Tektronix MTM400 - Manual (Page 157)

Interface Configuration and Interpretation
MTM400 MPEG Transport Stream Monitor User Manual 3-113
EVM (%) (Error Vector Magnitude) Closely related to, and can normally
be calculated from, MER. It is a ratio of 'errored signal vectors'
to maximum signal amplitude expressed as a percentage
(ref: TR 101 290 Annex).
BER (Bit Error Rate) Provides an indication of the Forward Error
Correction workload.
TEFs (Transport Error Flag or TEI transport error indicator) Indicates
the Forward Error Correction failure.
Lock If the interface is able to acquire full lock onto the channel and is
receiving the signal correctly, the
Lock
indicator will light up
green. Red indicates that lock cannot be achieved. Gray
indicates that a signal is not present.
The Settings area of the screen contains the following controls:
Update (s) Allows the period in seconds between samples of the incoming
signal to be set.
Persist Allows the time that the dots persist on the grid display to be set.
The Log area of the screen contains the following controls:
File Constellation data can be written to the file identified in this
field; data is saved in csv format.