Ceyear 4051 Series, User Manual

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8. Specifications and test methods
8.5 Performance characteristics test
675
Where ΔL refers to the Marker Delta amplitude reading of the 4051 analyzer (dB);
A
ATT
refers to the calibration value of the standard attenuator (dB).
d) Test records and data processing
12) Determine values in results of all test items in B12 of the 4051 Auxiliary Form and fine the positive
maximum error value ΔA
Vmax
and the negative minimum error value ΔA
Vmax.
The absolute values of such
two errors should fall within the range of reference scale fidelity, otherwise, the they will be considered as
noncompliant.
13) Calculate the display fidelity ΔA according to the formula (24) and record it in the 4051 Record Sheet.
8.5.1.2.10 Trace detector mode
a) Test items
The detector mode refers to a way of displaying signal energy. The AV 4051 provides 7 detector modes
including normal, Peak, negative peak, sample, video average, power average and voltage average.
b) Test procedure
1) Rest the 4051 analyzer and enter the second page of the trace menu to access 5 detector modes, including
normal, Peak, sample, negative peak and average (the average detector mode is classified into three types:
video, power and voltage), in which normal mode is the default detector mode.
2) Change the detector mode of the 4051 analyzer to change corresponding trace and display it based on the
set detector mode.
c) Test records and data processing
3) If steps 1 ~ 3 can be properly completed, it means the trace detector mode is normal and meets relevant
requirements. In this case, ―compliant‖ should be noted in the 4051 Record Sheet, otherwise it should be
considered as noncompliant.
8.5.1.3 Dynamic range test
8.5.1.3.1 1dB gain compression
a) Test items
When the input signal level increases, unit circuits of the signal/spectrum analyzer, including the mixer and
the amplifier are working close to the saturation point and the input signal component at such time will no
longer change linearly with the input signal. Usually, the input level 1 dB lower than the input linear value
offset is considered as 1 dB compression point.
Input a low power signal and then a high power signal with frequency interval of 3 MHz into the
signal/spectrum analyzer. Change the power of the high power signal until it causes measured value of the low
power signal to lower to the closest point to 1dB to obtain the power value of the high power signal, which is
also the 1 dB gain compression value.
b) Test equipment
2434/E4418B is recommended for the power meter.
E8257D/1464 is recommended for synthesized signal generator #1.
E8257D/1464 is recommended for synthesized signal generator #2.