Four pieces of old tropical hardwood with holes and numbered 1 to 10 and 100 to 1000. Obviously an ancient counting or memory device because of a big peg and a small one which can be put into the holes.
Calculating cilinders
A lot of different and sometimes company-dedicated cilinders were in use in the 60s. It is a slide rule variation on which 2, 3 of 4 rings can be turned to calculate weights, currency, dates, conversions, lengths and simple calculations as on a sliderule. In the middle: the Universal Circle Metric Converter and to the right: the Universal Circle Slide rule of Control Data.
Circuit from an old computer
Given to me in 1962 by a retired IBM Engineer this electronic circuit is probably from an old (1st. gen.) IBM 604 computer. The vacuum tubes served as diodes and are from different vendors: General Electric, Telefunken, AEG, IBM, etc. After WO II these vulnerable and low-performance computers with small memories were sold or hired out by IBM for much money along with punchcard readers and collators (sorters). Intense heat from the tubes often caused more down time than up time.
Calculator for Blind People
This Texas Instruments (TI-30) electronic calculator has been modified for blind and visually handicapped persons. The machine is called 'Braillotron' by the manufacturer: Schönherr in Stuttgart, Germany. On top of the calculator the braille line for tactile feedback. Right below a push button to reset: pull back all braille-pins.
