Be sure to add me to your favorites list Yamaha Service Manual for the PSS-125 PortaSound Keyboard. This is a full service manual, with specs, panel layout, block diagram, dis-assembly procedure, test program, parts list, exploded views, circuit board diagrams and more! Includes: Specifications Panel Layout Circuit Board Layout LSI Data Table IC Block Diagram Disassembly Procedure Test Program Circuit Boards Overall Circuit Diagram Parts List Modify / Circuit Bend it .... or fix some broken features, make it look pretty again or even bring back your PSS from the dead with help from this manual! 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!