Ceyear 4051 Series, User Manual

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8. Specifications and test methods
8.5 Performance characteristics test
681
33) Repeat step 3 ~ 4.
34) Read the mark amplitude. If this value is less than or equal to the indicator value of 4051, record it as the
displayed average noise level within the range from 40GHz to 50GHz into the corresponding test item of
“4051 Record Table”; otherwise, the value is unacceptable.
Average noise display (50GHz
～
67GHz)
35) Reset 4051 and set as follows:
Reference level -30 dBm
Starting frequency: 50GHz
Ending frequency: 67GHz
MarkerAll Markers Off
36) Repeat step 3 ~ 4.
37) Read the mark amplitude. If this value is less than or equal to the indicator value of 4051, record it as the
displayed average noise level within the range from 50GHz to67GHz into the corresponding test item of
“4051 Record Table”; otherwise, the value is unacceptable.
Display average noise (pre-amplifier on)
38) Follow step 1 ~ 34 when the pre-amplifier option is provided and set the amplifier in step 3 as on.
8.5.1.3.3 Residual response
a) Test items
The residual response refers to the discrete response observed on the screen when no input signal enters the
signal/spectrum analyzer.
b) Test procedure
1) Connect the instrument as shown in Fig. 8.14. Reset the 4051 analyzer and connect 50 matcher at the
signal input 50 interface.
Set the 4051 analyzer as follows:
Center frequency: 15.2MHz
Frequency step28.5MHz
Bandwidth=30MHz
Reference level -50 dBm
Attenuator0 dB
Resolution bandwidth: 10kHz
RF gain best sensitivity
2) Turn on the display line and set the noise level at least 6 dB below such display line at -100 dBm. If not,
reduce the frequency span and the resolution bandwidth to lower the noise level. If the frequency span is
lowered, reduce the frequency step to no more than 95% of the frequency span. If the zero frequency
signal leads to a starting signal amplitude higher than -106 dBm, use the knob to adjust the start frequency
point to lower the noise level to under -106 dBm.
3) Record the maximum response frequency and the amplitude value of current trace in B13 of the 4051
Auxiliary Form.
4) If residual response is suspected, press Single Sweep. The residual response will continue to appear, while
the noise peak will disappear. The noise should not be recorded as the residual response.