liqmat wrote on 2021-03-27, 16:07:
megatron-uk wrote on 2021-03-27, 16:05:
Trying to track down the source of the screeching in my recently acquired Sharp X68000 Super... I've already replaced the fan in the PSU with a quiet Noctua, which reduced the fan noise significantly (bearings were shot on the original), but the PSU squeals when in use. Which is a shame, as it works perfectly and, otherwise, the system is in tip top condition. It's just the noise that's an issue:
Every electrolytic has been replaced, but common wisdom says to up the capacitance of the two 5600uF filtering caps to 6800uF. So I'll try that.
Such a beautiful system to gaze upon. Very nice!
It has taken the purchase of THREE X68000 systems to get one in a fully working condition; the first two having spent a significant amount of time trying to resurrect (eventually getting one to the point of reliable power on, full recap and bootable... but no keyboard, mouse or joystick IO, making it unusable).
I paid "through the nose" for this one in a guaranteed working condition, and everything I have tried on it has indeed worked: video is crisp, sound is loud and clear, case plastics are virtually unmarked, both disk drives read and write okay, soft power control works... and the PSU works, but is unbearable in terms of the high pitched screeching. If the worst happens and I cannot solve the PSU noise, I'll simply replace it with a modern alternative, since the rest of the system is now known-good.
My collection database and technical wiki: