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SDS2000X HD Service Manual
5.5
To Verify Time Base Accuracy
This test verifies the time base accuracy of the oscilloscope.
Time Base Accuracy: |Frequency Error| < 20 Hz
Note:
20 Hz is the initial accuracy limit of measuring the 10 MHz input. If the oscilloscope has been
used for a long time ( e.g. > 1 year ), the error caused by aging should be added to this limit. Refer to
the datasheet for the aging spec.
Steps:
1. Connect the selected channel of the oscilloscope to the 9500B, as shown in
2. Set the oscilloscope vertical scale to 100 mV/div.
3. Set the timebase of the oscilloscope to 1 ms/div.
4. Set the Memory Depth to 2 Mpts.
5. Set waveform of the 9500B to sine, amplitude to 600 mV, and frequency to 10 MHz.
6. Check if the trigger ( hardware-measured ) frequency which is on the top right of the screen is in
the range of 9.999980 MHz to 10.00002 MHz.
Figure 10
7. Disconnect the test connection.