-24 dB Range Flatness Verification
-24 dB Range Flatness Verification
Checks high frequency AC amplitude flatness on the - 24 dB attenuator range. Also checks flatness for the 0 dB atten-
uator range.
1. Connect a precision AC voltmeter to measure the output amplitude as shown below. Connect the BNC cable to the
Wide Band input of the Fluke 5790A.If you are using substitute test equipment, verify that the input impedance is
50 Ω, because load accuracy directly affects measurement quality.
2. Set the precision AC Voltmeter to "Medium, Medium" Digital Filter and Filter Restart.
3. Set the instrument to each output described in the table below and measure the output amplitude with the AC
voltmeter. This will become the reference measurement. Set the output impedance to 50 Ω. Be sure the output is
enabled.
Use
Waveform Generator
Measurement
Output Load
Function
Amplitude
Frequency
Nominal
Error
Q
50 Ω
Sine
0.190 Vrms
1.000 kHz
0.19 0Vrms
±0.0026 Vrms
4. Set the measured value in Step 3 to be the reference value on the AC voltmeter.
5. Set the instrument to each output described in the table below and measure the output amplitude relative to the
source as a percent with the AC voltmeter. Note that the table also lists the output in dB if you are using a power
meter to perform this test.
Use
Waveform Generator
Measurement
Output
Load
Function
Amplitude
Frequency
Nominal
Error
Nominal
Error
50 Ω
Sine
0.190
Vrms
100.000 kHz
100%
±
1.15%
0 dB
± 0.10
dB
50 Ω
Sine
0.190
Vrms
500.000 kHz
100%
±
1.74%
0 dB
± 0.15
dB
Agilent 33500 Series Operating and Service Guide
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