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This is my little attempt to document and share information about an interesting and, arguably, historic machine.

The Sol 20 microcomputer was a product of the Processor Technology Corporation, circa 1977. The Sol 20 is interesting in that it came at the dawn of the "microcomputer revolution." It is interesting in that it was the main product of Processor Technology, an archetypal rags to riches to rags startup company.

This site is mostly a collection of documents, software, and other artifacts; it isn't so much about the history of the computer or the company that made it. I was only 13 year old kid at the time the Sol was around, and had to be satisfied poring over the color ads in Popular Electronics. In 1999 I picked one up at a ham fest for $20, satisfying a latent wish. Precious little information about the Sol was on the internet back then, so I started this site.

Introduction (link)

The Sol-20 was produced by the Processor Technology Corporation back in 1977-1979. About 10,000 of them were produced, some as kits, some as pre-built.

Processor Technology had planned on three forms of the machine: the Sol-20, the Sol-10, and the Sol-PC (note that use of "PC" years before IBM-PC ever showed up). The Sol-10 was intended to be a stripped down Sol-20, functioning as a "smart terminal." The Sol-10 didn't have the expansion backplane, lacked the numeric keypad (optional), had a wimpy power supply and didn't require a cooling fan. The Sol-PC was intended to be a single-board computer, which was not uncommon in the day. It was basically the motherboard from the Sol-20. However, it appears that few if any configurations other than the Sol-20 were ever shipped.

Others have already done a much better job than I ever will at documenting the history of the Sol and the company, so instead I'll just focus on archiving listings, programs, documents, what have you. If you want to read an interesting account of the meteoric rise and fall of Processor Technology, get hold of a copy of the book, Stan Veit's History of the Personal Computer.

One more introductory note: for a long time I waffled over how to pronounce "Sol." Should it be pronounced with a long o, like "soul," or should it be pronounced with a short o, like "Saul?" In October of 1999, I had the pleasure of meeting Lee Felsenstein, the main designer of the Sol, and he said unequivocally it is pronounced like "Saul."

SOLicitations (link)

• Known holes in the archives:
  • Contents of Proteus software collections #4, #5, #6, #9, #10
  • Source code to Processor Tech software. Most of it was released when the company folded, so it must be out there somewhere.
• Do you have any relevant files you want to send my way? I'd be happy to host them here and give you a tip o' the hat.
• Do you have any paper documents you could share? Check out my Sol manuals page, and if I don't have it already, maybe it is something that I could scan and put online.
• Do you have any Sol program tapes? Perhaps you can send me a WAV file, or I can tell you how to dump the file in HEX so that you can send that to me. Or, barring that, maybe you could duplicate the tape, or mail it to me so I can clone it and mail it back to you.
• Do you have a Sol personality module ROM that I don't already have archived? Can you dump its contents so I can archive it?

If you answered "yes" to any of these questions, let me know!