DATAMATH CALCULATOR MUSEUM |

Texas Instruments TI-1255

Date of introduction: | 1976 | Display technology: | LED-stick |

New price: | Display size: | 8 | |

Size: | 5.5" x 2.8" x
1.4" 138 x 70 x 35 mm ^{3} |
||

Weight: | 3.9 ounces, 110 grams | Serial No: | 1242627 |

Batteries: | 2*AA NiCd | Date of manufacture: | wk 16 year 1976 |

AC-Adapter: | AC9130 | Origin of manufacture: | USA (LTA) |

Precision: | Integrated circuits: | ||

Memories: | 1 | ||

Program steps: | Courtesy of: | Joerg Woerner |

Texas
Instruments took in 1976 in conjunction with mathematics educators at two major
universities an initiative to introduce a group of 6 calculators for educational
use. Including the Little Professor,
the limited function ABLE calculator, the colorful TI-1205
and TI-1255, the TI-30 and the
sophisticated SR-51-II, these
calculators helped students understand and use math concepts from kindergarten
through college and career.

The TI-1255 is based on the TI-1250
but includes rechargeable NiCd-batteries instead the standard 9V block battery.
To enhance the readability of the keyboard both the size of the numerals and the
color-scheme was improved.

The featured TI-1255 was manufactured in Spring 1976 and is probably an early evaluation model or was used for sales demonstrations. We found several hints supporting this assumption:

• The calculator is powered with a 9V battery instead the expected two rechargeable AA-sized batteries. • The black label on the back of the calculator reads TI-1250 while a known later model sports a white TI-1255 label. • The earliest calculators of the TI-1205, TI-1255 and TI ABLE trio in the final design (NiCd batteries, white labels) were manufactured in Septem- ber 1976 while this model was assembled already in April 1976. |

The TI-1255 is one of the rarest members in the TI-12xx line and was sold only in the US.

**Fellow collectors - if you own a
Texas Instruments TI-1255 calculator, please report us the serial number
and date code**** from the back of the
calculator for our Database.**

Don’t miss the LADY 1200, a design developed by marketing guys to attack women’s hand-bags.

On September 17, 2009 we were able to celebrate reunion of the calculators featured in the TI Learning Center Sales Leaflet CB-272 including three of the rarest portable electronic calculators.

Find here an excerpt from the TI Learning Center leaflet CB-272 dated 1976:

TI-1255.
A rechargeable, full-function capability calculator with automatic
constant and 4-key memory.
Texas Instruments rechargeable TI-1255 is well-suited for students in fundamental mathematics curricula. It includes the same features as the TI-1205, plus independent memory and change-sign key for entering negative numbers. Using the TI-1255’s versatile memory system, students are able to store intermediate results and answers as they explore secondary level math topics. Students may add to [M+] or subtract from [M-] memory a displayed number without affecting the calculation in process. Stored numbers may be displayed by using memory recall [MR], and the memory can be cleared [MC] without clearing the calculator. Convenient algebraic entry allows students to enter problems in the same order they would write them on paper. A touch of the change-sign key [CS] changes the displayed number from positive to negative or vice versa, and the bright 8-digit display and large keyboard numerals offer good visibility. A
supplement learning package “Calculator Math™ Fundamental
Mathematics”, was developed and tested by the © Texas Instruments, 1976 |

If you have additions to the above article please email: joerg@datamath.org.

© Joerg Woerner, December 5, 2001. No reprints without written permission.