Be sure to add me to your favorites list Original Yamaha Service Manual for Yamaha Rack Mount Units. Take your pick of one of 4 different Models. Pick one for: Yamaha DEQ5E Digital Graphic Equalizer, or Yamaha FMC1 Audio Format Converter, or Yamaha PLS1 Programmable Line Selector, or Yamaha Y20 Active Servo Processor rack mounted units. Choose ONE original Yamaha Service Manual. This is an original Yamaha service manual booklet, with specs, panel layout, dimensions, block diagram, parts list, circuit board diagrams and more! These are all in very good to near like new condition and you can select whichever model you need above. Thank you for looking and please check out my Store! 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!