F5-6.EPS

5700A/5720A Series II Calibrator

Service Manual

1 V

Figure 5-6. Waveform at Pin 11 of K2 10 ms Manual background

F5-6.EPS

Figure 5-6. Waveform at Pin 11 of K2

4.Check the 220 μA range of the 220 μA/2.2 mA AMP circuit. Set the Calibrator to 200 μA, standby. Set the external ac reference to 6.4V(±0.1V) at 1 kHz. Using a

DMM, measure the ac voltage at the collector of Q4 and verify it is 2.0V ac ±10%. If a failure is detected, first verify that the 10 kΩ shunt on HR2 is correct and that it is connected to SCOM thought relays K5C, K5D, K10, K13 and the 1.2Ω load resistor

R14 as in Figure 5-8. If the shunt and output switching is correct check Q4, Q5, K3, and the associated components in the 220 μA/2.2 mA AMP circuit.

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Fluke 5720A service manual 6. Waveform at Pin 11 of K2, F5-6.EPS