RIGOL
DS1000B Service Guide
3-16
Time Base Accuracy Test
Specification:
Time Base Accuracy
Specification
±50 ppm
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.
Output a Sine with 10 MHz frequency and 1.2 Vpp amplitude via Fluke 9500B.
4.
Configure the oscilloscope:
1)
Press CH1 in the vertical control area (VERTICAL) at the front panel to turn
on CH1.
2)
Press CH1
Probe to set the probe attenuation ratio to “1X”.
3)
Rotate VERTICAL SCALE to set the vertical scale to 200 mV/div.
4)
Press VERTICAL POSITION to set the vertical position to 0.
5)
Rotate HORIZONTAL POSITION to set the horizontal position to 1 ms.
Tip: To quickly set the horizontal position to 1 ms, you can first rotate
HORIZONTAL SCALE to set the horizontal time base to 50 ms.
6)
Rotate HORIZONTAL SCALE to set the horizontal time base to 10 ns.
5.
Observe the screen of the oscilloscope. Press Cursor
Mode
“Manual” to
turn on the manual cursor function. Measure the offset (ΔT) of the middle point of
the signal (namely the crossing point of the rising edge of the current signal and
the trigger level line) relative to the screen center using manual cursor
measurement and record the measurement result.
6.
Calculate the time base accuracy; namely the ratio of ΔT to the horizontal position
of the oscilloscope. For example, if the offset measured is 1 ns, the time base
accuracy is 1 ns/1 ms=1 ppm.
Test Record Form:
Channel
Test Result ΔT
Calculation Result
[1]
Limit
Pass/Fail
CH1
≤ ±50 ppm
Note: Calculation Result = Test Result ΔT/1 ms.
