Month: May 2023

Another bar­gain price pur­chase of an Eico Unitrex 1200M cal­cu­la­tor. This mod­el also uses the same CT5005 LSI cal­cu­la­tor on a chip IC as the APF Mark XII Calculator, but is note­wor­thy because of the rela­tion­ship of Eico with Cal-Tex Semiconductor, Inc., the man­u­fac­ture of the IC chip. The 1200M was the first cal­cu­la­tor to use a sin­gle LSI IC with inte­grat­ed mem­o­ry. It also has a beau­ti­ful 12 dig­it Neon gas-dis­charge display.

Continue read­ing “Eiko Unitrex 1200M Calculator Refurbishment”