Aristo M 27 (Version 1)

Date of introduction:  November 7, 1972 Display technology:  LED
New price:  DM 466.00 (October 1972) Display size:  8
Size:  3.5" x 2.4" x 1.1"
 88 x 60 x 27 mm3
Weight:  3.0 ounces, 84 grams Serial No:  
Batteries:  5*AA  Date of manufacture:  mth 12 year 1972
AC-Adapter:   Origin of manufacture:  Germany
Precision:  8 Integrated circuits:  TMS0105
Program steps:   Courtesy of:  Joerg Woerner
    Download manual:   (DE: 2.4M Bytes)

Hamburg (Germany) located company Dennert & Pape started already in the year 1872 the business with slide rules. About 100 years later they introduced under the trademark ARISTO with the model M 27 their first electronic pocket calculator.

As of today we know three different versions of the M 27 calculator, they can easily be differentiated by the shape and number of keys:

Version 1: Rectangular design, no CE key
Version 2: Rectangular design, red CE key
Version 3: Rounded design, red CE key

The M 27 based on the calculator-on-a-chip" manufactured by Texas Instruments and found in a lot of other calculators like the Bowmar 901B and even the TI-2500 Datamath. Compared to these products the M 27 is unexpected small and shows an unique design based on a housing with a white bottom, a matte black top and keys in bright yellow and red color.

The next calculator in the ARISTO line is the M 36 sporting an additional memory key. The M 36 could be called the most beautiful calculator and ARISTO kept this design for the next some twenty calculators.

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Joerg Woerner, June 25, 2019. No reprints without written permission.