RadioShack - Released in 1972, the EC-100 pocket calculator was RadioShack's first portable basic four-function calculator. The calculator was equipped with a large 8-digit display and could use either four AA's or
![File:Vintage Radio Shack Pocket Electronic Programmable Scientific Calculator, Model EC-4021, LCD Display, Made In Taiwan, Year Introduced - 1991 (16388315827).jpg - Wikimedia Commons File:Vintage Radio Shack Pocket Electronic Programmable Scientific Calculator, Model EC-4021, LCD Display, Made In Taiwan, Year Introduced - 1991 (16388315827).jpg - Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/8/84/Vintage_Radio_Shack_Pocket_Electronic_Programmable_Scientific_Calculator%2C_Model_EC-4021%2C_LCD_Display%2C_Made_In_Taiwan%2C_Year_Introduced_-_1991_%2816388315827%29.jpg)
File:Vintage Radio Shack Pocket Electronic Programmable Scientific Calculator, Model EC-4021, LCD Display, Made In Taiwan, Year Introduced - 1991 (16388315827).jpg - Wikimedia Commons
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