If it has a dome, it's the SPQ-9A, not the B. The B never has a dome. Never ever ever
Ok. I dont know lots about radars/subsystems etc, which is why all I know is learnt off the ships I find out about. I just saw the diagram which Colombamike posted which labeled the dome on top of the mast as SPQ-9B. This was the assumption here.
Right now, atop the pole just aft of the SPQ-9A is an old drawing of a TACAN unit.
Sorry, I thought that the small dome on top of the mast was the TACAN unit. Thanks, I'll put the new one in too.