Ceyear 4051 Series, User Manual

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4. Operating Instruction
4.1 Function operation guide
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filter has better selectivity than the Gaussian filter and therefore is more capable of distinguishing two signals
with unequal amplitude.

Configure filter bandwidth manually
The filter bandwidth can be selected manually by activating the [Filter BW] through 【 BW 】 key on the front
panel.
The 4051 Series Signal/Spectrum Analyzer has four ways to describe the Gaussian filter bandwidth: 3 dB and
6 dB bandwidth of filter, pulse bandwidth and noise bandwidth. Wherein: the noise bandwidth refers to the
bandwidth when the rectangular filter is used to pass through the noise signal power with same peak gains.
The pulse bandwidth refers to the bandwidth when the rectangular filter passes through the pulse signal power
with same peak gains.
When the electromagnetic interference test is executed, the 6 dB bandwidth or pulse bandwidth is applicable
to describe the filter bandwidth; when the noise-like signal or channel power is measured, the noise bandwidth
is applicable to describe the bandwidth.
When the parameters of [Filter BW] are changed, the filter bandwidth actually used will not be affected, and
the Series Signal Analyzer only uses another way to describe the filter bandwidth and display it on the screen
information area. E.g., the 3 dB (1 kHz) bandwidth and 6 dB (1.41 kHz) bandwidth, equivalent noise
bandwidth filter of 1.06 kHz and equivalent pulse width filter of 1.48 kHz.
Caution
The filter type and the filter bandwidth
When the 4051 Series Signal/Spectrum Analyzer selects the ―flat top" for the filter type, the filter bandwidth
cannot be selected and the [Filter BW] turns grey.
4.1.2.4 Set parameters of amplitude/Y Axis
The section mainly describes the meaning of the parameters corresponding to 【 Amplitude/Y Axis 】 and
provides the operation guidance. The
【
Amplitude/Y Axis
】
key and the corresponding setting soft menu are
used to set the amplitude reference and display range of active window of Series Signal Analyzer, which is
available in multiple measurement modes and functions. In the spectrum analysis mode, they are mainly used
to set the reference level, attenuator, display range of level and unit of amplitude of the Series Signal Analyzer.
The functions may vary in other measurement modes or functions, please refer to the corresponding manual.
1) Parameter description of 【 Amplitude/Y Axis 】
The menus corresponding o the
【
Amplitude/Y Axis
】
key on the front panel include [RefLevel],
[Attenuation], [Scale Type Log Line], [Scale/Div], [Auto Scale], [Y Axis Unit
▶
], [Ref Level Offset], [Ampl
Cor ▶ ].
[RefLevel] refers to the maximum signal acceptable by the measurement hardware on the premise that the
measured results are guaranteed. The input level exceeding the above the maximum signal may distort. In
such case, the information bar of 4051 Series Signal/Spectrum Analyzer will display the prompt information
of ―IF Overload‖.
[Attenuation ▶ ] submenu is mainly used to control the gain distribution of the RF reception hardware of the
Series Signal Analyzer and the includes such parameters to be set as mechanical attenuator, Elec Attenuator,
step of mechanical attenuator and maximum mixer level. Only the options of Elec Attenuator are configured
properly will the settings of relevant Elec Attenuator become effective.
[Scale Type Log Linear] is used to select the trace data in display area to be linear or logarithm. When the
―Logarithm‖ is selected as the type scale, the graticule of Y Axis is segmented in way of logarithm and the top
graticule is corresponding to the reference level (when the reference level offset is set as zero), while the
numbers corresponding to other Y axes can be set through amplitude scale. When the ―Linear‖ is selected as
the type scale, the graticule of Y Axis is segmented in linear and the top graticule is corresponding to the