Interesting enough, several researches about MZ-80 K PSU failures are related to tantalum caps (four blue ones) issues.
I'm replacing those today; here's hoping!by replacing the blue capacitors which are part of the voltage setting circuit
It was disgusting, like brown tar. The photos are post alcohol, toothbrush and dishwasher...hahaThat gunk is probably just kind of glue used during assembly/soldering.. or whatever was left from anti-vibration silicone/glue
Leaked caps are much more... gross
Yes I wouldn't dare plug it in with the main board connected incase it blew that as well! The PSU was physically removed from the case before I plugged it in...If I look at the schematics correctly, fuse near cables you are talking about is F401, on the +12v rail. Did it blow *after* you removed it from mainboard? Because there is not much there to cause it when it's not connected to anything.
I did notice in this picture on the link posted by hlide that the fuse in question plus the 2 orange wires are not soldered in, while the voltages are being read...a bit odd?
https://www.nightfallcrew.com/13/01/201 ... ly-repair/