VeEX VEPAL CX350S-D3.1, Руководство пользователя

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The Burst QAM mode can be toggled on and off.
Pre-AMP
The CX380S-D3.1 has a built-in pre-amplifier. This amplifier is useful of detecting the noise floor in a return path.
Peak Detector
Can change the Peak Detector setting from 'Peak-Average' (default) to 'Positive-Peak'. 'Positive-Peak' is best suited for
noise floor detection.
Span Power and Power Spectral Density
This feature is available from the Spectrum Analysis Main Menu. Press "Page Dn" and select "Power ON".
Note: Dynamic Range
CX380S-D3.1 has a dynamic range of 60dB with a display range of 70dB. If the received signal level
is higher than the peak of the dynamic range, the RF receiver will be overdriven and results in
unexpected spurious spikes on the spectrum display. It is recommended that should the peak of the
signal is less than 5dB from the top of the display, increase of the attenuation becomes necessary
until the peak of the signal is about 10dB below the top of the spectrum display. The full 60dB
dynamic range upper and lower limits are shown as purple lines horizontally on screen.
Note:
To optimize the Spectrum Analyzer for Noise Floor Detection take the following steps:
1. Go to Setup / Main Menu.
2. Set the 'SA Pre-AMP' setting to 'AUTO'. Thereafter, whenever you enter Spectrum Analysis, as soon as you change the ATTN setting to
< 10 dB, the Pre-AMP will automatically turn ON.
3. Set the 'SA Peak Detector' setting to 'AUTO'. Thereafter, the Peak Detector is always set to Positive-Peak.
To revert back to default settings, change both settings back to 'MANUAL'.
Spectrum Analysis - Setup Main Menu
Spectrum analysis is not overly complicated, but if you are not careful, it is very easy to make mistakes. The following overview provides
simple guidelines to accurately measure the amplitude of analog and digitally modulated carriers.
Spectrum Analysis - Analog Signal