Ceyear 4041 Series, User Manual

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Chapter XI Performance Characteristics Test
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input of signal generator, and the RF output of signal generator is connected to the RF input of spectrum analyzer
to be tested. The spectrum analyzer provides the reference frequency for the synthetic signal generator.
2) Set the spectrum analyzer as follows: center frequency: 4 GHz, span : 0 Hz, RBW and VBW: 10 MHz,
minimum settable sweep time: 10 μs, maximum settable sweep time: 600 s, if the above settings meet the
requirements of the item "sweep time range (zero span)" in the 4041 Series Spectrum Analyzer Record Sheet,
mark "
√
", or mark "×."
3) After resetting the 1464C, set the frequency to 4 GHz and power to -5 dBm, [Modulation], [Amplitude
Modulation] [Amplitude Input], [External], [Back], [Amplitude Modulation On/Off], and turn on the amplitude
modulation switch and RF output switch.
4) Make the following settings with soft keys on the Agilent 33250A:
【
Ampt
】
, 1 [Vrms], [Offset] 0 [V], [Output],
and set the output waveform to [RAMP].
5) Set the scale type of spectrum analyzer to linear and peak detection, RBW to 3 MHz, and VBW to 3 MHz.
6) Set
【
Freq
】
on the Agilent 33250A to 10 [kHz]. Set the spectrum analyzer: [Sweep Time] 1 [Milliseconds],
[Sweep Type Consecutive One-time].
7) Set the spectrum analyzer, press
【
Peak
】
and place the marker on the first peak from the left through [Next Pk
Left] or [Next Pk Right]. Press
【
Marker
】
[Detla], press
【
Peak
】
and place the marker on the ninth peak from
the left through [Next Pk Left] or [Next Pk Right]. Read the differential marker value and calculate as follows:
Sweep time error = 100 × ((marker differential reading × 1.25 - preset sweep time) / preset sweep time)% (3)
Record the calculated data at 1ms sweep time of the corresponding item in the 4041 Series Spectrum Analyzer
Record Sheet.
8) Turn off the marker and repeat steps 6 to 7 for other sweep times listed in the record. Set the frequency in step
6 as follows:
Modulation rate = 10/setting of sweep time (4)
11.5 RBW
Description: The RBW indicates that the spectrum analyzer can clearly separate the two input signals. It is
affected by factors such as IF filter bandwidth, phase noise, and sweep time. Most spectrum analyzers achieve the
different RBWs with the different methods such as LC filter, crystal filter, SAW, digital filter, etc.
The output of synthesized signal generator is connected to the RF input of spectrum analyzer. The bandwidth of
spectrum analyzer 4041 is approximately set to 2 times the current RBW (to facilitate the measurement,
bandwidth is subtracted by 3 dB). The output amplitude of tracking generator is reduced by 3 dB to determine the
actual -3 dB point. After the marker reference is set, the output of tracking generator is increased by 3 dB back to
the previous level, and then the sweep starts. The differential marker is used as a measurement value of 3 dB
bandwidth
The readings with the 3 dB bandwidth test function in the 4041 series can be used as test values. The error of span
of 4041 series may introduce a certain error in the RBW accuracy. The error of span is negligible relative to the