TLDR; Picked up for parts cheap, intent was to steal the tube for a green Macintosh Classic (completed). Can I fix the rest?
This is what the machine should look like. It goes by many names like Olivetti M18, Cordata (Corona Data Systems) PC-400 or PPC400-XT.
But mine was missing the drives, the keyboard, the "bottom" keyboard carrying tray, and the front contrast/kb panel. I noticed the tube appeared to be the same size as a Macintosh Classic, so I purchased it for cheap to transplant the tube into a Mac. So, before I removed the tube, I wanted to see if the tube worked. I powered it on and the PSU fired up and the fan started. No beeps and no smoke. I did notice the CRT had a faint glow at the end of the tube internally, so I hoped it was good. After transplanting the tube into the Mac Classic, it did in fact work. So then I thought, "Can I repair the rest of this 8088 to full functionality?" I have been looking around on the internet and not finding a whole lot of technical info. Some random photos from sellers on eBay and such. When I realized I was missing the front contrast knob, it dawned on me that is likely why there was nothing displayed on the tube! A closer look at the motherboard revealed a broken pin, so I know this beast was abused.
Tube ready for transplant.
This is the front panel after some disassembly.
My data plate:
I have an old IBM Model M terminal keybaord, with a 5pin DIN-240, so I may see if I can get that connected. My best guess is a 10K pot for the contrast. I have already started recapping the analog board. The motherboard has very little dust on it. It does have a ton of bodge repairs (like this untested one on eBay).
Bottom only has one repair.
I only see one electrolytic cap on this motherboard. Do I need to replace any of the solid capacitors? Nothing smoked when I powered it on.
The motherboard says Corona Data Systems even though the front cover says Sperry.
Some of the chips on the top have been removed and sockets were added. Sketchy looking solder job on the back.
And I found this area that I have to verify is an intentional cut or possible screw damage from one of the feet having too long of a screw in it.
If anyone has any schematics or maintenance manual, it would be much appreciated.
This is what the machine should look like. It goes by many names like Olivetti M18, Cordata (Corona Data Systems) PC-400 or PPC400-XT.
But mine was missing the drives, the keyboard, the "bottom" keyboard carrying tray, and the front contrast/kb panel. I noticed the tube appeared to be the same size as a Macintosh Classic, so I purchased it for cheap to transplant the tube into a Mac. So, before I removed the tube, I wanted to see if the tube worked. I powered it on and the PSU fired up and the fan started. No beeps and no smoke. I did notice the CRT had a faint glow at the end of the tube internally, so I hoped it was good. After transplanting the tube into the Mac Classic, it did in fact work. So then I thought, "Can I repair the rest of this 8088 to full functionality?" I have been looking around on the internet and not finding a whole lot of technical info. Some random photos from sellers on eBay and such. When I realized I was missing the front contrast knob, it dawned on me that is likely why there was nothing displayed on the tube! A closer look at the motherboard revealed a broken pin, so I know this beast was abused.
Tube ready for transplant.
This is the front panel after some disassembly.
My data plate:
I have an old IBM Model M terminal keybaord, with a 5pin DIN-240, so I may see if I can get that connected. My best guess is a 10K pot for the contrast. I have already started recapping the analog board. The motherboard has very little dust on it. It does have a ton of bodge repairs (like this untested one on eBay).
Bottom only has one repair.
I only see one electrolytic cap on this motherboard. Do I need to replace any of the solid capacitors? Nothing smoked when I powered it on.
The motherboard says Corona Data Systems even though the front cover says Sperry.
Some of the chips on the top have been removed and sockets were added. Sketchy looking solder job on the back.
And I found this area that I have to verify is an intentional cut or possible screw damage from one of the feet having too long of a screw in it.
If anyone has any schematics or maintenance manual, it would be much appreciated.
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