This comprehensive service manual provides detailed technical information and repair procedures for the Yamaha RX-V3800 and DSP-AX3800 AV receiver and AV amplifier. The manual covers various aspects of the devices, including the front and rear panels, remote control panels, specifications, internal view, disassembly procedures, firmware updating, and self-diagnostic functions. It is an essential resource for qualified service technicians who need to understand the internal workings of these units and perform repairs efficiently.