Additional Pictures 


The sales box of a very early Radio Shack EC-100 calculator shows its manufacturing date.

This Radio Shack EC-100 (Version 1) was manufactured in September 1972 by Texas Instruments.

A Radio Shack EC-100 (Version 1) with the [+=] and [-=] keys inserted the wrong way.

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Joerg Woerner, October 31, 2021. No reprints without written permission.