Schoenherr Braillotron TI-2550 II

Date of introduction:  1976 Display technology:  Fluorescent and Braille cells
New price:   Display size:  8
Size:  8.3" x 4.7" x 2.8"    
Weight:  2 pounds 6 ounces Serial No:  TI2550/62/78 036721
Batteries:  9 AA-size NiCd Date of manufacture:  year 1978
AC-Adapter:  Custom Origin of manufacture:  Germany
Precision:  8 Integrated circuits:  TMS1071
Memories:   Displays:  Itron FG95A1 and Schoenherr Braille cells
Program steps:   Courtesy of:  Siegfried Kipke

It is very difficult to estimate the date of introduction of this Schoenherr Braillotron based on the Texas Instruments TI-2550 II. This calculator had a short life, introduced October, 1975 it was soon replaced with the TI-2550 III. The company history of Schoenherr GmbH, Horb (Germany) reveals that Mr. Schoenherr founded the company in 1974 and invented the world’s first Braille element that could display and erase Braille characters in 1975. This would match with the timeframe of the TI-2550 II and gives a possible introduction of the Schoenherr Braillotron in 1976.

Only few years later the TI-30 was adapted to the Braillotron and enabled vision impaired people using this best selling scientific calculator. Read more information about the Braille Alphabet.

In 1981 Mr. Schoenherr was killed in an accident and two years later the company was taken over by the "Deutsche Blindenstudienanstalt", a non-profit-organization in Marburg as EHG GmbH and was the production site for Braille displays. Since 1994 the company refirmed as EHG Handy Tech Elektronik GmbH and continued the development of talking scientific calculators with or without braille display.

Galixa Speech  natural voice speech output based on the TI-30 Galaxy
Galixa Speech  natural voice speech output based on the Galaxy 40x
Galixa Braille  natural voice speech output and 10-cell braille display based on the Galaxy 40x

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© Joerg Woerner, December 26, 2002. No reprints without written permission.