Be sure to add me to your favorites list Original Roland HP-300 / HP-400 Electronic Piano Service Notes Manual Booklet, 1983 This is an original Roland service manual for the Roland HP-300 and HP-400 electronic piano keyboards. It is an original service manual in very good condition, complete and extremely detailed, from 1983. With specs, exploded views, block diagram, parts list, disassembly, circuit diagrams, schematics and more! Thanks for looking! I have two of these available at this time. 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. Thank you so much for looking! Please check out my Store!