Dolby LM100 Broadcast Loudness Meter User's Manual

Measurement Screen Cycles
4.3.4 Units of Measurement
The unit of measure for digital signals depends on the selected measurement type:
• EBU R 128 measurements are expressed in units of LUFS.
• ITU‐R measurements are expressed in units of LKFS.
• Leq(A) measurements are expressed in units of dBFS.
Analog measurements, by default, are expressed as dBu. Analog measurements are
expressed as dBr if the analog calibration setting is not 0 dBu. RF measurements are based
on a relative scale (expressed as dBr) referenced to 100 percent modulation of the
monophonic sound carrier (25 kHz peak deviation).
4.3.5 Level Meters
The level meter display provides a more familiar PPM‐style meter for each
input channel. Figure 4‐11 shows an example. The meters have an instant attack time and
a constant decay of 12 dB/second, ±2 dB/second. Each channel signal is identified at the
bottom of the screen. The scale is displayed on the left side and represents LKFS, dBFS,
dBu, or dBr, depending on the input signal type and processing mode.
Figure 4‐11
Figure 4-11 Level Meter Displaying a Dolby E 7.1 Input
Press Enter to zoom in on the upper portion of the scale.
4.3.6 Metadata Status
The metadata status menu enables you to check the settings of key metadata
parameters in either a Dolby E or Dolby Digital input stream.
4.3.7 Digital Input Status
The Digital Input Status menu indicates whether a digital input signal is locked. If
it is, the menu also displays the sample rate, validity bit status, and individual
channel‐status parameter values.
4.3.8 Error Statistics
The Error Stats menu provides error‐related information for the LM100, its input
signals, or a digital input stream.
The Error Condition display provides information regarding current errors that are
preventing the unit from processing the selected input correctly. Two common error
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