kaosun Publish time 2021-02-02 15:16:01

1: Door switch and laser switch measured working.
2: 9V input working, 5V for CPU working.
3: Pressing PLAY, a POWER ON signal will be sent to power DC_DC unit. If the unit works flawlessly, it outputs +5V, -5V and controlled 9V.
4: You can download the service manual from out website to have the detail of the DC_DC unit, it will help you replacing all burnt components.
5: When the DC-DC unit is fixed, directly apply 9V, GND to it, connect a 1K resistor between 9V and ON/OFF terminal, you can measure +5V, -5V and 9V from each terminals of the unit. After that, restore the unit back to the D50 to test reading.

kaosun Publish time 2021-02-03 13:32:23

It seems it's less likely to be repaired due to PCBburnt.

electronomad Publish time 2022-02-14 09:39:08

Hi. Sorry if it was asked before.
I'm currently in possession of D-5 & D-50 with similar problems. Both have failed IC802 and CP-301 (DC-DC conv)
CP-301 on D-5: P/N 1-464-378-14. Pins 2 & 6 are short (Q3 B985 is short, adjacent inductance overheats)
CP-301 on D-50: P/N 1-464-378-13. Pin 2 is sort Q3 - diffrent one - short & blown and can't be id'd and smd diode (?) beside it is also short & blown.
Strangely but none of the D-5 service manuals in circulation has details about CP-301.
Could you please share some info about it like schematics, active components?
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