DATAMATH CALCULATOR MUSEUM
|Date of introduction:||1981||Display technology:||LCD|
|New price:||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:||5374901|
|Batteries:||2*LR54||Date of manufacture:||year 1981|
|AC-Adapter:||Origin of manufacture:||Taiwan|
|Precision:||8||Integrated circuits:||Sharp LI3033MT|
|Program steps:||Courtesy of:||Joerg Woerner|
Unisonic LC-7311BK calculator look familiar to you?
Dismantling the featured LC-7311BK manufactured in 1981 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 Unisonic LC-7311BK calculator brought our attention to a small mark reading MK65-6, we spotted this PCB-Mark already with near identical offspring like the IMA LC 688, NSC Novus Electronics NS220, TI-1755 and TI-1756 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-7311BK 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.
IIf you have additions to the above article please email: firstname.lastname@example.org.
© Joerg Woerner, March 15, 2020. No reprints without written permission.