2022-01-03 Yamaha RX-V2092 AV Receiver Amplifier repair
I gave my parents an old Yamaha RX-V2092 AV Receiver with a pair of Aaron speakers which was a great improvement over their built-in TV speakers. However, my parents started reporting it turning off intermittently. Every time I visited, it refused to misbehave, as faults of this type too often appear to do.
This last time, it refused to power on for more than about half a second (not a coincidence, see the service manual). I managed to catch an error out of the diagnostics PS PRT: 0% (via holding VCR2 and VIDEO AUX while powering on), which pointed me towards the power supply. And this time, I'd bought my multimeter and DSO (a recently purchased Rigol DS1054Z), and attacked the Amp, checking all the power rails I could find, and sure enough the DC +5V rail looked very dodgy, and I don't think it was the only one. Pulling the board out enough to see the underside, the joints on several of the regulators (UPC4570HA op-amps) attached to the heat-sink looked very, very dry. I remelted those with a dodgy old soldering iron and some relatively thin 2mm flux cored 50/50 solder I managed to find, and sure enough, amp fixed! Success!
