SWTPC AC30 Cassette Interface



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English: The Southwest Technical Products Corporation (SWTPC) AC-30 tape interface for early personal computers was introduced in May 1976 for $80. Shown with a Sankyo ST-30 cassette recorder, a SWTPC 8K BASIC tape and a TSC 6800 Assembler tape. 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.
Photo taken with a Nikon E3200 camera using tungsten lighting by Michael Holley in September 2005.
Date 30 September 2005(2005-09-30)
Source Transferred from en.wikipedia; transferred to Commons by User:Liftarn using CommonsHelper.
Author Swtpc6800 Michael Holley
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Public domain This work has been released into the public domain by its author, Michael Holley. This applies worldwide.
In some countries this may not be legally possible; if so:
Michael Holley grants anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.

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The original description page is/was here. All following user names refer to en.wikipedia.

  • 2006-02-24 03:39 Swtpc6800 683×394×??? (66450 bytes) Southwest Technical Products Corp. AC-30 Cassette Interface. This recorded computer data in the Kansas City Standard format on audio cassetttes. Introduced in July 1976 and the kit cost $80. Photo by Michael Holley 2005

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Date and time original image was generated 2005:09:30 18:23:14
Date and time image was made digital data 2005:09:30 18:23:14
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