Dug out my 25 year old MU80 to play with , and on powering up it came up battery low, then worked as normal.
So did a quick YouTube search and found one which went through how to change it, no great challenge, but it did throw up a question.
The battery is soldered to the board so unsolder 3 pins, put new one in, and jobs a good un. However in my head , the battery is there to power the units memory, so when you disconnect it that memory is lost and that should be all the patches sounds etc in the unit. Therefor the unit should be powered whilst you change it. The bloke in the video obviously did it without the unit being plugged in and all was good at the end, so what does the battery actually do?
As an aside, trying to google Yamaha battery only brings up ones for bikes, boats and generators!
www.maltingsaudio.co.uk
Comments
I haven't looked through this, but it might have a suggestion? https://www.manualslib.com/manual/197068/Yamaha-Mu80.html
Some battery change ideas here https://forums.syntaur.com/t/yamaha-mu80-battery-replacement/2799