Radio frequency interference




After the first wave of game consoles and computers landed in American homes, the United States Federal Communications Commission (FCC) began receiving complaints of electromagnetic interference to television reception. By 1979 the FCC demanded that home computer makers submit samples for radio frequency interference testing. It was found that "first generation" home computers emitted too much radio frequency noise for household use. The Atari 400 and 800 were designed with heavy RF shielding to meet the new requirements. Between 1980 and 1982 regulations governing RF emittance from home computers were phased in. Some companies appealed to the FCC to waive the requirements for home computers, while others (with compliant designs) objected to the waiver. Eventually techniques to suppress interference became standardized.

Comments

Post a Comment

Popular posts from this blog

Notable home computers

Image
The time line below describes many of the most popular or significant home computers of the late 1970s and of the 1980s. The most popular home computers in the USA up to 1985 were: the TRS-80 (1977), various models of the Apple II family (first introduced in 1977), the Atari 400/800 (1979) along with its follow up models the 800XL and 130XE, and the Commodore VIC-20 (1980) and the Commodore 64 (1982). The VIC was the first computer of any type to sell over one million units, and the 64 is still the highest-selling single model of personal computer ever, with over 17 million produced before production stopped in 1994 – a 12-year run with only minor changes. At one point in 1983 Commodore was selling as many 64s as the rest of the industry's computers combined. The British market was different, as relatively high prices and lower disposable incomes reduced the appeal of most American products. New Scientist stated in 1977 that "the price of an American kit in dollars rapidly tr
Read more

Background

Image
As early as 1965, some experimental projects, such as Jim Sutherland's ECHO IV, explored the possible utility of a computer in the home. In 1969, the Honeywell Kitchen Computer was marketed as a luxury gift item, and would have inaugurated the era of home computing, but none was sold. Computers became affordable for the general public in the 1970s due to the mass production of the microprocessor starting in 1971. Early microcomputers such as the Altair 8800 had front-mounted switches and diagnostic lights (nicknamed "blinkenlights") to control and indicate internal system status, and were often sold in kit form to hobbyists. These kits would contain an empty printed circuit board which the buyer would fill with the integrated circuits, other individual electronic components, wires and connectors, and then hand-solder all the connections. While two early home computers (Sinclair ZX80 and Acorn Atom) could be bought either in kit form or assembled, most home computers were
Read more

Home computer

Image
Home computers were a class of microcomputers that entered the market in 1977 and became common during the 1980s. They were marketed to consumers as affordable and accessible computers that, for the first time, were intended for the use of a single nontechnical user. These computers were a distinct market segment that typically cost much less than business, scientific or engineering-oriented computers of the time such as those running CP/M or the IBM PC, and were generally less powerful in terms of memory and expandability. However, a home computer often had better graphics and sound than contemporary business computers. Their most common uses were playing video games, but they were also regularly used for word processing, doing homework, and programming. Home computers were usually not electronic kits; home computers were sold already manufactured in stylish metal or plastic enclosures. There were, however, commercial kits like the Sinclair ZX80 which were both home and home-built co
Read more