VeEX VePal CX350, Руководство пользователя

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Note:
The red blocks indicate the predefined threshold window for the measurement parameter
The affect of noise or poor C/N on analog video carriers is described below.
Note:
The average power changes depending on the picture content e.g. dark scenes have a higher average power than bright scenes. Using the sync pulses, the carrier is
at its peak power and it does not change from scene to scene; therefore, peak power has become the standard for analog video carrier level measurements. The CX350
measures the peak level for analog carrier.
Analog Carriers - Peak Power Measurement
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7.1.2 Digital Channel Measurements
When testing a digital channel, the unit first tries to achieve digital lock. Once digital lock is achieved, the unit displays the related digital measurements, as well as the
constellation diagram.
Note: QAM unlock
If the unit is unable to lock onto the digital channel, the following icon is displayed. Always ensure QAM
lock is achieved prior to making Constellation and related digital measurements.
SLM button:
The following measurement information is provided for digital signals:
Channel number (defined in the channel table)
Channel frequency (defined in the channel table)
Channel or program name
Modulation type measured
CX350 e-Manual D07-00-037 RevC01 Page 24 of 81