
PCRs. The interval is displayed on the y-axis. By default (with the View Limits
checkbox enabled) the y-axis scale shows the conformance thresholds for the
DVB, ATSC or MPEG-2 standards.