Micro Instrumentation and Telemetry Systems

Micro Instrumentation and Telemetry Systems, Inc. (MITS)

Company type	Private
Industry	Electronics, Computer hardware
Founded	December 1, 1969 (1969-12-01) in Albuquerque, New Mexico, United States
Founder	Ed Roberts, Forrest Mims
Defunct	1977
Fate	Acquired by Pertec Computer
Headquarters	Albuquerque , United States
Area served	United States
Key people	Ed Roberts (Founder)
Products	Electronic calculators, Altair 8800 microcomputer
Number of employees	110 (1973)

Micro Instrumentation and Telemetry Systems, Inc. (MITS) was a U.S.-based electronics firm established in Albuquerque, New Mexico, that originally manufactured electronic calculators beginning in 1971 and subsequently ventured into personal computers by 1975.

The company was founded in December 1969 by Ed Roberts and Forrest Mims, initially focusing on compact telemetry units designed for model rockets. In 1971, Roberts redirected the company's efforts toward electronic calculators, introducing the MITS 816 desktop calculator kit, which appeared on the November 1971 cover of Popular Electronics. These calculators achieved notable commercial success, generating sales surpassing one million dollars by 1973. Nevertheless, fierce pricing competition resulted in significant financial difficulties by 1974.

Roberts then created the first widely successful microcomputer, the Altair 8800, which was featured on the January 1975 cover of Popular Electronics. Priced at $397 as a kit, it garnered strong interest from hobbyists and attracted the attention of Paul Allen and Bill Gates, who started developing software for it—later named Altair BASIC. They moved to Albuquerque to join MITS and established Microsoft in July 1975.

By 1977, MITS had reached annual revenues of $6 million before being purchased by Pertec Computer. The brand was quickly integrated into Pertec’s operations and eventually phased out. After the acquisition, Roberts retired to Georgia to embark on a medical career.

Founders

Henry Edward Roberts pursued Electrical Engineering studies at the University of Miami before joining the U.S. Air Force in 1962. He served as an electronics instructor at the Cryptographic Equipment Maintenance School located at Lackland Air Force Base in San Antonio, Texas. To supplement his earnings, Roberts started Reliance Engineering and created electronics for commercial display applications. In 1965, he was selected for an Air Force program to complete his degree, earning an Electrical Engineering degree from Oklahoma State University in 1968 prior to his assignment at the Weapons Laboratory at Kirtland AFB in Albuquerque, New Mexico.

Forrest Mims demonstrated a passion for science and electronics early on, having built an analog computer during high school. He graduated from Texas A&M University in 1966 with a major in government and minors in English and history, then served as a U.S. Air Force intelligence officer. While stationed in Vietnam, Mims engaged in model rocketry and developed an infrared obstacle detector tested at the Saigon School for Blind Boys and Girls. His efforts attracted attention from military media outlets, which led to his assignment at Kirtland AFB's Weapons Laboratory despite not holding an engineering degree.

In 1968, both Roberts and Mims were assigned to the Lab’s Laser Group. Roberts revived Reliance Engineering, manufacturing an infrared intrusion alarm and collaborating with Stan Cagle on power supply projects. Meanwhile, Mims served as an advisor to the Albuquerque Model Rocket Club and established a connection with George J. Flynn, publisher of Model Rocketry magazine. This relationship resulted in Mims contributing an article about a transistorized tracking light for rockets launched at night in 1969. He became a frequent contributor to the publication, enhancing his reputation as both an innovator and business figure.

Model Rocket Kits

The surge of interest in model rocketry during the 1960s space race motivated Roberts, Mims, Cagle, and Air Force officer Bob Zaller to create and market electronic kits tailored for hobby enthusiasts. Initially contemplating the name Reliance Engineering, they ultimately chose Micro Instrumentation and Telemetry Systems (MITS), a title that captured their emphasis on miniaturized telemetry electronics. The December 1969 edition of Model Rocketry introduced MITS as a newcomer specializing in compact electronic telemetry systems designed for model rockets.

Their initial offerings featured the pioneering commercially available model rocket telemetry transmitter alongside various accessory modules, including tone beacons, temperature sensors, roll rate detectors, tracking lights, and lightweight batteries activated by water. Although these components were handcrafted in home workshops, sales were modest, reaching only several hundred units.

