Parasitic Engineering

Parasitic Engineering, Inc.

Company type	Private
Industry	Computer hardware
Founded	1974
Founder	Howard Fullmer, Gene Nardi
Defunct	1983
Headquarters	Oakland, California (initially), later Albany, California , United States
Products	Hardware upgrade kits for MITS Altair 8800, S-100 bus microcomputer (Equinox 100), upgrades for Tandy TRS-80 including Maxi-Disk floppy disk system and CP/M compatibility boards

Parasitic Engineering, Inc. was an American computer firm established in 1974 by Howard Fullmer and Gene Nardi in Oakland, California. Its name was a playful retort to MITS co-founder Ed Roberts’ disparaging label of third-party vendors as "parasite companies." Initially, Parasitic focused on manufacturing hardware upgrade kits for the MITS Altair 8800 microcomputer, enhancing its power supply and mitigating noise problems. Subsequently, the company launched its own S-100 bus microcomputer, which did not achieve the same level of success as their enhancement kits. By 1979, Parasitic redirected its efforts toward producing upgrades for Tandy's TRS-80 before ultimately shutting down in 1983.

Foundation (1976–1977)

Howard Fullmer and Gene Nardi, who had previously worked as computer consultants at the University of California, Berkeley, founded Parasitic Engineering in 1974. The enterprise began as a side project operating out of Fullmer’s basement in Oakland but transitioned into a full-time endeavor by 1976 due to a notable increase in revenue. By 1977, the company had grown to employ nine staff members and reported gross profits amounting to $250,000.

The choice of the company’s name was an intentional reference to Ed Roberts’ 1975 criticism targeting third-party hardware manufacturers such as Processor Technology, whose static RAM board competed directly against MITS’ dynamic RAM board bundled with Microsoft BASIC. Despite MITS’ efforts, their dynamic RAM board experienced technical difficulties and failed to gain significant market traction against Processor Technology’s product. Fullmer had initially considered naming the company Symbiotic Engineering but decided against it because of its association with the Symbionese Liberation Army.

Parasitic’s inaugural product was a clock controller board for the Altair 8800 introduced in 1976 to resolve oscillator instability caused by noise and temperature variations. In 1977, they released a power supply upgrade kit that replaced the Altair’s linear regulators with a constant-voltage transformer supported by high-quality capacitors and rectifiers. This modification enhanced both power capacity and reliability, particularly when used alongside Processor Technology’s energy-demanding static RAM board.

To broaden their international reach, Parasitic established distribution channels across Europe in 1977 with the goal of competing against emerging European and Japanese computer manufacturers. The company forecasted profits reaching $1 million for the year 1978.

Equinox 100 (1977–1979)

In June 1977, Fullmer collaborated with George Morrow, another supplier of Altair-compatible hardware, to create the Equinox 100—a microcomputer marketed by Parasitic Engineering based on the S-100 bus standard. This system incorporated an Intel 8080 processor, twenty S-100 expansion slots, 4 KB of RAM, an integrated hexadecimal keypad paired with a seven-segment LED display, RS-232 serial and parallel ports, as well as a cassette interface. The operating system named COPE (Cassette Operating Executive) was developed internally.

The Equinox 100 featured circuit boards designed by Morrow with Fullmer providing electrical engineering expertise. They reinforced the durability of the S-100 bus architecture drawing on advice from industry experts such as Bill Godbout and Bob Mullen of Diablo Data Systems. However, by the time the product launched, the Intel 8080 was becoming obsolete compared to more advanced processors like the Zilog Z80, which constrained sales performance. Nonetheless, their contributions played a role in shaping the formal S-100 bus specification standardized as IEEE 696 in 1982, with both Morrow and Fullmer credited as partial contributors.

Pivot and decline (1979–1983)

In 1979, Parasitic Engineering moved its main office to Albany, California and redirected its efforts toward producing aftermarket hardware enhancements for the TRS-80, which was distributed by Tandy Corporation through Radio Shack. One of their initial products was the Maxi-Disk—an 8-inch floppy disk system that combined a Shugart Associates drive with a custom expansion card developed by Parasitic. By 1982, the company broadened its offerings to include additional disk drive units, CP/M compatibility boards tailored for the TRS-80, and a "data separator" circuit board designed to boost read accuracy on high-density floppy disks.

The business ceased operations in 1983 following its suspension by the California Franchise Tax Board. Experts in the field commonly link Parasitic’s downfall to the emergence of the IBM Personal Computer after 1981, which transformed the microcomputer industry into a mass market and eroded the competitive edge held by companies targeting hobbyist consumers.