I work for a European repair center that handles a lot of automation and motion parts. What we see for elco's that are over 5 years old (mostly 24 hour operation), is not really that they tend to leak, but that the internal resistance gets a lot higher than when they are new. So the devices become temperature unstable.
Even good quality caps die eventually, so it doesn't really matter what brand you use.
but what for example, when i don't use my MSX1 that much, only one or two hours a month?
my CX5M from Yamaha is about 30 years old and works flawlessly and I am scared about changings caps.
what do you recommend? how many do i have to change? which caps do you suggest ?
IMHO, there are two approaches for the capacitors on MSX machines:
1) Well known troublemakers
In this case, preventive maintenance is mandatory. This is the case of:
any SMD electrolytic capacitor
Yamaha CX5M's C5 capacitor of the power supply
Panasonic branded capacitors
Nichicon PTH mini-elcos (ex: Sony HB-FXDJ/HB-F1XV FM sound distortion)
And PLEASE use good brand capacitors from well known suppliers whenever you replace a capacitor. That Chinese crap or that fake Nichicon bought on eBay/AliExpress will cause problems in no time.
Note: I'm talking about the old Panasonic branded capacitors here, that were not good. The Panasonic capacitors sold nowadays are of high quality because Panasonic bought Sanyo.
Note2: The capacitors used on Panasonic MSX2+ and TR computers are Rubycon, not Panasonic. They probably changed from their own brand (used on MSX1/MSX2 models) because of the headaches they had.
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2) Well known good boys
In this case, it's best to take the "if it's not broken, don't fix it" approach. Because sh*t happens, no matter how careful you are when doing a full recap.
This is the case of:
Rubycon PTH capacitors
Nichicon PTH capacitors (normal size, not the minis)
