Monroe Electronics ISOPROBE 279, Инструкция по эксплуатации

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I. Speed of Response:
1. Check that the probe to test plate spacing is still 1/8” (3,2mm).
2. Set the gain pot, front panel recessed, for about midrange.
3. Connect the oscilloscope to the rear panel output connector.
4. With the 279 in standby, STBY/OPER switch out, check the range of the ZERO 2 pot on the front panel
meter. It should swing plus and minus with a total of about 10V. Zero the front panel meter with ZERO 2.
5. Push the operate switch and then zero the front panel meter with the ZERO 1 pot on the front panel.
6. Apply a repe1kV pulse to the test plate.
7. Adjust the gain pot, the integrator gain pot (R54) and the oscilloscope controls until a critically damped step
response between 0% and 100% is observed. Rise and fall times from 10% to 90% should be 2.5ms or
less.
8. Repeat for +2kv. The 10% to 90% response time should be 3.5ms or less.
9. Repeat for +3kv. The 10% to 90% response time should be 4ms or less.
10. Check the response to negative steps in a similar manner. Switch to standby.
J. Noise Check:
1. Set the probe to test plate spacing to 0.005” (0,13mm).
2. Reduce the gain to just up from counter clockwise. Switch to operate.
3. Pulse the test plate with +100 volt pulses.
4. Adjust the gain and oscilloscope controls for a critically damped transient response.
5. Replace the oscilloscope with an rms voltmeter. Noise is typically 0.3mV rms.
K. Output Calibration:
1. Connect the rear panel output connector to a DVM
2. Adjust ZERO 1 for zero volts on the DVM and the front panel meter.
3. Slowly apply voltage to the test plate until it is pre3.000kV.
4. The DVM at the output 3.000V

0.1%. Adjust R5 if necessary to meet this condition.
5. The front panel meter should in3000

0.1% LSD.
6. Repeat steps 3 through 5 using –3000v.
7. Check calibration at

2kV.
8. Remove the test equipment and replace the cover. This completes the adjustment procedure.