Hi everyone,

I you have faced this particular situation before or have an idea of how to
solve it, please let me know:

Our Europa 20/20 has developed a peculiar problem. If the electron energy
is set by way of the software to be -90V for example, the source monitor
shows that the electron energy is actually different than -90V. This
problem becomes increasingly worse as the electron current is increased. At
first I thought that this is a result of a failing filament but I replaced
the filament and the symptoms are still very strange. Note that the
following measurements (made by the source monitor) occurred with an
electron energy setting of -90V:

When electron current is 50uA, electron energy is  -89.3V (should be -90V)
when electron current is 100uA, electron energy is -87.1V (should be -90V)
When electron current is 200uA, electron energy is -78.9V (should be -90V)
when electron current is 300uA, electron energy is -72.6V (should be -90V)

Simultaneously another strange result occurs: With the ion repeller set at
zero volts, the source monitor reads the ion repeller to be -6.5V. Only
very occasionally (approx. 5% of the time) does the source monitor read the
ion repeller to be Ov.

Thank you for reading this and possibly offering some suggestions.

Myles Stocki
University of Saskatchewan
Canada