the unit's output voltage. To reduce common-mode noise pickup, set up the oscilloscope for a differential, two-channel voltage measurement. To reduce normal-mode noise pickup, use twisted, 1 meter or shorter, 50Ω coaxial cables with shields connected to the oscilloscope case and to each other at the other ends. Proceed as follows:

a.Connect the test equipment as shown in Figure 2-5. Operate the load in constant resistance mode (Amps/Volt) and set resistance to maximum.

b.Turn the unit's power on, and turn up current setting to full output.

c.Turn up output voltage to: 7.0Vdc (6023A)

20Vdc (6028A)

d.Reduce the resistance of the load to draw an output current of: 29.0Adc (6023A)

10Adc (6028A)

Check that the unit's CV LED remains lighted.

e.Set the oscilloscope's input impedance to 50Ω and bandwidth to 20MHz. Adjust the controls to show the 20KHz and higher frequency output-noise waveform of Figure 2-6.

f.Check that the peak-to-peak is no more than 30mV.

Figure 2-5. Peak-To-Peak Measurement Test Setup, CV PARD Test

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Agilent Technologies AGILENT MODELS 6023A and 6028A service manual Peak-To-Peak Measurement Test Setup, CV Pard Test