DATAMATH CALCULATOR MUSEUM
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DATAMATH CALCULATOR MUSEUM |
Texas Instruments TI-1798
| Date of introduction: | 1985 | Display technology: | LCD |
| New price: | Display size: | 10 | |
| Size: | 4.7" x 5.0" x
0.80" 120 x 128 x 20 mm3 |
||
| Weight: | 3.7 ounces, 110 grams | Serial No: | |
| Batteries: | LR41 + LR54 (30µA) | Date of manufacture: | mth 01 year 1985 |
| AC-Adapter: | Origin of manufacture: | Taiwan (C) | |
| Precision: | 10 | Integrated circuits: | Sharp LI3163 |
| Memories: | 1 | ||
| Program steps: | Courtesy of: | Joerg Woerner |
Texas
Instruments Instruments introduced in the United States of America in 1985/1986 a family of three
very similar calculators:
| • TI-1796: Basic desktop
calculator with 10 digits display capability and "Dual Power" feature • TI-1798: TI-1796 with added clock module • BA-20 Profit Manager: TI-1798 with 6 added keys for COST, SELL, MARGIN calculations |
Dismantling this TI-1798 manufactured in January 1985 by
Compal Electronics in Taiwan
reveals a clean design centered around a Sharp LI3163 single-chip calculator
circuit soldered on a double-sided printed circuit board (PCB) and powered by
four solar cells and a small LR54 (LR1130) backup battery.
Please notice the clock module used with
the TI-1798 and BA-20 Profit Manager next to the calculator display is powered
by its own small LR41 battery. Later designs like the stylish EUROPA
10 powered the clock module directly from the calculator electronics and
omitted the extra battery.
Inspecting
the PCB of this TI-1798 calculator brought our attention to a small mark reading
IOTI1796-01A, we spotted this PCB-Mark already with the TI-1796. We started compiling a list of the
PCB-Marks on calculators manufactured by OEMs for Texas Instruments.
The next generation of the TI-1798
looks completely different.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, April 12, 2005. No reprints without written permission.