DATAMATH CALCULATOR MUSEUM
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DATAMATH CALCULATOR MUSEUM |
Texas Instruments TI-40
| Date of introduction: | 1982 | Display technology: | LCD |
| New price: | $25.00 | Display size: | 8 (5+2) |
| Size: | 5.8" x 3.1" x 0.9" | ||
| Weight: | 3.9 ounces | Serial No: | |
| Batteries: | 2*LR44 | Date of manufacture: | wk 50 year 1981 |
| AC-Adapter: | Origin of manufacture: | Italy | |
| Precision: | Integrated circuits: | CD4507 or CD4557 | |
| Memories: | 1 | ||
| Program steps: | Courtesy of: | Joerg Woerner |
This
TI-40 looks somewhat odd. If you compare it with the TI-55-II
you notice that one line of keys is missing. The advantage of the TI-55-II
compared with the slimline calculators like the original TI-35
was the bigger display and the extra line of keys. And now this one!
The
electronics and the display of the slimline calculator in the slanted housing.
Difficult to understand but on the production line in 1982. Roughly four years later we got with the slanted TI-53 again a hybride between a slimline and slanted calculator. The picture at the right gives you the internal construction of an early TI-40. Later calculators (e.g. Bill Wood's TI-40 manufactured wk 24 year 1982 in USA) make use of the well known CD4557.
Read more about the "CD4507+50=CD4557" calculation here.
If you are interested in the calculating accuracy of scientific calculators don't miss the Calculator forensics.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, December 5, 2001. No reprints without written permission.