DATAMATH CALCULATOR MUSEUM
Texas Instruments TI-1788 III
|Date of introduction:||1984||Display technology:||LCD|
|New price:||Display size:||8|
|Size:||3.9" x 2.3" x 0.3"|
|Weight:||1.6 ounces||Serial No:||10108034|
|Batteries:||2*LR43||Date of manufacture:||mth 09 year 1985|
|AC-Adapter:||Origin of manufacture:||Taiwan (C)|
|Precision:||8||Integrated circuits:||Toshiba T6798S|
|Program steps:||Courtesy of:||Joerg Woerner|
|Download manual:||(DE, GB: 1.4 MByte)|
The TI-1788 III combines the clock and alarm time function known from the TI-1788 II with a whole set of additional functions and includes:
|• 8-digit calculator including full memory
• Clock with alarm time and buzzer
• World Time
• Calendar with Day of Week function
• Stopwatch with intermediate results
• Conversion capability (multiplies with and divides by a constant)
Compared with the TI-1790
introduced about 6 years earlier size and weight was reduced dramatically.
Dismantling the featured TI-1788 III manufactured in September 1985 by a non-disclosed Original Equipment Manufacturer (OEM) reveals a clean design centered around a Toshiba T6798S single-chip calculator circuit soldered on a double-sided printed circuit board (PCB) and powered by two small LR43 batteries. The only additional components are the 8-digit LC-Display and a small buzzer for the alarm. We know the Toshiba T6798S chip already from the Canon LC-64T dropping the [WT] key (World Time) to use a more traditional 5x5 keys layout allowing a smaller package of the calculator.
Inspecting the PCB of this TI-1788 III calculator brought our attention to a small mark reading CC-31T-11, similar marks could be found with the TI-1788 and TI-1788 II. We are almost positive that the TI-1788 III was manufactured by Compal Electronics. We started compiling a list of the PCB-Marks on calculators manufactured by OEMs for Texas Instruments.
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© Joerg Woerner, October 10, 2003. No reprints without written permission.