This AV receiver repair, a Yamaha RX-V450, was completed on a fast turnaround for a local radio producer who needed it in time for a show. It’s got 6x85W channels and more inputs and outputs than you can shake a stick at.
Although I’m well versed in solid state electronics, this is the first AV receiver I’ve worked on, because most of my work is on musical instrument amplifiers.
The fault was with the power supply and is a known design flaw with the otherwise reliable unit. Over time, power surges can damage a 600V capacitor that resides in the soft start circuit. This might sound surprising when UK mains is 230V, but audio equipment should be designed to cope with 1kV or 4.5x the rated mains voltage to withstand surges. I replaced the device with a 760V capacitor, which was the biggest part that would fit in the available space. I added epoxy glue to prevent the larger part becoming a vibration risk.
The amp was dropped off on the tuesday and the repair completed by the thursday. Just one hours work, with a short break for 24h turnaround on the new part.
The repair was completed within the first hour and returned quickly to the customer, who then brought me two other AV receiver repairs! He’d not been having much luck with them!
If you have an AV receiver repair, please let me know and I’ll see if I can help.