Radio Shack statesman EC-423

Date of introduction:  1988 Display technology:  LCD
New price:   Display size:  8
Size:  4.9" x 2.8" x 0.28"
 125 x 70 x 7 mm3
Weight:  2.1 ounces, 59 grams Serial No:  
Batteries:  LR54  Date of manufacture:  mth 06 year 1988
AC-Adapter:   Origin of manufacture:  Taiwan
Precision:  8 Integrated circuits:  
Memories:  1    
Program steps:   Courtesy of:  Joerg Woerner

Does this EC-423 calculator look familiar to you? Please compare it with the Technico SB-806M.

Dismantling this EC-423 calculator manufactured in June 1988 by Inventa Electronics Corporation of Taipei, Taiwan reveals a typical design of a Far East contract manufacturer centered around an unknown single-chip calculator circuit. Learn how to decipher the 06A8 Date code on the featured calculator.

Inspecting the PCB of this Radio Shack EC-423 calculator brought our attention to a small mark reading SB806II-01C, confirming its close relationship to the Technico SB-806M with its IOSB806-01E mark. We started compiling a list of the PCB-Marks on calculators manufactured by OEMs for Texas Instruments.

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Joerg Woerner, April 6, 2024. No reprints without written permission.