Reply 40 of 48, by bogdanpaulb
Rolling wrote on 2023-04-07, 09:04:Hi guys, […]
Hi guys,
sorry for digging up the old thread, but i guess my problem is quite similar...
I'm trying to resurrect an Olivetti PCS 286 machine at the moment and the power supply stands in my way. The fuse was blown, i already changed the two Rifa/ Kemet 0.47 Uf caps and put in a new fuse. At least there's no explosion anymore. When turning on, i hear a click (but no fan) and can measure the following voltages (while connected to mobo with hdd) .
1° BROWN: +5.06V
2° BROWN: +5.06V
1° BLACK: GND
2° BLACK: GND
RED: -0.19V (shoud be +12V)
BLUE: -12.10V
WHITE: +5.06V (shoud be -5V)RED and WHITE seem to be wrong, but i don't know if that's a problem created by capacitors or any other component. I just measured the bridge rectifier, which seems to be ok.
Maybe anyone has a hunch?
Your problem should be in the selected part of the psu pcb. You can post some pictures with yours and the selected area, front and rear, maybe i can assist you further.