hmm, ok looks like Aphex have done a major upgrade of their website since they moved premises!
I have just downloaded the user manual, but it doesn't have any schematics.
I note there are some discrepancies in the drawings contained within as well. One drawing shows the 722 as having 5 LEDs on the right hand side, yet the photo of the 722 on the website only shows 2 LEDs in that position.
The manual makes no mention of the 722 in the table of contents, only mentions the 720 and 723.
The area of the manual dealing with the front panel controls shows a drawing of a 720, with no mention of the 722 or 723.
I think I will have to contact Aphex to find out, as I need more detailed information that is specific to the 722.