DATAMATH CALCULATOR MUSEUM |
Texas Instruments TI-508
Date of introduction: | 1989 | Display technology: | LCD |
New price: | Display size: | 8 | |
Size: | 4.7" x 4.1" x
1.0" 120 x 106 x 25 mm3 |
||
Weight: | 3.0 ounces, 86 grams | Serial No: | |
Batteries: | n.a. | Date of manufacture: | mth 06 year 1990 (B) |
AC-Adapter: | Origin of manufacture: | Taiwan (C) | |
Precision: | 8 | Integrated circuits: | Sharp LI3135MS |
Memories: | 1 | ||
Program steps: | Courtesy of: | Joerg Woerner |
Nevertheless the identification number TI-508 points to a handheld calculator, it could be called a "small desktop" machine. The calculator is based on the earlier TI-502.
Dismantling
this TI-508 manufactured in June 1990 by Cal-Comp
Electronics , an OEM (Original Equipment Manufacturer) in Taiwan, reveals a
clean design centered around Sharp LI3135MS single-chip calculator circuit
soldered on a double-sided printed circuit board (PCB) and powered by solar
cells.
Inspecting the PCB of this TI-508 calculator brought our attention to a small mark reading
SD9T-10, most likely a reference to Type
Small Desktop 9, Texas Instruments and Revision 1.0
of the design (schematics and layout). We spotted this PCB-Mark already with the first
TI-1795 and its near identical offspring
Radio Shack EC-2006A and started compiling a list
of the PCB-Marks on calculators
manufactured by OEMs for Texas Instruments.
An identical calculator was sold as TI-1795
in the Americas, an
identification number clearly borrowed from the desktop line.
Production of the TI-508 and its twin TI-1795 was shifted in 1991 from Taiwan to Thailand, just before the slightly redesigned TI-508 PLUS was introduced.
Don't miss the odd TI-808 and the TI-510.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, December 5, 2001. No reprints without written permission.