File:SWTPC AC30 Cassette Interface July 1976.jpg
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DescriptionSWTPC AC30 Cassette Interface July 1976.jpg |
English: The Southwest Technical Products Corporation (SWTPC) AC-30 tape interface for early personal computers was introduced in May 1976 for $80. When the first home computers were introduced in 1975, floppy disk systems cost $2000. Storing data on audio cassettes was the low-cost but slow option that most hobbyists used. SWTPC designed their AC-30 Cassette Interface to meet the proposed "Kansas City" standard data format. The binary data was recorded using 1200 Hz and 2400 Hz at a 300 baud data rate. At 30 bytes per second it took over 4 minutes to load an 8K file. |
Date | |
Source | Scanned from the July 1976 Byte magazine (inside front cover) by Michael Holley Swtpc6800 |
Author | Southwest Technical Products Corporation, San Antonio, Texas |
Permission (Reusing this file) |
This advertisement did not have a copyright notice and is in the public domain. From the US Copyright Office Circular 3. Page 3, Contributions to Collective Works. (A magazine is a "collective work.")
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Public domainPublic domainfalsefalse |
This work is in the public domain in the United States because it was published in the United States between 1929 and 1977, inclusive, without a copyright notice. For further explanation, see Commons:Hirtle chart as well as a detailed definition of "publication" for public art. Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (50 p.m.a.), Mainland China (50 p.m.a., not Hong Kong or Macao), Germany (70 p.m.a.), Mexico (100 p.m.a.), Switzerland (70 p.m.a.), and other countries with individual treaties.
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Date/Time | Thumbnail | Dimensions | User | Comment | |
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current | 01:04, 30 January 2012 | 2,475 × 3,263 (1.12 MB) | Swtpc6800 (talk | contribs) | =={{int:filedesc}}== {{Information |Description={{en|1= The Southwest Technical Products Corporation (SWTPC) AC-30 tape interface for early personal computers was introduced in May 1976 for $80. When the first home computers were introduced in 1975, flopp |
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Width | 2,475 px |
Height | 3,263 px |
Bits per component |
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Compression scheme | LZW |
Pixel composition | RGB |
Orientation | Normal |
Number of components | 3 |
Horizontal resolution | 300 dpi |
Vertical resolution | 300 dpi |
Data arrangement | chunky format |
Software used | Adobe Photoshop Elements 9.0 Windows |
File change date and time | 17:02, 29 January 2012 |
Color space | Uncalibrated |
Image width | 2,475 px |
Image height | 3,263 px |
Date and time of digitizing | 04:34, 23 April 2005 |
Date metadata was last modified | 09:02, 29 January 2012 |
Unique ID of original document | adobe:docid:photoshop:3ccff63f-b428-11d9-9f72-c7841ab0755e |
Copyright status | Copyright status not set |
IIM version | 2 |