Flipping open the front panel reveals a knob that allows one to switch
between NTSC 'video' and umatic 'dub' inputs. The 'dub' input is a direct
wire to the umatic play deck. In theory this wire provides higher quality
input than composite. In practice this isn't noticeable, so we tend to
leave it on video.
Notice also that when you turn the knob, the visual feedback of which
input channel you've selected is shown on the front of the panel,
so you'll have to make an effort to see what's going on. (Lovely
UI design...)
The power switch is also hidden behind that same front panel, as shown
in the diagram.
