#FRIDEN CALCULATOR HISTORY FULL#
#FRIDEN CALCULATOR HISTORY SERIES#

These seem to be the first items to break. Plastic parts for the Soemtron ETR range of calculators are now around 50 years old and have reached their end of life and have become extremely brittle, none more so than the cabinet latches that hold the two-part covers to the main chassis. January 2018 вЂ“ 3D printed cabinet latches and other spare parts. Timeline вЂ“ Older news from Soemtron (2016-2018).

Similarly the ETR22 of which only 3,203 were built, is also a very rare item. The bottom picture is of an ETR224 printing calculator, a very rare machine as only 526 units were built, whilst there were over 150,000 ETR220s. The two topmost pictures above are of a very good condition Soemtron ETR220 and an ETR222 owned by calculator collector Serge Devidts, for more information see his website.

#FRIDEN CALCULATOR HISTORY FULL#

We have now published and are updating full circuit diagrams (ein schaltplan) of the machine and its inner workings for those of you who are interested - not many probably! but there again this is the Internet, so we hope you drop by again soon. Bookmark this page and come back from time to time and see how we are getting on. Over time we have conserved our original SoemtronВ ETR220 and eventually we hope to get first piece of Eastern Bloc calculator history from the 1960's into full working order, once we can get a suitable power supply into her. Soemtron ETR224 В©2009 RГјdiger Kurth Click image for a larger version After a few days more research and translating some German text off of the baseplate, we worked out what this old dirty corroded hulk was - a Soemtron ETR220 calculator, which turns out to be a very interesting piece of early electronic calculator history from 1960's and 70's German Democratic Republic.

The unit duly arrived, but it was found to be in a very poor state, dirty, rusty and missing its power supply and covers ( photos). Welcome to the only complete collection of Soemtron model ETR22x calculators, a collection which came into being after an old piece of equipment was received from Prague in the Czech Republic, following a Google search for 'core memory' one day during some research into the PDPвЂ“7 range of computers manufactured by the now defunct Digital Equipment Corporation. Soemtron ETR222 В©2007 Serge Devidts Click image for a larger version That one machine was possibly the one delivered to Office and Electronic Machines (OEM) in London, the UK importers. A possible fourth calculator, the 221, was seen in various sales literature of the period and does show and describe the type 221 printing calculator, but it is believed now to have only existed as a single machine for a publicity release (December 2009) in the BГјromaschinen Lexikon, a German publication of the 1960s. BГјromaschinenwerk SГ¶mmerda, the Soemtron branded range of ETR22x calculators encompassed three variants, the ETR220, ETR222 and ETR224 (a model with printout capabilities). Soemtron ETR220 В©2007 Serge Devidts Click image for a larger version

#FRIDEN CALCULATOR HISTORY SERIES#

Soemtron ETR Series Electronic Calculators Skip to navigation

Friden calculator history