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12.6.1.2 Measures
In expert mode, it is possible to display measures.
Level: measurement of the signal‟s amplitude at the cursor.
Delta : measurement of the amplitude between the two cursors
Power: automatic measurement of the digital carriers‟ powers
C/N : automatic measurement of C/N
Automatic Power measurement
Positioning of the reference level
Search for the noise before and after the cursor location
Calculation of the area between these two limits
Display of the value
Automatic
C/N
measurement :
Positioning of reference level
Search for Maximum peak level
Search for noise level
Display of level difference
Performing a manual
C/N
measurement :
To minimise the appliance’s noise:
Program a reference level as low as possible (greater dynamic range).
Measurement :
for an AM modulated analogue video carrier, select
Max
mode
for a digital carrier, select
MaxHold
mode
position the cursor on the carrier (in the middle for a digital carrier)
shift to
Delta
Ref
) on the highest point
shift to
MaxHold
and move the cursor to an area with no carrier (Noise)
C/N is displayed at the top and in the middle of the screen
