The start of a new project. A Sony DTC-P7 Dat (Digital Audio Tape) recorder on the bench for repair. I found this unit at a thrift store in an unknown condition. I took the unit home and tested it. It was not working (as is aspected). The tape did run smooth and everything worked. But most of the time no audio output and when there was audio the sound was distorted.
I opened up the recorder and found many bad surface mount electrolytic capacitors. Because this is a very small recorder there was not much space inside to work so i had to take it apart completely. I replaced all the bad capacitors and did some repair on the PCB that was corroded by the leaking electrolyte from the caps. Now the device is sounding great and working like a charm……exept……
There is still a problem with the muting circuit of the analogue audio. Connected through TOSLINK optical or coaxial digital there is no problem. But analogue audio through the line out and headphone amp is muted after a while. I will dive deeper in this problem in the near future. It has to do with the muting circuitry. Maybe a bad transistor, cap or diode or a bad trace on the PCB. To be continued!
Inside view of the DAT recorder:
Recapping the RF board:
New capacitors in place:
Removing the main PCB:
The removed main PCB:
Damage on the PCB from the leaking capacitors: