National Museum of American History
P.O. Box 37012, MRC 601
Constitution Ave., between 12th and 14th Sts., N.W.,
Washington, D.C. 20013-7012
3 cu. ft. : 9 boxes.
Inventor who worked closely with Kazuo Hashimoto, widely recognized for having developed the telephone answering machine. After Hashimoto died in August 1995, Henderson strove to ensure that Hashimoto’s work would be recognized in the telecommunications and computer industries. In 1996, Henderson and Hashimoto’s widow co-founded PhoneTel Communications, a company dedicated to protecting the patent portfolios of inventors, including Hashimoto. Photocopies of American, Japanese, German, and French patents; photocopied articles, advertisements, news releases, user manuals, buyer’s guides, company analyses, technical references, and an oversize timeline. The collection provides documentation for approximately 80 artifacts, including telephone answering machines, cellular phones, and related wireless devices, which Henderson donated to the Museum’s Electrical Collections holdings. Compiled by Henderson to accompany the artifacts, the materials document the history and development of cellular phones and related wireless devices.