Yes, why not as CEPTAM entrance exam is basically conducted for the B.Sc students only for getting a job in DRDO in your respected field.

You can write this exam at the end of 5th Semester or I can say at the starting of your 6th and Final semester.

Basically exams are conducted for these posts:

Post of Stenographer Grade-II, Administrative Assistant – A, Store Assistant – A, Security Assistant – A, Clerk, Asstt Halwai-cum Cook, Vehicle Operator, etc.