CHAPTER I: FEATURES AND SPECIFICATIONS Features, specifications, etc. CHAPTER II: THEORY OF OPERATION Basic operation of the mechanical system, the electrical system and the electrical circuit, and their timing. CHAPTER III: DISASSEMBLY AND REASSEMBLY Procedures of disassembling and reassembling the mechanical system. CHAPTER IV: TROUBLESHOOTING Reference values and adjustments, troubleshooting for image defects, troubleshooting for malfunctions, etc. APPENDICES: Connection diagrams, PCB circuit diagrams. Note: There are each captions for HL-720 and HL-730 730Plus to divide this manual according to the contents. You can fin the captions under the headings. Please pay attention to them On the other hand, the headings have no captions that means the contents are common to HL- 720 and HL-730 730Plus.