elektronika: ZX81

Evidence: 100 • authority: 72

The ZX81 is a home computer developed by Sinclair Research and manufactured in Dundee, Scotland, by Timex Corporation. It was launched in the United Kingdom in March 1981 as the successor to Sinclair's ZX80 and designed to be a low-cost introduction to home computing for the general public. It was hugely successful; more than 1.5 million units were sold. In the United States it was initially sold as the ZX-81 under licence by Timex. Timex later produced its own versions of the ZX81: the Timex Sinclair 1000 and Timex Sinclair 1500. Unauthorized ZX81 clones were produced in several countries. The ZX81 was designed to be small, simple, and above all, inexpensive. Video output is for a televisi…

Evidence: 52 • authority: 72

The TI-99/4 and TI-99/4A are home computers released by Texas Instruments (TI) in 1979 and 1981, respectively. Based on TI's own TMS9900 microprocessor originally used in minicomputers, the TI-99/4 was the first 16-bit home computer. The associated TMS9918 video display controller provides color graphics and sprite support which were only comparable with those of the Atari 400 and 800 released a month later. The TI-99 series also initially competed with the Apple II and TRS-80. The calculator-style keyboard of the TI-99/4 and the high price were cited as weak points. TI's reliance on ROM cartridges and their practice of limiting developer information to select third parties resulted in a la…

Evidence: 52 • authority: 72

The history of video games began in the 1950s and 1960s as computer scientists began designing simple games and simulations on minicomputers and mainframes. Spacewar! was developed by Massachusetts Institute of Technology (MIT) student hobbyists in 1962 as one of the first such games on a video display. The first consumer video game hardware was released in the early 1970s. The first home video game console was the Magnavox Odyssey, and the first arcade video games were Computer Space and Pong. After its home console conversions, numerous companies sprang up to capture Pong's success in both the arcade and the home by cloning the game, causing a series of boom and bust cycles due to oversat…

Evidence: 43 • authority: 88

Investigation of Lead, Cadmium, and Copper Levels in Inexpensive and Moderately Priced Eye Shadow Samples Sold in Markets and Stores via ICP-OES. In this study, the levels of lead, cadmium, and copper in inexpensive eye shadows sold in markets and moderately priced eye shadows sold in stores were analyzed using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The accuracy and repeatability of the analytical method were checked using Certified Reference Material (NCS-DC 73350), and the recovery efficiencies obtained were determined as 96.7% for Cu, 98.9% for Pb, and 95.4% for Cd. The relative standard deviation (RSD) of the standard reference material was found to be less…

Evidence: — • authority: 88

Inexpensive home computer used as a versatile digital delay generator. A versatile digital delay generator is described which is built using the widely available C64 Commodore home computer. Fixed delays and delay scans from 1 μs up to 65 ms with 1-μs step size are possible. One can modify the generator program; for instance, a delay scan followed by a number of fixed delay sequences. The speed of a delay scan is adjustable over a very wide range and the accuracy of the delay generation depends uniquely on the system clock accuracy.

Evidence: — • authority: 72

Acorn Computers Ltd. was a British computer company established in Cambridge, England in 1978 by Hermann Hauser, Chris Curry and Andy Hopper. The company produced a number of computers during the 1980s with associated software that were highly popular in the domestic market, and they have been historically influential in the development of computer technology like processors. The company's Acorn Electron, released in 1983, and the later Acorn Archimedes, were highly popular in Britain, while Acorn's BBC Micro computer dominated the educational computer market during the 1980s. The company also designed the ARM architecture and the RISC OS operating system for it. The architecture part of th…

Evidence: — • authority: 72

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, non-technical 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 word processing, playing video games,…

Evidence: — • authority: 72

The history of computing hardware starting at 1960 is marked by the conversion from vacuum tube to solid-state devices such as transistors and then integrated circuit (IC) chips. Around 1953 to 1959, discrete transistors started being considered sufficiently reliable and economical that they made further vacuum tube computers uncompetitive. Metal–oxide–semiconductor (MOS) large-scale integration (LSI) technology subsequently led to the development of semiconductor memory in the mid-to-late 1960s and then the microprocessor in the early 1970s. This led to primary computer memory moving away from magnetic-core memory devices to solid-state static and dynamic semiconductor memory, which greatl…

Evidence: — • authority: 72

The history of personal computers as mass-market consumer electronic devices began with the microcomputer revolution of the 1970s. A personal computer is one intended for interactive individual use, as opposed to a mainframe computer where the end user's requests are filtered through operating staff, or a time-sharing system in which one large processor is shared by many individuals. After the development of the microprocessor, individual personal computers were low enough in cost that they eventually became affordable consumer goods. Early personal computers – generally called microcomputers – were sold often in electronic kit form and in limited numbers, and were of interest mostly to hob…