Digitronic‑M Calculator Repair

During my wan­der­ings on eBay I came across this 12 dig­it dis­play Digitronic‑M cal­cu­la­tor. It was an auc­tion list­ing start­ing at $0.99 with a real­ly low ship­ping cost, and the sell­er list­ed it as “works great!”. I put in a very low bid on it, not expect­ing to win it, but it turned out I was the only bid­der. That was the good part of the transaction.

Eico Digitronic‑M after cleanup and repairs
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Eiko Unitrex 1200M Calculator Refurbishment

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.

Eico Unitrex 1200M cal­cu­la­tor 12 dig­its plus memory
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