Here is a a C Audio RA3001 fixed. Stuck in protect. Two MOSFETs blown on Channel 1 and also three small signal transistors shorted.
- Checked all fuses. .. all fine.
-Identitified blown MOSFETs on channel 1 , removed them. Measured as a resistors! Shorted and not open!!
BF423x2, BF422 and two MOSFETs blown.
Not sure what would cause all this to blow like that!
Pic is with three MOSFETs taken out. One was good though.
- Checked all fuses. .. all fine.
-Identitified blown MOSFETs on channel 1 , removed them. Measured as a resistors! Shorted and not open!!
- Pull out the rail fuses for both channels.
- switched back on via dim bulb, still stuck in protect..
- start checking all the signal transistors and diodes, visual check on board too, this takes time and concentration not to miss any...found three shorted transistors (One was a full short across all leads)
- replaced transistors, checked and checked again, fired up on dim bulb. Comes out of protect , hooray.
- drain filter caps, insert fuses, fired up and all fine and out of protect still. Just need to replace the two blown MOSFETS.
BF423x2, BF422 and two MOSFETs blown.
Not sure what would cause all this to blow like that!
Pic is with three MOSFETs taken out. One was good though.
