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Channel Plans: Setting Channel Plan Parameters

TIP: To increase sweep speeds, a stable audio carrier can

be used as a sweep point.

Sweeping and measuring a scrambled channel is slower

than an unscrambled channel. Add a “SINGLE” type

channel at the frequency of the audio carrier and enable

this channel for sweep. For a scrambled channel, a

diamond appears in the LCD title bar to the left of the

channel-type indicator on most screens.

• Audio Offset 1 (MHz): This setting specifies the audio offset of the

channel. Use the up and down diamond keys or the keypad to edit the

setting and the Enter soft key to begin and end the entry.

• Audio Offset 2 (MHz): This specifies the offset for the second audio

carrier of a Dual channel. Use the up and down diamond keys or the

keypad and the Enter soft key to begin and end the entry.

• Modulation: This setting is used to specify the QAM modulation used.

You can select either 64 or 256 QAM.

• Symbol Rate: This specifies the information rate of the channel. This

rate is expressed in “millions of symbols per second” (Msym/s) and may

be edited in the Digital Summary Mode. The default for 64 QAM is 5.057.

The default for 256 QAM is 5.360. Edits to the default symbol rate should

be made only when more accurate data is obtained from equipment

specifications or further analysis of the signal.

• Standard: Standard refers to the signal standard used. Annex A is used

primarily in Europe, Annex B is used in the US, and Annex C is used in

Japan. If your channel plan is NCTA, the unit defaults to Annex B; if your

plan is PAL, it defaults to Annex A. Your choices are Annex A (DVB),

Annex A (DAVIC), Annex B, and Annex C.

• Spectrum Inversion: Spectrum Inversion designates whether or not the

signal is inverted.

Configuring a Digital Carrier

This section walks you through the process for setting up digital channels in

your channel plan.

NOTE: The SDA now simplifies digital channel setup.

When you’re changing a TV type channel to DIGI or QAM,

the unit automatically sets the frequency to the center of

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