Articles by La Machine

Technology

RF Shielding History: When the FCC Cracked Down on Computers

When computers hit homes, the FCC’s RF interference concerns kicked into overdrive At first, computers largely appeared in businesses and universities. They hadn’t quite hit the home just yet, though electronics that had computing elements—think Pong consoles and the like—were starting to make their presence known. That meant that these devices, like every other type of electric device (even light bulbs), could be a new source of RF interference, and as the personal computer started to gain attention and popular uptake, the industry had to adapt. Stuff like the Altair’s accidental musicianship would not fly. And so too, did the Federal Communications Commission, which asked the public in 1978 to help determine a plan of action for better managing RF interference, after getting flooded with complaints for years on end. An inquiry document implied that the FCC was considering its options for about regulating this technology. The organization implied that it may not be cost-effective or even necessary, and even floated a voluntary approach. “Greater immunity will require more sophisticated design, additional components, and increased testing, all of which will increase equipment production cost. The magnitude of this increase will depend upon the immunity standards prescribed,” the commission wrote, adding that the public may still choose the cheaper, unshielded option if given the choice. After spending time digging in, however, it’s clear the agency decided that they needed to take a harder line than the voluntary one posed. After all, computers were taking over the household, and so too were VCRs, video games, walkie-talkies, and all matter of electronic devices. Of course, the computer industry was still very immature at this time, with devices like the Commodore PET, TRS-80, and Apple II still quite new, each representing early attempts at bringing personal computers to a large home market. We were a step beyond the pure hobbyist nerdery of the Altair but far from maturity. The FCC wanted to head off issues with these new devices before things went too far—and saw the dynamic around consumer devices as being distinctly different from commercial platforms. By September 1979, the FCC was ready to weigh in, and it was worried about your neighbor’s TV experience above all else. “We are most interested in protecting an individual who is receiving interference from his neighbor’s computer. To a lesser extent, we are concerned about devices in the same household,” the agency wrote in its rulemaking document, FCC 79-555. (The goal? To prevent interference so bad that it harmed the experience for someone in a completely different home.) The document, which applied Part 15 regulations to computers for the first time, made clear that CB radio played a decisive factor in the final result. (Especially given the timing, which came mere months after the FCC highlighted the sheer scale of complaints it received.) The commission learned a lot from its more laissez-faire approach, which ultimately damaged the consumer experience. “Unless the Commission acts expediously to head off the problem, we may be faced with an intolerable interference problem similar to CB interference problems of several years ago,” the commission continued. This was not good news for all these technology startups in the budding computer industry. Suddenly, companies large and small had to share their new products—and presumably, their trade secrets—with the FCC in an attempt to ensure that the electronics were safe to sell. This created major headaches, especially for companies that already had products on the market, which now had to stop producing RF interference on TV and radio frequencies altogether. As the magazine Kilobaud put it in 1981: “After three years of study, the FCC handed the microcomputer industry a mandate: Get rid of the RFI by January 1981, or close up shop.” These standards meant additional testing—including the use of a spectrum analyzer and a dedicated testing site to ensure that equipment meets respectable radiation standards. And these standards could be quite confusing for manufacturers, even affecting things like upgradeability. Per Kilobaud’s Chris Brown and Eric Maloney, “As far as the FCC is concerned, an 8K CPU that has the potential of being upgraded to 16K is actually two different computers.” Put simply, this put a huge testing onus on manufacturers, likely raising prices in the short term and leading to additional metal shielding as a band-aid to retrofit existing designs to fit the FCC’s regulations. Large manufacturers likely were already doing a lot of this on their own. The problem was that this put a lot of additional pressure on the makeshift startups that made the sector viable in the first place. Manufacturers had to adapt. For example, Apple released newer iterations of the Apple II, such as the Apple II Plus and Apple IIe, to help improve the electromagnetic noise that the original created. (Which means, if you want a computer with no RF shielding because you desire to make music via radio interference, get the original Apple II.) Apple had to take this stuff seriously, because the FCC was paying special attention to them. The company was specifically cited in the commission’s rulemaking as being aware of the problem as far back as 1976. And it got nailed at least once for noncompliance: On top of all the other challenges that the ill-fated Apple III faced, the machine had to be recalled and replaced with a new model because its RF shielding wasn’t good enough. Ironically, the rules were way less strict for computers in office or industrial environments, which received a Class A regulation, than for consumer tech, which required the stricter Class B designation. After all, if the goal is to prevent radio interference, your Facts of Life-watching neighbor is going to have bigger issues than your spreadsheet-embracing co-worker. All of this was a pain to manage, but you’ll be surprised to learn that, in the end, all this added regulation probably ended up making the computer industry better.