Some useful manuals, service notes & schematics... Most common manuals are available elsewhere on the web so I'll keep this section for the rarer manuals and notes I have that may be of help. I will add to this list regularly...
Groove Electronics M2CV midi to cv converter - here's the very rare user manual, nearly impossible to use without it...
Groove Electronics M4CV midi to cv converter - and here's the even rarer user manual for the rackmount M4CV...
Korg KR-55 Service Manual - Schematics for the Rhythm 55
Powertran Transcendent 2000 build docs - Original 1978 magazine article with full schematics & build guide
E&MM Spectrum Synthesizer build docs - Complete Spectrum build docs from 1982
Roland OP-8 CV Interface Owners Manual - scan of the rare original manual for the CV to DCB interface