Texas Instruments professional distributed by Koh-I-Noor Hardtmuth

Date of introduction:  1977 Display technology:  LED-stick
New price:   Display size:  8 (5 + 2)
Size:  5.8" x 3.1" x 1.4"
 148 x 78 x 36 mm3
Weight:  4.0 ounces, 114 grams Serial No:  429273
Batteries:  9V or RK2 Date of manufacture:  wk 09 year 1978
AC-Adapter:  AC9900/R Origin of manufacture:  Italy (RCI)
Precision:  10 Integrated circuits:  TMS0981
Logic:  AOS - 4 Pending Operations, 15 ()    
Memories:  1    
Program steps:   Courtesy of:  Marie Lisa Collas

Texas Instruments professional? We were really surprised to receive in September 2014 a link from fellow collector Marie Lisa Collas to this unusual looking calculator on the Italian eBay site. It is obvious that the model professional - manufactured for Koh-I-Noor Hardtmuth - is a hybrid of three different products:

The basic functionality is borrowed without any doubts from the TI-30 introduced in 1976
The double-shot injection molded keys are known from the Business Analyst-I
The yellow-brown keyboard plate is... unique

Dismantling this model professional manufactured in 1978 reveals a standard TI-30 printed circuit board (PCB) with the well-known TMS0981 single-chip calculator circuit.

This unique professional followed early in 1978 the model 40 and was replaced already in 1979 with the model 30/super. Don't miss the unique model 45, Studio 29 and colorful SILCA 48.

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Joerg Woerner, October 26, 2014. No reprints without written permission.