Bandwidth Test - Rigol DS1074B Service Manual

Chapter 3 Performance Test

Bandwidth Test

The bandwidth test verifies the bandwidth performance of the oscilloscope by testing
the amplitude loss of the oscilloscope under test at full bandwidth.
Specification:
Bandwidth
Amplitude Loss
[1]
[1]
Note : Amplitude Loss (dB) = 20 × lg (Vrms2/Vrms1); wherein, Vrms1 is the measurement result
of amplitude effective value at 1MHz and Vrms2 is the measurement result of amplitude effective
value at full bandwidth.
Test Procedures:
1. Connect the active signal terminal of Fluke 9500B to CH1 of the oscilloscope, as
shown in Figure 3-8.
2. Turn on Fluke 9500B and set its impedance to 1 MΩ.
3. Configure the oscilloscope:
Press CH1 in the vertical control area (VERTICAL) at the front panel to turn
1)
on CH1.
Press CH1  Probe to set the probe attenuation ratio to "1X".
2)
3) Rotate HORIZONTAL
Rotate VERTICAL
4)
5) Press HORIZONTAL
respectively to set the horizontal position and vertical position to 0.
6) Press TRIGGER
4. Output a Sine with 1 MHz frequency and 600 mVpp amplitude via Fluke 9500B.
5. Press Measure  Voltage  Vrms to turn on the root mean square value
measurement function. Read and record Vrms1.
6. Output a Sine with 200 MHz frequency (the setting value is different for different
model of oscilloscope under test; please refer to Table 3-1) and 600 mVpp
amplitude via Fluke 9500B.
Table 3-1 Setting Value of the Oscilloscope under Test
Model
DS1204B
DS1104B
DS1074B
7. Rotate HORIZONTAL
setting value is different for different model of oscilloscope under test; please
refer to Table 3-1).
8. Press Measure  Voltage  Vrms to turn on the root mean square value
measurement function. Read and record Vrms2.
9. Calculate the amplitude loss: Amplitude Loss (dB) = 20 × lg
(Vrms2/Vrms1).
10. Keep the other settings of the oscilloscope in step 3 unchanged and set the
vertical scale to 200 mV/div.
DS1000B Sevice Guide
-3 dB to 3 dB
SCALE to set the horizontal time base to 500 ns.
SCALE to set the vertical scale to 100 mV/div.
POSITION and VERTICAL
LEVEL to set the trigger level to 0 V.
Full Bandwidth
200 MHz
100 MHz
70 MHz
SCALE to set the horizontal time base to 5 ns (the
POSITION
Horizontal Time Base
5 ns
5 ns
10 ns
RIGOL
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