Hello friend! Before we had slick laptops and mobile phones, there was an era when computers were solely found in research labs and large militaristic halls occupied by flashing lights and tape drives. But in the 1970s, daring engineers and entrepreneurs believed that ordinary people could understand – and even own – such devices to improve life and work.
The Sol-20 was one pioneering machine built with this vision. So join me in a fun retrospective on the roaring rise and fade of this trailblazer that paved the way for computing‘s personal side!
Conception at a California Startup
In November 1975, an excited conversation occurred that would alter the course of computing history. Electronics engineer Bob Marsh had started Processor Technology months earlier in Berkeley, California to supply component boards for the hype-generating Altair 8800 computer kit.
He met with Les Solomon, technical editor for Popular Electronics – the magazine that had introduced the Altair to the world. Les wanted a construction article for a computer terminal with the latest microprocessor innards that hobbyists could assemble themselves. This would be a big win to sell more magazine copies.
But here was the catch – Les needed a working prototype delivered within 30 days if Processor Technology wanted the cover spot to promote their business!
Marsh recruited a hardware designer named Lee Felsenstein who had tinkered with Processor Technology‘s video board for the Altair earlier. Felsenstein was known for his unconventional thinking and get-things-done attitude. Together with manager Gordon French, they hunkered into long days of furious work into January 1976 to piece together a prototype terminal for Popular Electronics.
But ambitions ran high, and features kept being added until their device could run programs on its own! Marsh realized they had inadvertently created one of the world‘s first complete personal computers. Though uncertain this would excite Les, they packaged the machine and Felsenstein lugged it to demonstrate in New York.
Initial disaster struck – jostled hardware caused it to not boot at the magazine‘s office! "My heart sank into my stomach as nothing at all happened when we turned it on," Felsenstein later recalled. But after hours of troubleshooting damaged wires, the scrappy device finally lit up to both men‘s relief. Impressed by the capabilities and steep discount to buy 5000 kits, Popular Electronics agreed for a cover story. Little did they know how wildly popular this device would become!
Launching a Blockbuster Hit
In July 1976, Popular Electronics formally unveiled the Sol-20 as a $995 kit computer for hobbyists to assemble on its magazine cover. For those wanting a pre-built system, Processor Technology announced a commercial Sol-20 model priced at $2129.
This made the Sol one of the earliest fully integrated, ready-to-use personal computer packages brought to market. Marsh, Felsenstein and French were betting ordinary folks would pay over $2000 to own this miniature wonder machine for their homes and offices!
And bet they did right – over 10,000 units were eventually sold between 1976-1979! The Sol-20 became a blockbuster success as the world‘s highest selling personal computer by 1977. Let‘s analyze what made this pioneering machine so enormously popular in its heyday:
Friendly Interface – The Sol sported a full QWERTY keyboard for quick text input instead of tedious switches. It output color video to CRT monitors and televisions familiar to most mass market consumers at the time – not just obscure hexadecimal codes for hobbyists!
Reliability – Two built-in cassette drives for data storage and an integrated power supply made the Sol far more turnkey than finnicky Altair kits owners had to wire themselves. It fired up with remarkable quickness to start programming within seconds.
High Performance – Packed with a 2 MHz 8080 CPU, 64KB RAM and 7 S-100 expansion slots, the Sol was no slouch! Business users found its number-crunching power comparable to $20,000 minicomputers of the era! Games and graphics ran faster than competitors.
Low Cost – Priced at just over $2000, the Sol made incredible capabilities affordable to the middle class compared toscientific equipment and time-share mainframes worth hundreds of thousands of dollars. Schools and universities snapped units excitedly.
Behind the scenes, Processor Technology was overwhelmed by roaring customer demand as both novice and experienced enthusiasts clamored for the acclaimed Sol-20 system!
By expertly balancing innovation and pragmatism for both hobbyists and business audiences, the Sol-20 became 1977‘s best-selling personal computer and Lee Felsenstein a celebrity in early computing circles. But the ride was just getting started!
Engineering Feats Behind a Iconic Design
Befitting its trailblazing guts, the Sol-20‘s sleek appearance hid an unconventionally frugal yet clever arrangement within. Cost and size constraints led Lee Felsenstein to creatively mount boards horizontally rather than typical vertical slots.
Center-cut walnut timber pieces from Marsh‘s acquaintance constrained height while keeping machining costs low. This resultant compact, low-profile desktop form factor made Sol an iconic symbol of personal computing compared to hulking scientific gear of the past.
But Sol‘s uniquelaytout was not just visual charm – it pioneered now ubiquitous engineering concepts:
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Horizontal Board Mounting -industry practice was vertically install cards for airflow as sideways placement seemed to increase failures. But Sol disproved assumptions and made horizontal orientation viable through rigorous testing.
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Distributed Processing – Sol dedicated an auxiliary board solely for video terminal emulation instead ofassigning this intensive task to the main CPU. This novel separation of concerns became foundational for specialized co-processors.
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Integrated Text-Based UI – Sol‘s inclusion of the Processor Tech character generator for display output and full ASCII keyboard for input established text interaction as the primary computer interface still standard in operating systems today.
So along with being a commercial smash hit, the Sol-20 made seminal hardware contributions that shaped personal computing for decades!
Felsenstein and Marsh testify to burning hundreds of operational hours across months proving Sol‘s durability. "If we could get 500 hours out of a board, we were feeling pretty good," Marsh chuckled. "I remember leaving a whole bunch of Sol systems turned on just running programs overnight to validate them". Such rigorous efforts cemented Sol‘s reputation for resilience and reliability among customers.
Legacy as an Early Computing Pioneer
While the Sol-20 had a short 1979-79 lifespan before Apple II and Tandy TRS models took over, it strongly impacted early computing evolution:
Established Market Viability – Sol‘s record sales demonstrated clear mainstream demand for personal computers beyond niche hobbyist circles. It paved the way for subsequent entrants eyeing this lucrative new market.
Inspired Peer Innovators – Legends like Steve Jobs, Steve Wozniak and even Bill Gates purchased Sol kits admiring Lee Felsenstein‘s work. It influenced many pioneers who left their own giant marks on the industry.
Ushered Commoditization – As a very early mass-produced PC selling over 10,000 units, the Sol helped drive down computing costs from room-sized mainframes to affordable appliances for personal use. This commoditization transformed digital technology into a participative pop culturephenomenon rather than an elite privilege!
So while it had fleeting fame, the Sol‘s immense impact hopefully continues to inspire computer engineers today to keep finding ingenious ways to make technology more open and empowering for people, just like those Processor Technology founders did back in 1976!
Even four decades later, the Sol‘s iconic smart industrial design, engineering firsts and meteoric market success shine as symbols of enduring innovation from California‘s fertile Silicon Valley region – birthplace of the computing dreams that now power our world!
I recently caught up with Milton – a Bay Area tech consultant and hobbyist who revamped his childhood Sol-20 kit a few years ago to celebrate its 40th birthday. He excitedly described getting "addicted for 3 months" writing tiny Basic programs to make lights blink and type text passages.
Though still a teenager, Milton recognized the Sol‘s friendly interface opened up coding creativity for him beyond other machines requiring special terminals or operating procedures. "It was place I could just stick a TV and start playing," he fondly recalled. The Sol-20‘s enduring legacy lives on inspiring new generations of tinkerers!