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|
|Program steps:||Courtesy of:||Joerg Woerner|
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.
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© Joerg Woerner, March 15, 2020. No reprints without written permission.