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Commercial Auger spectrometers are not always suited for direct Vð measurement,
therefore the user may have to modify the setup with a terminal of artificial middle point of the cathode.
Another way is to find Vð by considering the voltage drop across the cathode.
The calibration is performed in the following manner.
1. The sign and value of the voltage Víàê is measured on the cathode terminals with the normal operational current
through the cathode, while the Vð voltage is turned off.
2. The source of Vð is then turned on and the voltage is measured between the common electrode of
electron energy analyzer and the cathode's terminal to which the Víàê sign was referenced.
The real voltage is equal to Vð.real= Vð+0.5Vinj, taking into account the sign of Vinj.
3. The voltage  , corresponding to the maximum
EBE current on the analyzer's exit is measured. For this,
the modulation magnitude is set to  = 0.5 V and the derivative of
the EBE line is recorded.
Changing Và, the zero signal is achieved (this corresponds to the maximum EBE current on
the analyzer's exit).
The value of is measured on the control terminals of the scanning unit
after turning off the voltage.
The calculated ratio  allows to adjust the scale of the digit-to-analog
converter of the scanning unit.
If the converter's error (for example, 1.4% E) is unacceptable, then the value of E is calculated with the
formula (5.1.3) having the calibration error.
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