Fluke 5820A, Руководство оператора

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Front Panel Operation
Calibrating the Voltage Amplitude on an Oscilloscope
4
4-11
4-18. Using
u
and
a
The
X
and
a
keys cause the current value of the signal to jump to a pre-
determined cardinal value, whose amount is determined by the current function. These
keys are described in more detail under the descriptions for each function.
4-19. Displaying the Output Error
When you edit the output value in the Voltage or Marker mode, the Control Display
shows the difference between the reference value (the value you originally entered) and
the edit value (the value shown in the Output Display), displaying error difference in
parts per million (ppm). This allows you to edit the output such that the UUT displays the
expected value and thus give an indication of the UUT accuracy.
ref= +10.00000 V
err= -30.0 ppm
f f f f f
For example, an edited difference of .00030 volts for an output of 10.00000 V represents
0.00030/10.00000 = 0.000030, or 30 parts per million. The sign is negative (-30.0 ppm)
because the output necessary to display 10.00000 at the UUT shows the UUT is reading
below the output value. When the reference is negative, the error sign is relative to the
magnitude. For example, if the reference is -10.00000V and the output display is
-10.00030, the error is -30 ppm.
4-20. Resetting the Calibrator
You can reset all parameters in the Calibrator to their default settings at any time during
front panel operations by pressing the
o
key on the front panel.
After resetting the Calibrator, press
l
to reconnect the signal output.
4-21. Calibrating the Voltage Amplitude on an Oscilloscope
Calibrate the oscilloscope voltage (vertical) gain by applying a dc or low frequency
square wave signal and adjusting its gain to meet the height specified for different voltage
levels, as designated by the graticule line divisions on the oscilloscope. The applied
signal from the Calibrator is in Voltage mode. The specific voltages that you should use
for calibration, and the graticule line divisions that need to be matched, vary for different
oscilloscopes and are specified in your oscilloscope’s service manual.