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Electronics => Repair => Topic started by: geobee on January 31, 2021, 11:13:13 pm

Title: Yamaha RXV663
Post by: geobee on January 31, 2021, 11:13:13 pm

Hi all, this came onto the bench dead. Replaced the usual suspect, the 22Nf cap in the supply. Still no joy, on checking there is no 5 volt supply, lifted the secondary of the standby transformer, and the ac came back up, but in circuit something is loading it down. Checked several components downstream, but cannot point the finger at anything in particular. I have repaired many Yamaha amps, but this one is becoming a real challenge. Any ideas to check would be great. Cheers.

Title: Re: Yamaha RXV663
Post by: mzacharias on February 02, 2021, 04:56:13 pm

https://www.youtube.com/watch?v=cwkx1nuzHug (https://www.youtube.com/watch?v=cwkx1nuzHug)

Yamaha green power supply analysis

Title: Re: Yamaha RXV663
Post by: mzacharias on February 02, 2021, 05:08:11 pm

https://www.youtube.com/watch?v=x8L2vUo7QJ8 (https://www.youtube.com/watch?v=x8L2vUo7QJ8)

waveforms