In May 1970, Mims authored an article on light-emitting diodes published in Popular Electronics, which boasted a circulation of 400,000. To tap into this broader audience, Roberts and Mims developed the Opticom—a device capable of transmitting voice through a beam of light. Both articles appeared on the November 1970 cover and earned them $400 collectively but more importantly connected them with Les Solomon, technical editor of Popular Electronics, who became instrumental in their business expansion.

Solomon visited Mims and Roberts in August 1970 and shared valuable knowledge about the kit industry from prolific authors such as Dan Meyer and Don Lancaster, who had established million-dollar enterprises selling kits. Although the exact sales per article were unclear, this encounter significantly influenced MITS’s strategic planning.

MITS manufactured 200 Opticom kits but managed to sell only about half. With some partners departing—Zaller had already left and Mims shifted focus to writing—Roberts purchased their shares for $600 in cash plus $350 worth of equipment, concentrating his efforts on designing an electronic calculator kit. Roberts concluded his Air Force service by mid-1972. Despite these changes, Roberts and Mims continued collaborating on publications and instructional materials.

Calculators

Ed Roberts’ fascination with computing began during his high school years and intensified while attending Oklahoma State University, where he had access to an IBM 1620 computer. By 1968, his office at the Weapons Laboratory was equipped with a Hewlett-Packard 9100A programmable calculator. In July 1970, semiconductor firm Electronic Arrays launched six large-scale integration (LSI) integrated circuits capable of supporting a four-function calculator. Roberts set out to design a calculator kit using these components.

To finance this project, Roberts sold a 15% stake in MITS to Air Force Lieutenant William Yates and secured additional funding from Major Ed Laughlin. Other officers from the lab contributed to the design process, while Forrest Mims authored the assembly instructions in return for receiving a kit.

The resulting MITS 816 was a four-function calculator performing addition, subtraction, multiplication, and division with an eight-digit display but offering calculation precision up to sixteen digits. Priced at $179 as a kit and $275 assembled, its professionally molded case enhanced its market appeal. Featured on the November 1971 cover of Popular Electronics, it generated thousands of orders monthly—far surpassing previous MITS kit sales.

Robust demand allowed for full-page advertisements in prominent magazines such as Radio-Electronics, Popular Electronics, and Scientific American. In June 1972, MITS introduced the Model 1440: a calculator with a fourteen-digit display featuring memory storage and square root capabilities priced at $199.95 (kit) and $249.95 (assembled). The original 816 kit’s price was reduced to $149.95. Both models were designed to interface with an upcoming programming unit.

By March 1973, monthly revenue reached $100,000, prompting relocation to a larger facility spanning 10,000 square feet. To keep up with assembled unit demand, MITS implemented automated wave soldering technology. At this stage, all calculators produced were sold promptly; employee count expanded to 110 workers operating two shifts.

With rapid advancements in calculator integrated circuits, Roberts developed new offerings. The MITS 7400 scientific calculator launched in December 1972 included trigonometric functions, polar-to-rectangular coordinate conversion, dual memory registers, and up to a seven-level stack. Kits featuring a three-level stack sold for $299.95; fully assembled seven-level stack versions were priced at $419.95. The next month saw the release of Series 1200 four-function pocket calculators priced at $59.95 for six-digit models and $99.95 for twelve-digit versions.

In March 1974, the Programmer accessory was introduced. Resembling a desktop calculator in size, it accommodated up to 256 programming steps expandable to 512 but was limited to emulating key presses and simple branching using hexadecimal commands. Although less sophisticated than Hewlett-Packard’s HP 9830 series, the combined cost of $400 for the MITS 7440 calculator plus programmer kits offered an affordable programmable calculator option for consumers.

