Another Keithley 2000 problem

[Mark Rivers <RIVERS@cars3.uchicago.edu>]

    Folks,

On the topic of the Keithley 2000 we have had 3 failures in the last month.
The failures have all been identical - the display ceases to function, while
the rest of the unit works fine, i.e. it makes valid readings and sends them
to the host computer.  We are quite sure that the problem is radiation damage,
since all of the the meters which failed were used in a white beam station.

Moral of the story: shield your Keithley 2000 meters if used in white-beam
stations.

                                   Mark