U11, Q30, Q31, Q32, and their associated components.

5700A/5720A Series II Calibrator

Service Manual

1 V

Manual background 10 ms Manual background

F5-25.EPS

Figure 5-25. Waveform at TP6

10.Check CH1 SERIES B. Connect an oscilloscope to TP4 (common to TP3).Set the Calibrator to 6.5V dc, operate, and the oscilloscope to 10V/div at 2 ms/div. The oscilloscope should display a signal similar to previously shown Figure 5-19. If a failure is detected, check Q33, Q34, and their associated components.

11.Check CH2 FLOATING. Connect an oscilloscope to U12 pin 7 (common to TP3) and set it to 10V/div at 2 ms/div. Verify it displays a signal similar to Figure 5-26.

Note

The duty cycle may differ from Figure 5-26. At this time just verify the amplitude and a sharp rise and fall time. If a failure is detected, check U12 and its associated components.

12.Check 3V reference. Using a DMM measure the voltage at U11 pin 3(common to TP3) for a nominal 3V dc. If this voltage is incorrect check U1B and the associated resistors on the HR5 Hybrid assembly.

13.Check CH2 FILTER INPUT. Connect an oscilloscope to TP7 (common to TP3) and set it to 2V/div at 2 ms/div. Verify it displays a signal similar to the previously shown Figure 5-20.

Note

The duty cycle may differ from Figure 5-20. If a failure is detected, check

U11, Q30, Q31, Q32, and their associated components.

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Fluke 5720A service manual U11, Q30, Q31, Q32, and their associated components