I have a Yamaha DX7 s that can not boot.
It lights up but it freezes with 88 in led display and squares in lcd.
I have investigated a bit. There is some treads on the internet that suggests that it is caused by a bad 9.4265 MHz Crystal.
I have checked the crystal with my oscilloscope and it is working.
I tried to pull out the EPROM and start the dx7s without it. It reacted å bit different. It had other numbers in the display. I have not checked all the pins on the EPROM.
Can the EPROM go bad?
Has anyone encountered similar problems?