Be sure to add me to your favorites list Original Yamaha YDP-S30 and YDP-S30C Electronic Digital Piano Original Overall Circuit Diagram Sheets. Great, original Yamaha set of overall circuit diagrams for the YDP-S30 and YDP-S30C models of electronic digital piano keyboard. This is the large overall circuit diagram, all tucked into an original Yamaha service envelope with holes on one side of it for placing it into a binder if you wanted to do so. Very lightly used and in very good condition. The envelope shows some storage wear. These are original documents from Yamaha, printed in Japan, from 2007. This is a manual or document, this is NOT a piece of equipment or instrument. If you have any questions, I'm always happy to answer them. Thanks for looking! Check out my Store!