
Description and Basic Operation: User Interface Elements
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Analysis (QAM View OPT4), has more information about
these keys.
• Press LEVEL to check the audio and video levels of a channel
simultaneously, or to check a specific frequency.
• To balance pilot levels, press TILT. Nine selected video carrier levels are
displayed.
• Press SCAN to see absolute carrier levels on a bar graph. All carriers
are displayed.
• Press SWEEP to test CATV system frequency response. Low-level
signals are injected into vacant spectrum areas by the SDA-5500, and
system carrier reference levels in occupied spectrum areas are
transmitted via telemetry to the SDA unit.
• Press C/N to measure the carrier-to-noise ratio in dB on the tuned
channel or frequency, at a preset noise frequency offset above the video
carrier.
• Press HUM to measure low-frequency hum modulation on the selected
channel. You can select to view the measurement in dB or as a
percentage.
• Press MOD to listen to the audio modulation of the tuned channel or
frequency (AM or FM), and measure the depth of modulation on the
video carrier. Depth is presented as a percentage.
• Press SPECT to activate the spectrum analyzer display, and to measure
CSO/CTB harmonic distortions (in conjunction with the designated soft
key).
See Also
½ Chapters 4, Field Sweeping with the SDA-5000, 6,
Measuring System Performance, and 7, Spectrum Analyzer
Mode, describe these modes in detail.
½ These modes are introduced in “Basic Modes of Operation,”
later in this chapter (page 17).
½ Chapter 9, Digital Analysis (QAM View OPT4), covers the
shifted functions of the measurement mode keys.
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