22-08-2025, 03:25 PM
(This post was last modified: 22-08-2025, 03:33 PM by Radio Fixer.)
Things have moved on. I checked everything I could withunpowered measurements. Having one of those LCR ESR testers was a big help. All caps came out with OK values amd ESR.
Next step was to buy some new STR A60535 chips from China. About £11 for 5 from a recommended supplier. Removed the original chip and fitted a 8 pin socket. Put a chip in and powered it up. A spectangular bang and flash which blew a hole in the chip topside.
The original chip had not gone bang even powered up for a fairly long time !
Not sure where to go now as from years ago experience working on SMPs when I semi goes bang it takes other things with it. Perhaps on another day I will make unpowered measurements again and then try another chip and bring it up on a Variac.
Gary
Next step was to buy some new STR A60535 chips from China. About £11 for 5 from a recommended supplier. Removed the original chip and fitted a 8 pin socket. Put a chip in and powered it up. A spectangular bang and flash which blew a hole in the chip topside.
The original chip had not gone bang even powered up for a fairly long time !
Not sure where to go now as from years ago experience working on SMPs when I semi goes bang it takes other things with it. Perhaps on another day I will make unpowered measurements again and then try another chip and bring it up on a Variac.
Gary
