Digital Analysis (QAM View OPT4): Constellation Mode
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CONSTELLATION Main Screen Features
From the CONSTELLATION Main Screen (Fig. 9-15) you can
• view a graphic depiction of the signal
• examine MER and BER data
• select closer views of the impairment
• edit the modulation format and symbol rates
• access the QAM Level display.
Fig. 9-15 CONSTELLATION Main Screen
The SDA will automatically attempt to lock-on to the QAM signal of the
designated channel (or frequency). Lock errors may result from a variety of
conditions, including improper unit configuration or cable connection.
Connect the cable to the digital port on the unit before using any of the four
digital modes.
If initially unsuccessful, the following error message will appear:
“ERROR … Signal Unlocked! Confirm Connection to Dig Port. Retry.”
Press this soft key to retry to lock onto the QAM signal. This key
will appear in the lower right corner of the screen when lock
errors occur, otherwise the key will remain blank.