During a recent one week "Intensive SEM" course that took place in Johannesburg, South Africa, the students came up with a superb cleaning technique that they wished to report upon. The results are, or should be, interesting to everyone who has to clean a cathode assembly! This note was originally posted on MSA's microscopy listserver and generated several replies. I have included more information below in response to these replies.

Often the most time consuming operation during the routine use of a SEM or TEM is the cleaning of a cathode assembly. The procedure, outlined as follows, requires little operator intervention, is free from possible cathode contamination by the cleaning media, and takes comparatively very iittle time