Analog Non-Linear Distortion Measurement; Carrier To Composite Noise Ratio Measurement - ADInstruments S7200 Operation Manual

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6.2. Analog Non-linear distortion measurement

6.2.1. Carrier to Composite Noise Ratio Measurement

To measure CCN Ratio with your S7200, you must set-up the video carrier
frequency and noise bandwidth correction correctly in the channel plan editor.
Noise bandwidth is different depending on the channel bandwidth, which
depends on your location. (NA, or EU). NTSC-M system uses 4MHz noise
bandwidth correction. PAL-D system uses 5.75MHz noise bandwidth correction.
Noise measurement bandwidth for different TV standard
Standard
Video bandwidth
Noise bandwidth
Typically, CCN measurements require that system engineers measure video carrier
level (Sync tip of the modulation is the absolute peak level), then remove the
video modulation by shutting down the modulator, or simply remove the
modulation from the carrier, so to allow accurate noise measurement. Of course,
removing modulation will interrupt the service which is not desirable. A better
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S7200 TV Signal Analyzer Operation Manual
I B，G
6.75 5.75
5.08 4.75
Figure 6-12 CCN measurement
K1，L D，K
7.25 6.75
5.58 5.75
M，N
4.95
4.00