MITS Calculator Models

Model	Features	Release Date	Kit Price	Fully Assembled Price
816	Desktop unit with 8-digit display, capable of 16-digit calculations, supports four basic functions	November 1971	$179	$275
1440	Desktop calculator featuring a 14-digit display, square root function, and memory capability	June 1972	$199.95	$249.95
816B	Desktop model with an 8-digit display, 16-digit calculation precision, and four-function operation	June 1972	$149.95	$189.95
7400	Desktop scientific calculator with a 14-digit display, trigonometric functions, and a multi-level stack ranging from three to seven levels	December 1972	$339.95	$419.95
1206	Portable handheld device with a 6-digit display and 12-digit calculation capacity, supporting four functions	January 1973	$49.95	$59.95
1209	Handheld calculator offering a 9-digit display and 12-digit calculation with four-function support	January 1973	$69.95	$79.95
1212	Handheld unit featuring a 12-digit display and basic four-function operations	January 1973	$89.95	$99.95
1230	Handheld device with a 12-digit display supporting four functions	January 1973	$89.95	$99.95
1240	Handheld calculator including memory and a 12-digit display with four-function capabilities	January 1973	$119.95	$149.95
7440	Desktop scientific calculator with a 14-digit display	March 1973	$199.95	$299.95
Programmer	A programming module supporting up to 256 steps compatible with the 7440 and other models	March 1973	$199.95	$299.95
150	Handheld calculator with an 8-digit display, including square root and memory functions	August 1973	$119.95	$149.95
941M	Handheld model equipped with percent calculations and metric conversion features	January 1974	$129.95	$149.95
908M	Handheld device offering square root and memory functionalities	January 1974	$99.95	$129.95
605M	Basic handheld percent calculator	January 1974	$49.95	$59.95
905M	Handheld calculator featuring percent function	January 1974	$59.95	$69.95
908DM	Desktop basic percent calculator	February 1974	$129.95	$149.95

Competitive Pricing Battles

The initial phase of the calculator industry was marked by fierce rivalry following Bowmar Instrument Corporation's release of the "Bowmar Brain," a compact four-function calculator retailing at $179 in September of 1971, which achieved sales exceeding half a million units during its first year on the market. Subsequently, Bowmar introduced the more affordable "901B," priced at $120.

In September of the following year, Texas Instruments (TI) made its entry into the sector with the TI-2500, a portable four-function calculator priced below $120 that incorporated TI's innovative TMS0100 "calculator-on-a-chip." This development established TI as both a chip supplier and direct competitor to other manufacturers dependent on their integrated circuits.

The marketplace rapidly attracted additional semiconductor firms such as National Semiconductor and Rockwell, alongside office equipment companies like Commodore Business Machines, resulting in aggressive price undercutting by early 1974.

Ed Roberts of MITS experienced shrinking profit margins as retail prices fell beneath production expenses due to larger competitors' capacity to sell at losses to capture market share; Bowmar eventually incurred losses amounting to $20 million and declared bankruptcy in early 1975.

Commodore acquired MOS Technology—their integrated circuit supplier—while TI's calculator division posted a loss of approximately $16 million in fiscal year 1975 despite prevailing in the pricing competition.

To maintain business viability amid these pressures, Roberts took MITS public in November of 1973 by offering up to half a million shares at one dollar each; however, only half of these shares were sold due to the stock market downturn triggered by the oil crisis that year.

The funds raised enabled MITS to clear outstanding debts but constrained opportunities for expansion; consequently, Roberts redirected marketing efforts toward test equipment and digital clocks aimed at kit enthusiasts rather than calculators.

By mid-1974, financial challenges resulted in reduced advertising activities alongside accumulated debts nearing $300,000.

In pursuit of a new competitive edge and strategic shift, Roberts resolved to create an affordable personal computer kit priced under $400 designed for hobbyists willing to engage in partial assembly.

After dismissing earlier microprocessors such as the Intel 4004 and Intel 8008 as either insufficient or overly complex for this application, Roberts selected the Intel 8080 chip despite its higher cost—approximately $75 each for an initial batch of one thousand units.

With a streamlined team numbering around twenty employees and backed by a bank loan of $60,000 to finance design and production phases, Roberts along with chief engineer Bill Yates initiated development of what would become a cornerstone product for MITS’s global footprint and recognition as an innovator in personal computing startups.

