[sdiy] Lexicon Prime Time Schematic?

[xamboldt]

I recently came across a broken one of these, an old digital delay  
from Lexicon (the first Prime Time, model 93). OK, it's not a synth,  
but it has a CV input and an internal VCO, so it's close enough. :)

Does anyone have a schematic or service manual for this thing, or know  
where I can get one? Upon opening it, the most apparent thing wrong is  
that it's missing one IC, U22. There also may be a card missing, but  
without the schematic/service manual, I'm can't tell if that's just a  
spot for memory expansion.

Thanks for any help you can provide,
Chris