NOTE: This Sphere system has been purchased by the Early Computer Museum, a project of the students and faculty at West Chester University of Pennsylvania who are interested in conducting research into the history of personal computing.

    In 1975, a year before the Steves came on the scene and the Altair came to life, Sphere Corporation built "the first 'true' PC," according to Byte Magazine.  


    "The first true personal computer was created by Michael Wise in 1975, and was called the Sphere 1. Initially, Sphere 1 was sold as a kit, but later became available to consumers fully assembled. The Sphere 1 qualified as The First Personal Computer because it was designed for consumer use and included a keyboard, a number pad, and a monitor. After Wise's development, a mass amount of new types of computers were introduced throughout the next several years"  


    This prototype Sphere 1 vintage computer system is the only one of its kind, the first of a limited run of 1,300 units. You can view the Sphere 1 schematics here. 

     It appears to be what would have been marketted as a "System 330".  It includes these cards:

    •  CPU/1 which is the computer
    • SIM/1 which is a communication card that allows it to be attached to a modem, among other things
    • CRT/1A which is the video driver card.  This had an optional subcircuit allowing it to be hooked to a normal TV.  that hasn't been populated here.
    • MEM 1 which is the 16 K memory expansion board.

    All the boards are dated 1975 except the SIM/1 which has a screen print date of 1976 when the board revision was drawn, so this board that was either designed/revised later, and then possibly then added to the computer.  

     This doesn't include disk driver or printer driver boards which would have been included in the retail "System 340" setup.

     According to the manual, the 330 included a version of the Basic language in rom.  I'd imagine this should have that, but can't say for sure.

     In the Sphere 1 pictures on the right you can see a visible power supply on the internal chassis under the monitor.  That chassis has an old-style AC receptacle on it.  This is only the supply for the monitor.  The multipin connector on the back is for an external supply, not power, so in order to run it, you need both an external power supply for the computer and an old-style AC cord for the monitor.  I haven't attempted to power this up, as I don't have a power supply for it.

     The power supply voltages are the same as any standard modern computer, +/- 5V and +/- 12V, so any computer supply should be able to power it. You could either make a DB9 connector for the back panel, or just wire directly to the barrier strip inside the box. The latter would likely be best.  One of the cards has a hand drawn diagram of the power bus pinout, and I imagine the manual does as well. Theoretically one could still power up the computer using a standard supply. However, you would need to find an AC cord for the monitor.

    It is an extremely rare system, truly a valuable piece of PC history.  It may or may not be functional and is sold as-is. It is clean and all the inner workings can be clearly seen. This Sphere 1 vintage computer has been safely stored and kept in the possession of Mike Wise, the creator and founder of Sphere, until his death in 2002, since which time I (his daughter) have stored it. 

    See the original advertisement.


    The "inventor" of the personal computer has been unclear for decades and is difficult to pinpoint without a universal definition of a PC. Byte magazine named the Sphere I the first PC because it was the first mass-marketed computer that contained both the monitor and the keyboard within the body of the system.  

    • Before Sphere, Micral N was the earliest commercial, non-kit microcomputer based on a microprocessor, the Intel 8008. It was built starting in 1972 and about 90,000 units were sold. 
    • The first "personal computer," defined as such by Byte Magazine due to its consumer focus and built-in keyboard and monitor, was the Sphere 1 computer, created in Bountiful, Utah in 1975 by computer pioneer Michael D. Wise (1949-2002). At first, Sphere 1 was sold as a kit, but was later sold as fully assembled PC, including a keyboard, a number pad, and a monitor. 
    • In 1976, Steve Jobs and Steve Wozniak sold the Apple I computer circuit board, which was fully prepared and contained about 30 chips. 
    • The first successfully mass marketed personal computer was the Commodore PET introduced in January 1977, which bore a striking resemblance to Sphere 1 of two years earlier. It was soon followed by the TRS-80 from Radio Shack and the popular Apple II.

    Interestingly, many of the PC "Founding Fathers" knew each other, held conferences and  shared ideas with one another.  For better or worse, Michael Wise in particular was known for his talkative excitement about his ideas much more than his desire to protect them from potential competitors. In fact, he personally presented the Sphere specs to Radio Shack one year before the TRS-80 was released. But what he lacked in corporate savvy, he made up for in technical genius, some of which is still in use today.


    Sphere was founded by an inventor, not a businessman.  The company began advertising before the product was fully debugged in order to finance its growth. Enormous, unexpected demand overwhelmed the company, which was literally killed by success. Competitors quickly filled the void. Nonetheless, the Sphere had made its mark on the history of the PC, and contributed to both the specs and design of future generations of hardware.

     "I argue to this day that the Sphere was the first integrated PC.  Then came the SOL, THEN the Apple.  My attitude has offended Steve Jobs, who comes to a different conclusion."

    ~Gordon French, Homebrew Computer Club


    Byte Magazine Issue #2: October 1975: Visit to "Sphere Corporation"

    Byte Magazine Issue #11 July 1976: How to Assemble a Sphere Computer (TOC Only)

    Byte Magazine December 1976: Follow Up and End of Sphere

    Sphere Items on file at the Computer History Museum

    Vintage Computer Festival 3.1 Conference Bio

    A Systems Commentary

    Michael D. Wise Obituary