Who rates the Commo Sgt?

The Co Commander signs a rating scheme every month. Ask to see a copy. More than likely, the commo NCOIC is rated by the company XO and senior rated by the Co Cdr, just like the supply sergeant.

I would take out the specific of "commo sgt," who would rate any person in "x" spot? In my last unit most of our commo guys belonged to S-6 and were rated by the S-6 NCOIC, a few people we attached down at the company levels, and were usually still rated by the S-6 NCOIC; or if at the company for a significant time, then someone down at the company level. However if said person is in supply (physically works there) then it makes sense to have the supply NCOIC be the rater since they are around the person. If you can justify the case for who the rater is (whether by mtoe position, work proximity, etc) then that person can be the rater.

XO will be your rater at a company level. S6 NCOIC if youre in a BN shop