DATAMATH CALCULATOR MUSEUM |
IMA LC 688
Date of introduction: | 1982 | Display technology: | LCD |
New price: | $8.99 (SRP Sep. 1982) | Display size: | 8 |
Size: | 3.9" x 2.4" x 0.25" 100 x 60 x 6 mm3 |
||
Weight: | 1.6 ounces, 44 grams | Serial No: | 8571527 |
Batteries: | 2*LR54 | Date of manufacture: | year 1982 |
AC-Adapter: | Origin of manufacture: | Taiwan | |
Precision: | 8 | Integrated circuits: | Sharp LI3033MT |
Memories: | 1 | ||
Program steps: | Courtesy of: | Joerg Woerner |
Does this
IMA (International Merchandising Associates) LC 688 calculator look familiar to you?
Dismantling
the featured LC 688 manufactured around 1982 by an unknown
OEM (Original Equipment Manufacturer) in Taiwan reveals a clean design
centered around a Sharp LI3033MT single-chip calculator circuit soldered on a
double-sided printed circuit board (PCB) and powered by two small LR54 (LR1130) batteries.
Inspecting the PCB of this
IMA LC 688 calculator brought our attention to a small mark reading MK65-A,
we spotted this PCB-Mark already with near identical offspring like the NSC
Novus Electronics NS220, TI-1755,
TI-1756 and Unisonic
LC-7311BK
and suspect to locate it in the Technico MK 65, too. Plus the Asaflex MK 653, Benkson CAL-20, Levi MK 1652, MBO MK65, M-Office MK650, Olympia MK 65, Privileg Senator, Radio Shack EC-376, Satek MK 652 and Unisonic LC-7311M. Based on the PCB-Marks located with the
TI-2130 and its twin Technico
F-800 we are almost positive that
the LC 688 and its siblings were manufactured by
Inventa Electronics Corporation
of Taipei, Taiwan. 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, March 15, 2020. No reprints without written permission.