Technician was a rank, not a job, though. Details can be found here - http://en.wikipedia.org/wiki/United_Sta ... 42_changes
If you want to mark a model as having such a role then a T rank is how you'd do it. It's basically a rank to do with a specific area of expertise, this could be with a mortar, radio or even a medic with a certain skill or level of training in a field.

