Hey guys
I am trying to breathe life back into an AU555, this little thing was sold to me as "working"but sadly is anything but.
Inside is all original as far as I can tell. I have taken her to a local tech who was told me "electrically the amp is in bad shape" and "all the output transistors and drivers should be replaced" I took the amp away deciding what to do and figured what the hell let me dive in myself. I have done loads of research on the net etc on this unit and have now replaced all 4 output transistors (2SD180) with ON Semi MJ21194. After this was done tried powering the amp up on a dim bulb and got smoke from one of the CDC transistors on the main amp board..
uke: So tonight just popped out the CDC8002 and 9002 trannys on the main amp board and replaced with MJE340s and MJE350s. Powered back up and yep smoke comes from same area on the board and the new transistors are hot to the touch on that side after power on for 5 seconds...
Anyways pretty much out of my depth now and thought I would throw this out there and see if anyone had some wize words before I move on to another tech to diagnose the issues.
:help:
I am trying to breathe life back into an AU555, this little thing was sold to me as "working"but sadly is anything but.
Inside is all original as far as I can tell. I have taken her to a local tech who was told me "electrically the amp is in bad shape" and "all the output transistors and drivers should be replaced" I took the amp away deciding what to do and figured what the hell let me dive in myself. I have done loads of research on the net etc on this unit and have now replaced all 4 output transistors (2SD180) with ON Semi MJ21194. After this was done tried powering the amp up on a dim bulb and got smoke from one of the CDC transistors on the main amp board..
uke: So tonight just popped out the CDC8002 and 9002 trannys on the main amp board and replaced with MJE340s and MJE350s. Powered back up and yep smoke comes from same area on the board and the new transistors are hot to the touch on that side after power on for 5 seconds... Anyways pretty much out of my depth now and thought I would throw this out there and see if anyone had some wize words before I move on to another tech to diagnose the issues.
:help:
