Tektronix MTM400 - Manual (Page 101)

Stream View
MTM400 MPEG Transport Stream Monitor User Manual 3-53
PCR Frequency Offset (PCR_FO)
The Frequency Offset graph shows the difference between the program clock
frequency and the nominal clock frequency (measured against a reference that is
not PCR or transport stream derived).
Figure 3-18: Stream view - PCR graph - PCR frequency offset
PCR Frequency Offset is a measurement of the error in the PCR frequency from
the specified 27 MHz; the MPEG specification sets the limits at ±810 Hz.
The Maximum PCR Frequency Offset can be adjusted for all PIDs as follows:
ƒ
Tests screen Î PCR Tests section Î PCR Frequency Offset (PCR_FO)
parameter (right-click) Î Max PCR overall jitter.
For individual PIDs:
ƒ
PIDs screen Î Test: select PCR Offset Î individual PID parameter (right-
click) Î Max PCR frequency offset.
ƒ
Right-click on the graph and set the limit for each PID.