these are the roland TB-303 service notes:

roland.TR-303.schem-1.gif  43k	specifications, knob/ case part no. 
roland.TR-303.schem-2.gif  40k	IC pinouts
roland.TR-303.schem-3.gif  57k	block diagram
roland.TR-303.schem-4.gif 105k	digital schematic
roland.TR-303.schem-5.gif 145k	analogue schematic
roland.TR-303.schem-6.gif  83k	adjustment, view from component side
roland.TR-303.schem-7.gif  69k	adjustment, view from foil side
roland.TR-303.schem-8.gif  47k	vcf envelope modulation, parts list



additional higher resolution scans of pages 6 and 7 are split into left
and right pages. scans by robin whittle (http://www.firstpr.com.au)

roland.TB-303.schem-6-left-150dpi.jpg
roland.TB-303.schem-6-right-150dpi.jpg
roland.TB-303.schem-7-left-150dpi.jpg
roland.TB-303.schem-7-right-150dpi.jpg