Requoting this, not for rep, but because it seemed to me that this new sonogram might provide context for the UP sonogram.
And it seems we might finally have the beginnings of an explanation for the
top left and top-right quadrants of the UP sonogram (find spoiler in body labelled 'The drawing in the spectrogram') -
They are keyed '-I-' and '-II' respectively.
The implication being that the
Unknown Link is responsible for whatever is represented by the top-left part, and the
Unknown Probe does whatever is represented by the top right?