I have two nice looking D-66s, but both in the same poor technical condition. When turned on, the display works and nothing else happens. Sometimes the motor spins, but it's completely random. I fully recaped both, cleaned PCB's, checked traces and vias. No results. I'm planning more serious measurements and I'm asking for any hints here.
Small update just for the records. I have successfully repaired both of my D-66s.
During the measurements I noticed a lack of +3.7V on IC502, which led me to Q407 which after checking turned out to be OK, but no +3.7V on the collector. Following this lead I checked a pair of control transistors (Q408) and bingo. Their emitters should be pulled-down via R416 and here I found a break on the trace invisible to the naked eye. This appears to be a weak point susceptible to corrosion as the same issue occurred in both players. I marked the break location in the photo.
This post contains more resources
You have to Login for download or view attachment(s). No Account? Register