Ceyear 4992A, Руководство пользователя

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Chapter VII Performance feature test
109
Average: OFF
4) Record the measurement results of three indicators of the digital voltmeter in Table A.27.
5) Change the output signal amplitude of the audio generator according to Table A.27, and record
the measurement results of three indicators of the digital voltmeter in Table A.27.
d) Test steps of DC measurement mode
1) Change the output of the audio generator/analyzer as follows:
Waveform: DC
Waveform configuration:1V (amplitude)
The amplitude of the DC signal is about 1V.
Connect the signal to the audio/DVM input end of the tested instrument.
2) Change the settings of the digital voltmeter window as follows:
Mode: DC
3) Read the voltage test results. In this case, the effective value, positive peak value and average
value should be the same. Record test results in Table A.27.
4) Change the amplitude of the DC output signal of the audio generator according to Table A.27,
and record the measurement results of three indicators of the digital voltmeter in Table A.27.
23.Oscilloscope (tested if any)
A. Vertical measurement accuracy
a) Test items
The external audio/DVM signal and internal demodulation signal can be tested with the
oscilloscope. In this test, the external input signal is applied as the investigation target and the
output signal of the high-accuracy function generator is used as the benchmark to respectively test
the vertical measurement accuracy of the oscilloscope according to the signal input channel
requirements.
The vertical measurement accuracy of this instrument is 10% (×1 level).
b) Test block diagram and meters
Instrument / equipment:
Function generator (recommended model: Agilent 33250A and Agilent 8903A)
One BNC cable (100cm)
c) Test steps
1) As shown in the figure, connect the instrument, turn on it and warm it up for 30min.
2) First test the measurement accuracy of the audio input signal. Then set the output parameters
of the function generator as follows:
Waveform: sine
Amplitude: 0.2Vp-p
Frequency: 1kHz;
DC bias: 0V
Radio
frequency
output Agilent 33250
Function
generator
Audio/DVM input
4992A
Rradio Test Set
F
ig. 7-13 Connection Diagram of Measurement Accuracy Test of Oscilloscope