Popular Electronics and Radio-Electronics

In January 1972, Popular Electronics altered its editorial direction to appeal more to advertisers, emphasizing reviews of stereo gear and citizens band radios while discontinuing experimental project features. Prominent writers such as Dan Meyer, Don Lancaster, Forrest Mims, and John Simonton transitioned to rival publication Radio-Electronics. The June 1972 edition featured articles like Forrest Mims' "Experimenting with a $32 Solid State Laser" and Les Solomon's "Experiments with Op-Amps"; Solomon served as technical editor for both magazines. Lou Garner, a veteran solid-state editor, briefly moved to Radio-Electronics. Multiple MITS kit projects were published in Radio-Electronics, including the ITC 1800 Integrated Circuit Tester (May 1972), Model 1700 Function Generator (July 1973), Model 1440 Calculator (July 1973), and the 88 VLCT Computer Terminal (November 1974).

Although its readership was smaller, from 1972 through 1975, Radio-Electronics led the way in innovation by publishing numerous construction projects. John Simonton's modular electronic music synthesizer, featured on the May 1973 cover, launched the enduring PAiA Electronics product line. Don Lancaster’s TV Typewriter (September 1973) and Jon Titus’s Mark-8 computer (July 1974) played significant roles in advancing the home computer movement.

In 1974, Art Salsberg took over as editor of Popular Electronics, aiming to reclaim market leadership through superior computer-related content. Aware that MITS was developing a computer based on the Intel 8080 processor, he sought to showcase it in the January issue. Ed Roberts and Bill Yates completed the initial prototype in October 1974; however, a strike delayed shipments. Despite this setback, the article was published using photographs depicting a prototype equipped with switches and LEDs. The commercial Altair computer ultimately featured a circuit design different from that shown in the magazine.

Products

The Altair 8800 drew inspiration from early-1970s minicomputers such as the Data General Nova, comprising a CPU board along with memory and I/O boards; storage devices and display terminals were external peripherals. Commonly used terminals included the Teletype Model 33 ASR, which provided printed output and utilized punched paper tape for storage, as well as more advanced video terminals paired with 8-inch floppy disks like the ADM-3A. These systems lacked graphical capabilities, and lowercase characters were an optional $75 upgrade. Data input and system diagnostics were managed via toggle switches and indicator lights on the front panel.

The Altair 8800 kit came with a front panel, an Intel 8080 CPU board, 256 bytes of RAM, a four-slot backplane, and an 8-amp power supply priced at $439. Memory expansion boards ranged from $176 for one kilobyte to $264 for four kilobytes. Interface boards cost about $120 each. The Teletype Model 33 ASR terminal was offered at $1,500. A special bundle priced at $995 combined an eight-kilobyte system with Altair BASIC, Microsoft’s inaugural product developed by Bill Gates, Paul Allen, and Monte Davidoff. Released between July and December 1975 in several versions, Altair BASIC was discounted when purchased alongside memory and I/O boards to encourage sales.

After the January 1975 Popular Electronics issue featured the Altair, MITS faced overwhelming demand: over 1,000 orders arrived by February and more than 5,000 units were shipped by August. While the Altair itself was sold at cost, profitability depended on sales of additional memory and interface boards; by April 1975, more than fifteen optional boards were listed. However, many of these options suffered production delays until late that year.

Initially, MITS employed dynamic RAM (DRAM) for memory to reduce power consumption but encountered high failure rates due to design complexities. Competitors such as Processor Technology introduced dependable static RAM (SRAM) boards by mid-1975. In response, MITS launched its own four-kilobyte SRAM board in January 1976.

For data storage solutions, MITS selected the Pertec FD400 IBM-compatible eight-inch floppy disk drive offering over 300 kilobytes of capacity. The disk controller required two circuit boards containing more than sixty integrated circuits; its release was postponed from August until late 1975. The production version of Extended Disk BASIC was introduced in April 1976. Pricing for the disk controller with one drive was $1,480 as a kit or $1,980 assembled.

Marketing

MITS placed its initial full-page advertisements for the Altair in the February issues of both Popular Electronics and Radio-Electronics. Soon after, advertising expanded into specialized technical journals like IEEE's Computer magazine as well as general-interest publications such as Scientific American. MITS became a prominent advertiser within emerging hobbyist computer magazines including Creative Computing and Byte.

David Bunnell joined MITS as a technical writer during its calculator era. In April 1975 he launched Computer Notes, a newsletter designed to enhance communication with customers. Initially ranging from eight to twenty-four pages per issue, it shifted to a smaller magazine format in January 1977 before ceasing publication by January 1978. Bunnell later founded Personal Computer magazine in October 1976, advancing his career in publishing.

