DATAMATH CALCULATOR MUSEUM
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DATAMATH CALCULATOR MUSEUM |
Texas Instruments TI-1270 (Version 1)
| Date of introduction: | April 21, 1976 | Display technology: | LED-stick |
| New price: | $18.95 | Display size: | 8 |
| Size: | 5.5" x 2.8" x 1.4" 138 x 70 x 35 mm3 |
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| Weight: | 3.9 ounces, 110 grams | Serial No: | 0011144 |
| Batteries: | 9V | Date of manufacture: | wk 30 year 1976 |
| AC-Adapter: | AC9180 | Origin of manufacture: | USA (LTA) |
| Precision: | Integrated circuits: | TMS0974/ZA0355 | |
| Memories: | 1 | Displays: | DIS233G |
| Program steps: | Courtesy of: | Joerg Woerner | |
| Download manual: | 
(US: 2.3M Bytes)
(EU: 3.5M Bytes) |
The
colorful TI-1270 was introduced in April 1976 as a member into the growing TI-1200
family. Is it a basic calculator or a scientific calculator? Compare it with the SR-11,
introduced only 2 years earlier as a powerful scientific calculator.
Within the Datamath Museum the decision was made based on the
technology, we'll keep
it in the Basic Album. If your read more about the calculator chip inside the
calculator you'll notice the similarity to the TI-1200.
Dismantling
the featured TI-1270 with
Date code 3076 LTA and manufactured in July
1976 in Lubbock, Texas reveals a printed circuit board (PCB) identical with the
Hardware Version 3 of the TI-1200 and
TI-1250 calculators. The only change is the
single-chip calculator circuit, we located a TMS0974 instead the TMS0972.
Learn
more about the evolution of the TI-1250 between
June 1975 and its discontinuation in 1977.
With the TI-1270 based on the TMS0974 chips, we consequently differentiate only
two different
printed circuit boards used with the two different versions of the calculator:
| Version | PCB Type |
Date codes From |
Date codes To |
Chip Designation |
Chip Package |
Display | Discrete Components |
| TI-1270 V1 | Type 2 | 2476 LTA | 1277 LTA | TMS0974NL AP |
DIP28 | 8-digits | 1 Jumper Wire |
| TI-1270 V2 | Type 3 | 1577 LTA | 1877 LTA | TMS0974NL AP |
SPDIP28 | 8-digits |
Please notice that the above table lists only TI-1270 calculators manufactured in the Lubbock, Texas facility, both calculators were actually manufactured in Brazil and Italy, too but design changes were typically introduced in the US facilities first.
Preparing our DCM-50A Platform
to allow the Characterization of Single-Chip Calculator Circuits
of the TMS0970/TMC0900 Family, we studied
this TI-1270 calculator manufactured in July 1976 and a
WIZ-A-TRON educational toy assembled in
June 1978. Learn more about the
Bearcat 210 Computer Radio Scanner unleashing the potential of the TMS0970
chip.
Learn more about the different
Product Labels used with the TI-1250
- here at the Datamath Calculator Museum we classify the featured TI-1270 as
Hardware Version 1, PCB Type 2 and Product Label Style 6.
The TI-1270 was manufactured in Italy for the
European market.
We located recently a TI-1270 sporting a almost red faceplate, we are not sure if this color was intended or is simply a quality issue.
A similar calculator was sold as Citation M4988 from the distribution company Western Auto.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, June 20, 2009. No reprints without written permission.