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 |
Memories: | 1 | ||
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
Cal-Comp
Electronics. We started compiling a list of the
PCB-Marks on calculators manufactured by OEMs for Texas Instruments.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, October 10, 2003. No reprints without written permission.