Texas Instruments TI-1798 (Taiwan)

Date of introduction:  1990 Display technology:  LCD
New price:   Display size:  8
Size:  5.4" x 4.1" x 1.15"
 136 x 106 x 29 mm3
Weight:  3.4 ounces, 97 grams Serial No:  
Batteries:  n.a. Date of manufacture:  mth 09 year 1990
AC-Adapter:   Origin of manufacture:  Taiwan (I)
Precision:  8 Integrated circuits:  Toshiba T9731BU
Memories:  1    
Program steps:   Courtesy of:  Joerg Woerner

This stylish small desktop calculator fits somewhere between the TI-1795A and the TI-1775 in Texas Instruments' small desktop calculator portfolio. Main difference is the [GPM] key, a feature not known from the first generation TI-1798 introduced already in 1986.

Dismantling this TI-1798 manufactured in September 1990 by Inventec Corporation in Taiwan reveals a clean design centered around a Toshiba T9731BU single-chip calculator circuit soldered on a double-sided printed circuit board (PCB) and powered by four solar cells. Please notice the empty spot for a small LR54 (LR1130) backup battery - it was used after production of the TI-1798 was shifted to Malaysia and with the identical twin TI-510 manufactured for the European market.

Inspecting the PCB of this TI-1798 calculator brought our attention to a small mark reading 1OSB863-01B and we started compiling a list of the PCB-Marks on calculators manufactured by OEMs for Texas Instruments.

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Joerg Woerner, March 23, 2003. No reprints without written permission.