Its a 100% completely different job.
The foundations of both jobs are in electrical and electronic theory but its applications are different entirely.
An ET qualified to be a Reactor Operator (reactor safety, reactor power)
An EM qualifies to be an Electrical Operator (power distribution, loading and unloading electrical generating equipment)
An ET performs diagnostics and calibrations on electronically controlled doo-hickies that directly relate to the Reactor
An EM performs diagnostics, calibrations, and repairs on the electrical ends of motors, generators, lighting systems, basically everything electrical not directly related to Reactor control and reactor safety.
An ET and EM to qualify on many of the same watchstations (Electrical Operator, Throttleman, Auxilliary Electrician Aft, Shutdown Reactor Operator, Reactor Technician, and also Engineering Watch Supervisor later on)
The real difference is the Reactor Operator qualification and what kind of maintenence is performed.
An EM gets really dirty. An EM owns most of a sub's electrical equipment.