Contributors to Computer Notes included Bill Gates and Paul Allen who wrote about Altair BASIC and software topics. Ed Roberts penned a monthly "Letter from the President," addressing customer questions and reviewing competing products. Engineers such as Tom Durston and Steve Pollini provided technical articles on new offerings while Altair users contributed software code samples, hardware tips, and articles.

In April 1975, MITS acquired a camper van dubbed the "MITS-MOBILE," outfitted it with an Altair system along with floppy disk drives and a Teletype Model 33 terminal plus accessories. This mobile showroom toured various cities conducting seminars that attracted crowds exceeding two hundred attendees per event. A notable moment occurred in June 1975 at Rickey's Hyatt House in Palo Alto when a Homebrew Computer Club member obtained an unreleased copy of Altair BASIC. After retail computer stores became widespread nationwide, the MITS-MOBILE was retired.

The inaugural—and only—World Altair Computer Convention convened in Albuquerque in March 1976. Organized by Bunnell, it drew approximately seven hundred participants from forty-six U.S. states and seven countries; many attendees later became influential figures within the personal computing industry.

Clones

Delays by MITS in delivering the Altair 8800 spurred third-party manufacturers of compatible systems by mid-1975; fully assembled clones became widely available by July 1976. The Altair’s technical manuals included detailed electrical schematics of its proprietary hundred-pin bus connector which allowed others to design compatible expansion boards despite no formal standardization—resulting initially in inconsistent compatibility until adoption of the S-100 bus standard.

Bill Godbout Electronics based in Oakland supplied components to hobbyists and students from Berkeley. George Morrow partnered with Godbout to develop several Altair-compatible designs for sale. By October 1975 Godbout advertised a four-kilobyte RAM board priced at $131.07 compatible with Altair systems.

Godbout also provided parts to Processor Technology, which introduced a popular $160 video board compatible with the Altair designed by Lee Felsenstein. This card displayed sixteen lines of sixty-four characters on black-and-white televisions—a breakthrough that led Processor Technology to release their Sol-20 computer in 1976.

The IMSAI 8080, launched December 1975, was recognized as the first true Altair clone featuring improvements such as a larger power supply unit, twenty-two slot motherboard backplane, and simplified front panel wiring harnesses. Ed Roberts acknowledged these enhancements in his April 1976 Computer Notes column but noted that MITS’s upgraded Altair model 8800B surpassed IMSAI’s capabilities.

While official Altair systems were distributed exclusively through approximately twenty authorized dealers nationwide, clones like IMSAI’s model and Processor Technology’s Sol found wider distribution through hundreds of emerging computer retailers.

The S-100 bus architecture dominated personal computing expansions throughout the late seventies into the eighties until superseded by IBM PC's ISA bus standard. Seattle Computer Products (SCP) manufactured S-100 memory boards and developed an Intel 8086 CPU-based system prototype in 1979 used by Microsoft to test their Intel BASIC interpreter. When Digital Research failed to deliver an Intel-compatible CP/M operating system version on time, SCP engineer Tim Paterson created QDOS, an operating system developed within three months. Microsoft subsequently purchased QDOS for $50,000 adapting it into what became known as IBM PC DOS.

Altair BASIC

In December of 1974 Harvard student Bill Gates along with Paul Allen—then employed at Honeywell—noticed the Altair featured in Popular Electronics and realized it could run a BASIC interpreter program. Utilizing software tools created during their earlier Traf-O-Data project Allen built an emulator on a DEC PDP-10 mainframe allowing development before hardware availability; Gates manually coded assembly language routines for the Intel 8080 processor while fellow Harvard student Monte Davidoff contributed mathematical subroutines.

By early 1975 an initial version of BASIC was functional. After negotiating with MITS management Paul Allen traveled to Albuquerque in March to finalize arrangements for software delivery. The April issue of MITS's newsletter Computer Notes announced "Altair BASIC - Up and Running," with shipments commencing June 23rd priced at $500 but discounted to $75 when purchased alongside an Altair computer.

On July 22nd, 1975 MITS signed an exclusive ten-year worldwide license agreement for Altair BASIC paying Gates and Allen $3,000 upfront plus royalties capped at $180,000 total compensation. Allen assumed role as Vice President and Director of Software at MITS earning $30,000 annually; Gates remained a contractor while completing his studies at Harvard.

