Osborne-1 with prototype-based motherboard

Brad H vintagecomputer at bettercomputing.net
Sat Dec 29 18:59:03 CST 2018

I'd love to see a photo of the innards of the prototype if anyone knows
where to find them.  There were 10 built, and someone took a photo recently
enough for it to be of decent quality (the one that appears on
oldcomputers.net).  Someone must have one somewhere.

I think Al might be onto something with the tech manual.  The question is,
how did the revision scheme work?  I have two Revisions noted on the board..
the 2A2011-00 Rev D (in marker), and 3A3005-00 Rev C.   Looking at later
boards like this one:
https://www.flickr.com/photos/eevblog/31731875815/in/photostream/ ... It
looks like the trailing 2 digits on the 2A2011 number changed to either 02
or 20.  So is a 2A2011-00 Rev D and a 2A2011-20 Rev D the same thing?
Don't' know.  

And then other boards used a 3Axxxx-xx number instead of the 2A2001 number.
Kind of confusing.


-----Original Message-----
From: Sam O'nella [mailto:barythrin at gmail.com] 
Sent: Saturday, December 29, 2018 2:48 PM
To: Brad H <vintagecomputer at bettercomputing.net>; General Discussion:
On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
Subject: Re: Osborne-1 with prototype-based motherboard

Maybe too easy but have you asked the seller if they know anything about
it's origins? I'd also guess maybe an employee or it could just be one of
the 6 motherboard types as someone else commented. Pretty awesome though
with the low serial. Thanks also for the blog. I had no idea about the
different designs and cases. 

I'm curious which one I have now. 

Sent from my Apple /////c

> On Dec 29, 2018, at 2:53 PM, Brad H via cctalk <cctalk at classiccmp.org>
> Am just posting this as I am hoping someone out there knows someone 
> who was involved with Osborne back in the day to find out more this 
> Osborne 1 motherboard I found in a low serial O1 I picked up for $100.
> I reached out to Lee Felsenstein on it and he suggested it was related 
> to the boards produced for the 10 prototypes Osborne built, or a 
> derivative of them.  He couldn't say for sure how it ended up in mine.  
> But I was hoping if anyone knows any Osborne experts that might help 
> me on this - it is not currently working and I'm hoping to find 
> schematics, etc to get it going again.  Obviously with the radical 
> differences in layout, the schematics for the production motherboard isn't
terribly helpful.
> I've posted a blog about it here with a picture of the board for those
> curious:  http://bradhodge.ca/blog/?p=1186
> Brad

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