Sunday, March 17, 2013

Vintage computer SCELBI 8B Microcomputer 1975

Updated 5/5/17
Some time ago I noticed a request in one of the Microcomputer Retro group postings " any SCELBI microcomputer collectors out there ?"   I remembered that years ago I received one for my historical collection & had not looked at the computer for 20 years or more.  This perked up my interest and I replied that I had one and would find it in the storage warehouse. This started some very interesting dialog for me as I knew about the SCELBI computers of the mid 70's but did not really know much  about the one in our collection.
                                                                                                          Click on photo's to enlarge
SCELBI computer
SCELBI in David's Collection

I was asked by the collector looking for others with a SCELBI - was mine a model H or B? Frankly I did not know which model  it was and took photos & sent to the collector.  A few emails back and forth I learned mine was a B (Business model) and that very few had been identified in existing collections.  Mike Willegal  heard that I had one and ask for some photos. WOW - he reported only three were known to be in collections and mine made the fourth.  Mike has a great blog and is very active in making exact reproductions of some of the rare and interesting microcomputers and you can see his work on his  blog  - He is making reproduction cards of the SCELBI at this time and has some operational.  Mike is a very serious historian and collector of microcomputers. One of his many projects is maintaining the "Apple 1 Registry" with only 46 units positively identified at this time.

            David give a little history about this SCELBI Microcomputer

SCELBI computer
Original Receipt for SCELBI cards
The current interest in the SCELBI microcomputers really gave me the incentive to look closely at mine.  The microcomputer looks to be in good condition and well built.  I obtained the computer from Robert S. Forman who was a skilled craftsmen when he built it - you can see this in some of the  photos on this post.

The SCELBI came with a lot of documentation in nice condition. The original receipt for the SCELBI cards purchased in 1975 is signed by Robert Findley co-founder with Nat Wadsworth of the SCELBI company.

Nat Wadsworth SCELBI start up in his words.    Nat has indicated that about 200 computers were made
by SCELBI 1/2 kit and 1/2 assembled  units & about 1/2 the total were 8B models.

SCELBI computer
Note with Carl Helmers original signature
SCELBI Computer
Included is a note with an original signature of Carl Helmers when he was publishing his ECS newletters dated February 15, 1975.  Carl Helmers went on to be the first editor of "Byte Magazine" September 1975.

Many manuals, other operating documents and copies of the only four SCELBI newsletters published also included.  Very interesting reading.

SCELBI computer
SCELBI Catalog
SCELBI computer

The first advertisement published by SCELBI was in the March 1974 issue of QST magazine.  I have a copy of the magazine to go with the documents.
SCELBI computer
Copies of the only 4 SCELBI newsletters

SCELBI computer
Custom Cassette Interface card

SCELBI computer
Side view SCELBI Computer
The side view shows some of the custom interface cards and bus connectors for them.

The larger card with the gold IC is a "Digital Group" TV Typewriter card. Mike Willegal reports this is the only one with built in video card.  The computer has the normal switch register input and a keyboard input. Robert Forman the builder of this unit put a lot of time and his passion into making this really nice computer. Some may think the wood frame case holding the computer is a strange way to mount the unit however for the early days of home built microcomputers this is a beauty.

                                            Additional post about the SCELBI Computer

This SCELBI computer along with the entire 30 tons of my "Bugbook Historical Microcomputer collection"  is now located in the "Computer Museum of America" in Roswell, Georgia ( moved March 2016). 

Gaynell my wife & I, Dee Wallace
 In my previous post I mentioned wearing many hats. Here I am with the full LCF Group - me & my wife Gaynell and our associate of many years Dee Wallace.  The group  manages our different activities and of course one of those is the "Bugbook Historical Microcomputer Museum" and collection.  We have also been active for over 40 years in farming and doing rural development. We were major Christmas tree growers for more than 25 years and continue work with helping others obtain their dream land here in the Blue Ridge Mountains.  Look here for some of these activities http// Chantilly Farm
David Larsen


  1. This has been fun looking at this SCELBI computer. I have enjoyed working with other the computers in my collection. Opening up some of the 8800 Altairs and seeing the cards folks used was interesting. Some are really loaded with lots of cards but not a lot of original Altair cards.

    The SCELBI 8B has been very interesting as I have studied some of the manuals and it brings back a lot of memories for me. I never really used a computer very much that used the 8008. I have several of John Titus's MARK 8's but we got into the 8080 very early on and that and the Z80 were used in my teaching at Virginia Tech for a number of years. I also see that SCELBI missed the boat by keeping the 8008 in the HB model as almost all folks jumped on the 8080 and left the 8008 in the dust. Their rational was that it was best because a lot of software was available for the 8008 already. That was only a very short term advantage and basically the 8B died a natural death as no one really wanted to used the 8008 anymore. As I mentioned it is fun looking again at this early stuff.
    David Larsen - Computer Collector/Historian

  2. Here is comment from Josh in reply to the above.

    Yes, there was many fortunes gained and lost due to poor vision of the future. Like the SCELBI , the MCM/70 was another computer based on the 8008 that did not migrate to the 8080 and suffered the consequences. A huge amount of time was spent writing 8008 code. It was done using slow and crude tools. By the time the 8080 hit the market, people were still just perfecting the 8008 code and wanted return on their investment. These early pioneers of the PC revolution suffered for being there first.

    Your students were very lucky to be taught by someone with your passion towards computers. I think you had the perfect job at the right time. Now kids in the schools are lazy and the material isn't as revolutionary as these wonderful classic computers.

    Do you know the story of the Osborne computers? It's a classic story of what NOT to do in business. Sales of their first computer was booming, to keep up with demand they sank a lot of money into bigger production. Right after spending this money on the first computer, they released their 2nd generation computer which killed the sales (and ROI) of the first computer.

    Things are warming up here, Spring has arrived. That should let you get more access to your warehouse and give me more chores to do around the house!


I look forward to your comments and will respond.