Despite this arrangement only about ten percent of early customers purchased official BASIC copies; many resorted to unauthorized versions due to high prices combined with unreliable memory expansions causing frustration among users resulting in lost royalties for developers. In response Gates published an "Open Letter to Hobbyists" in February of 1976 condemning software piracy.

In November of that year MITS announced development of the Altair 680 based on Motorola’s new MC6800 microprocessor but shipment was delayed until May of next year due to hardware complications. Allen rewrote their PDP-10 simulator for this new CPU while high school friend Ric Weiland ported BASIC into MC6800 assembly language code. To avoid royalty disputes this version was licensed non-exclusively for a flat fee of $31,200 paid by MITS.

Weiland together with Marc McDonald adapted this interpreter further for use on MOS Technology’s popular 6502 processor resulting in versions sold commercially through Commodore and Apple computers.

By January of 1976 Microsoft began marketing OEM licenses for their Intel-based BASIC directly through MITS distribution channels. After Pertec acquired MITS in December that year they halted OEM licensing efforts leading to arbitration proceedings concluded September 1977 favoring Microsoft: MITS retained limited non-exclusive usage rights but lost exclusivity allowing Microsoft freedom to license independently retaining all royalty income.

With no strategic reason remaining to operate from Albuquerque Microsoft relocated headquarters to Bellevue Washington in January of 1979 facilitating business expansion and talent acquisition.

Sale to Pertec

By mid-1976 MITS had grown its workforce to approximately two hundred thirty employees generating six million dollars annually in sales revenue. Founder Ed Roberts sought relief from daily management responsibilities pursuing strategic partnership opportunities instead. Having long utilized Pertec Computer Corporation disk drives within its products on December third that year Pertec signed a letter of intent agreeing to acquire MITS for six million dollars paid entirely in stock shares.

The acquisition closed in May of nineteen seventy-seven shortly before the National Computer Conference held that year in Dallas Texas where Pertec sought greater exposure for combined offerings. Roberts personally received two million dollars from this deal while remaining shareholders—including William Yates who co-designed the original Altair—divided remaining proceeds.

Pertec’s strategy shifted focus toward increasing sales among small business customers through twenty-six dedicated Altair Computer retail outlets across North America moving away from hobbyist markets altogether. The November nineteen seventy-seven edition marked final publication of Computer Notes produced by Albuquerque staff; one last issue followed under Pertec’s Chatsworth California office management before discontinuation altogether.

Altair advertisements ceased appearing within key industry publication Byte magazine after September nineteen seventy-seven issues reflecting declining marketing emphasis under new ownership while Roberts alongside Yates remained briefly engaged supporting special projects during transition period.

In August nineteen seventy-nine Pertec agreed sale of forty-five percent ownership stake valued at thirty-seven million dollars to North American Philips but soon thereafter itself was acquired by German conglomerate Triumph-Adler for one hundred twenty million dollars valuation.

By nineteen seventy-eight Pertec reported annual revenues reaching one hundred fifty million dollars while Triumph-Adler reported four hundred sixty-six million dollars respectively integrating former product lines including those originally developed under MITS brand name into broader portfolio offerings.

Manufacturing operations continued producing PCC-2000 small business computers at Albuquerque facility until closure occurred December nineteen eighty when production shifted permanently to Irvine California location.

Ed Roberts exited company operations by late nineteen seventy-seven returning homeward to Georgia pursuing medical career goals ultimately earning medical degree from Mercer University class of nineteen eighty-six practicing medicine locally until passing away in two thousand ten

Additional reading

A selection of magazine features from the 1970s that capture the era's excitement for technological progress and innovation:

External resources

• STARTUP: Albuquerque and the Personal Computer Revolution at New Mexico Museum of Natural History and Science
• MITS Model 7440 Desktop Scientific Calculator on Old Calculator Web Museum
• MITS 150 Handheld Calculator featured at Vintage Calculators Web Museum
• TI-2500 showcased at Datamath Calculator Museum
• Altair 8800 Computer displayed on Vintage-Computer Web Site
• Forrest Mims – Early Experiences at MITS (archived)
• Concise Altair History with reprints from Popular Electronics