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I have joined the Osborne 1 club today.

K

Klee

Experienced Member
Joined
Dec 24, 2010
Messages
320
I just got it in, and its in AMAZING shape!!

A couple of scrapes on the top but overall I am pleased.

The only yellowing on it is on one end of one side of the bottom of the keyboard.

It is really not needing a restoration, just a cleaning and disassembly to check everything out before the first power on.

I removed the front bezel and looked inside and it is VERY clean inside with no dust that I can see.

Also no addon boards mounted to the motherboard so its completely stock.

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I'm guessing this is a fairly low serial number.

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Oh and I have the original box and user manual but no floppy's.


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Very nice! and welcome to the club. Just remember they multiply and there is a 1A the Executive and the Vixen. There are disks and other goodies on the bay.
 
Thanks!!

I have to apply some willpower, no more projects after this for a long while.

I should have no problems making my own disks from images.
 
cj7hawk said:
Replace the three mains filter caps in the PSU before testing it.... After that you can replace the rest on-spec... The others probably won't need it.
Click to expand...

That's the plan.

I'm in no rush to fire it up, and will take my time to make sure everything is ok first.
 
I started to disassemble it a while ago.

I have done zero cleaning outside or inside, not even blowing the little bit of dust off.

Two things, first its VERY clean inside and second absolutely every connection is labeled.

Looks like masking tape and ink pen.

Is that a standard practice?

I'm thinking probably this Osborne 1 has been apart before.

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Power supply.

Rifa caps have some cracks in them but have not exploded yet.

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Other caps look perfect, overall the power supply looks very nice.

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I think I will order new caps to replace the the questionable rifa caps finish the disassembly then go over everything, lube the floppy drives then fire it up. I really do not see any major issues.
 
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I do have one question, this power supply has two rifa caps and pictures I have seen of other Osborne 1 power supplys show three, C11 on my power supply is a disc style capacitor not a rifa as I have seen in other pics online and it looks to be original.

Is this a known thing?

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Also it does not look like it has ever been replaced just by looking at the solder on the bottom of the board.

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Well, that one's not in the mains power part of the circuit, so who knows? It's a black swan event :)

Looks nice - An early Osborne 1. Did it only have one plug on the PSU for system power? Newer ones had two - one for the floppy drives. Maybe they had problems with early harnesses and so replaced the harness in later models. I note the extra 12v and 5v lines are missing from yours ( These go to the Floppy Drives ) - Perhaps they had power issues in early models. Some certainly had a load of tantalums soldered to the incoming power lines underneath, which suggests so.
 
Klee said:
I think I will order new caps to replace the the questionable rifa caps finish the disassembly then go over everything, lube the floppy drives then fire it up. I really do not see any major issues.
Click to expand...
They are time bombs....You can remove them and run it without them.
 
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