DATAMATH CALCULATOR MUSEUM
Texas Instruments TI-1200 (Repair Label)
|Date of introduction:||March 1975||Display technology:||LED-stick|
|New price:||$24.95||Display size:||8|
|Size:|| 5.5" x 2.8" x 1.4"
138 x 70 x 35 mm3
|Weight:||3.9 ounces, 110 grams||Serial No:||1037019|
|Batteries:||9V||Date of manufacture:||Factory repaired wk 27 year 1975|
|AC-Adapter:||AC9180||Origin of manufacture:||USA|
|Precision:||8||Integrated circuits:||TMS0952 or TMS0972|
|Program steps:||Courtesy of:||Joerg Woerner|
(US: 1.3M Bytes)
(US: 1.3M Bytes)
(EU: 3.5M Bytes)
Instruments introduced the TI-1200/TI-1250
in 1975, right at the beginning of the
Calculator War. Prized in 1975 still around US $20, or about $65 in 2000's
money and a whooping $100 in 2020's money, these basic calculators were not yet
considered to be commodities and Texas Instruments consequently repaired them.
We feature this repaired TI-1200 due to its special label on the backside of the
calculator that omits the serial number and country of manufacturing.
Dismantling the featured TI-1200 with Repair Date code 275 (July 1975) and manufactured around May 1975 in Lubbock, Texas reveals a very efficient and cost-optimized design with a single-sided printed circuit board (PCB) centered around a TMS0952 single-chip calculator circuit based on the TMS1000, the World's first Microcomputer and shows some obvious signs of repair.
Early calculators of the TI-1200 and TI-1400 family use a
keyboard with a 6*4 matrix having only 5 key-dome rows populated for a total of 20 keys. The unused key
hidden with the metal faceplate and removing it would add the missing [CS] or
Later the keyboard was cost-optimized to a 5*4 matrix. Find two of them in the Speak
& Spell introduced in the year 1976.
The TMS0952 was soon replaced with the TMS0972, a pin-compatible design dropping the additional resistors and capacitor and further reducing the manufacturing costs of the TI-1200 series.
Learn more about the
evolution of the TI-1200 between March 1975 and its discontinuation in 1977.
Learn more about the different Product Labels used with the TI-1200 - here at the Datamath Calculator Museum we classify the featured TI-1200 as Hardware Version 1, PCB Type 1 and Product Label Style 5, Repair Label.
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© Joerg Woerner, June 29, 2021. No reprints without written permission.