That is a Data General 6053, aka Dasher D2, terminal, with a trackball spliced in place of the number pad. The D2 was introduced in 1977, same year as the Apple II.
DG story is fascinating. Founded in 1968 by ex DEC engineers. Annual sales of 1B in 1984. But then started losing to DEC's own VAX.
VAX is it's own ball of worms - the designers of VMS, the OS, ended up at Microsoft designing Windows NT. But a bunch of VAX customers ended up up installing this weird thing they got on tape from a friend instead of VMS, called 'UNIX' which confused DEC - why would you want a VAX without VMS?
And now half of everyone that's reading this on a desktop is doing so on either iOS, macOS or Android (UNIX or GNU variants) or Windows (Windows NT successor).
Obligatory plug for "The Soul of a New Machine", written by Tracy Kidder about Data General and the drive to introduce a new computer a couple of years after this terminal was introduced.
