HP E42 manual Model 5328A Maintenance

Model 5328A

Maintenance

It is very important that the DAC adjustments be performed after the A and B channels sensitivity adjustment. In this adjustment, follow the procedure outlined on page 12 of the Option 041 Manual but adjust for optimum sensitivity by continuing to decrease the signal generator level below 25 mV rms and adjusting the A12R26, R28 for stable counter displays.

a.Set up the equipment as in Figure 5-2. Set the rear panel address switches on the 5328A to:

Set the 651B test oscillator to 20kHz at a level of 25 mV rms (70mV p-p). Set the 180A oscil- Ioscope A channel for ac coupling and 50 mV per division. Verify that the 20 kHz signal into the counter is 70 mV p-p.

b.Disconnect the dc supply for a 0.0-volt dc offset on the input signal. Execute from the key- board of the 9825A the following:

wrt 701, “PF4G5S1S3A379+000*B37+000*R”

Monitoring the 5328A Marker A output on the oscilloscope, adjust A11R21 for a 50% duty cycle in the Marker A signal as shown:

c.Connect the 5328A B Marker output to the B channel of the oscilloscope. Adjust A11R20 for a 50% duty cycle in the Marker B output signal. (The counter has been programmed for COMA.)

d.Connect power supply as in the figure and adjust for a dc level of 2.00 volts (±2 mV) as read on the DVM.

e.Execute the following from the keyboard of the 9825A:

wrt 701, “PF4G5S1S3A379+200*B37+200*R”

(press RECALL on 9825A and simply change DAC voltages as required.)

Adjust A11R18 for a 50% duty cycle on the 5328A B Marker output signal.

Connect the 5328A marker output signal to channel B of the oscilloscope. Adjust A11R24 for a 50% duty cycle on the A Marker output signal.

h.Reconfigure dc power supply for negative voltages and set the voltage for -2.00 volts (±2 mv) o

i.Execute the following from the keyboard of the 9825A:

wrt 7Ø1, “PF4C5S1S3A379-200*B37-200*R”

j.Adjust All R26 for a 50% duty cycle on the A Marker output signal.

k.Connect the 5328A B Marker output to the B channel of the oscilloscope. Adjust A11R17 for a 50% duty cycle on the B Marker output signal.

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