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mwillegal
November 9th, 2012, 05:19 PM
Just a quick update to those that are interested in the SCELBI reproduction project that I've been working on. My goal has been to get a basic set of SCELBI 8H PCBs laid out and fabricated by the end 2012. I'm not sure about having the boards in hand by the end of the year, but the layouts are starting to approach final form. There is still a lot of checking and cross checking to do, but the changes I'm making now are really minor tweaks.

In addition, I've started acquiring some key components. I've bought enough 1101 memory for a fully populated 8H. That is 128 chips, folks. Thinking ahead, I also acquired enough 2102s for a full SCELBI 8B, which I'll be building after the 8H is done. That is another 96 chips. Earlier this week I ordered a small batch 8008s, enough to supply one to everyone who wants a SCELBI board set. Chip prices and availability are much better than I originally expected, which enabled these fairly large purchases. I never thought that I would be able to afford all the SRAM to fully populate a SCELBI with memory. One tip, when it comes to these particular parts, I would stay away from ebay, as prices there are out of whack.

Also I acquired an original SCELBI stock certificate and an original 8H sales flyer from a SCELBI employee, who had saved them for all these years. Both are in outstanding condition. The stock certificate is signed by both Nat Wadsworth and Robert Findley. I have framed those two items and put on display in my den.

regards,
Mike Willegal

billdeg
November 9th, 2012, 06:25 PM
I have a lot of 1103 RAM, too bad its not 1101. I have plenty of 2102s though. I would be interested in a kit is there a web site to follow the project?

mwillegal
November 12th, 2012, 03:28 AM
I have a lot of 1103 RAM, too bad its not 1101. I have plenty of 2102s though. I would be interested in a kit is there a web site to follow the project?

Hi Bill,

I have a SCELBI web page and a blog

http://www.willegal.net/scelbi/the8008andScelbi.html web page

http://www.willegal.net/blog/?cat=16 blog - cat 16 has 8008 related entries

regards,
Mike Willegal

billdeg
December 10th, 2012, 08:27 AM
I have a Scelbi monitor program papertape in the MARCH archives...interested? I will trade the papertape for a Scelbi! And throw in a few bucks.

I will copy and post the source code asap.

billdeg
December 11th, 2012, 04:13 AM
Oops...it's 8080. Never mind. Scelbi put out am 8080 monitor in a book or magazine at some point.

mwillegal
December 11th, 2012, 05:56 PM
Oops...it's 8080. Never mind. Scelbi put out am 8080 monitor in a book or magazine at some point.

yeah, once the Altair came out, the folks at SCELBI realized that there was more money in publishing than computer hardware. They wrote books targeting a variety of early micro-computer systems. I believe that the 8080 monitor you have, was based on the 8008 monitor that they did for the SCELBI.

As far as the SCELBI PCBs layout goes, I'm making slow, but steady progress. I have been going through design review/checking of the various boards. Comparisons of schematics to the DIP chip connections on the layout are almost complete as I have completed these checks on 4 of the 5 boards. I still have to do discrete component checks and tweaks and finally a general review, before sending the Gerbers off for quotes.

regards,
Mike Willegal

mwillegal
January 31st, 2013, 05:32 AM
A quick update for those that haven't been following my blog (www.willegal.net/blog). The reproduction SCELBI PCBs are in and are in process of being assembled and tested. Front panel board appears to be working and I have clocks on the CPU card. The backplane is fitted to the chassis and ready to accept cards, though the front panel switches are not connected. There is quite a ways to go, but so far, so good, with no major issues with cards.

Finding, assembling and testing all the different cards and components are really making this project interesting. So far, I'm having more fun with this computer, than I did with the Apple II rev 0 and Apple 1 projects!

mwillegal
February 10th, 2013, 02:32 PM
See my reproduction SCELBI power up for the first time!

http://www.willegal.net/podcast2-2-13.mp4

mwillegal
March 3rd, 2013, 08:19 AM
I finished checkout of my reproduction SCELBI 8H board set and I have board sets available for sale. Checkout my blog at http://www.willegal.net/blog and my scelbi/8008 page at http://www.willegal.net/scelbi/the8008andScelbi.html