Interesting OSI system

[Steve Gray]

I am a member of TPUG - the Toronto PET User Group. Last night was our annual "repair night" meeting. One of our members, brought in an OSI system he picked up at a second-hand store long ago - for $10! It turned out to be a C4P installed into an original IBM PC case. It had two full-height drives, 505 board, 540 board, and a D&N mem/floppy card with a hand-made data separator, plus... a TOSIE Hacker card almost fully populated! It seemed to have 3 or 4 separate power supplies, and unfortunately it was missing the keyboard. We didn't dare power it on. It was quite the interesting system, so I thought I'd share.

Seems things have slowed down a bit for the summer.

Steve

[Jeff]

Cool. Any photos, by chance?

[Steve Gray]

Yup, here are some:





Steve

[MK14HAK]

Nice construction job by the looks of it. Must weigh a ton!

Raises the question, how best to power up something up like that that perhaps hasn't been booted for for donkeys. ? Variac ? or reform caps individually?

Maybe you should have taken these along Steve: C4P+D&N floppy not working, 2x C4P not working, C1P not working, Superboard not working.

Things certainly slowed here for the Winter! Ill be getting wary of firing up my 8" hardware come summer here with its similar analog supply. Though I have had more of those switch mode RFI caps blow (Apple psus and monitors) than any big analog supply caps ?
Mike

[Steve Gray]

Nice construction job by the looks of it. Must weigh a ton!

Raises the question, how best to power up something up like that that perhaps hasn't been booted for for donkeys. ? Variac ? or reform caps individually?

Maybe you should have taken these along Steve: C4P+D&N floppy not working, 2x C4P not working, C1P not working, Superboard not working.

Things certainly slowed here for the Winter! Ill be getting wary of firing up my 8" hardware come summer here with its similar analog supply. Though I have had more of those switch mode RFI caps blow (Apple psus and monitors) than any big analog supply caps ?
Mike

Those power supplies are scary... I'd just pull the lot out and replace them with one nice large switching supply. I don't even know what the guy is going to do with it... he didn't really seem to know what he had there. I probably should have offered to buy it from him, but that's my problem - I keep trying to buy stuff to make a working system but just get more non-working stuff... I definitely need to repair my OSI stuff rather than buy more.

Steve

[dave]

Hi Steve,

Cool system!

The best way to power up, after inspecting visually for any obvious bad parts, is with a variac, slowly, and check voltages during ramp-up.

Dave

[BillO]

That's the 2nd best use I've seen for a PC case.