*1) The model J comptometer was introduced in 1926 and was easily distinguished from its predecessors by its green key tops. Click here to see a film clip courtesy of The Institute for Mathmatics and Computer Science at Ludwigsburg, Germany,
*2) A portable, full keyboard, direct key-driven machine, designed for high-speed calculations involving all branches of mathematics. It is duplex in operation, in that it will add in more than one column at a time, each column having the capacity to add, receive and carry simultaneously.
Content without guarantee! (UK); Inhalt Ohne Gewähr! (DL)
| Type name / number: | Adding Machine, Comptometer - model J |
| Production / SN: | J314579 *1) |
| Calculating principle: | Rocking Segment / Direct adding (key driven) |
| Calculating functions: | Add, Subtract with nine complement |
| Input accuracy | 10 digits |
| Calculating accuracy: | 11 digits |
| Extra's: | Display of input- and total / result number |
| Designer: | Mr. E. Felt |
| Production year: | 1926 - 1930 |
| Case material: | Copper plated metal. Bottom RVS. |
| Weight: | 9,2 Kg |
| External links: | |
| Previous owner: | Luigi Serrapiglio, Lehrte / Sieverhausen, germany |
| Cosmetic imperfections: (I accuse no one) |
one green key top 6, and the red extra key (function ?) are missing. |
| Date of receiving: | 2010 - july |
| Machine story: | Fully functional on arrival. Only cosmetic cleaning. Probably not opened before, relatively clean inside. |