Circuit for converting digital signals representing color information into analog voltage level signals applied to a monochrome CRT monitor. Digital signals representing color information are applied to first ends of a plurality of resistors (R1 to R4) the other ends of which are connected to a common...http://www.google.com/patents/US4727414?utm_source=gb-gplus-sharePatent US4727414 - Circuit for converting digital signals representing color information into analog voltage level signals with enhanced contrast between foreground and background
