Calculator and processor chips (3), custom assembled, acrylic / metal / plastic / electronic components, made by Texas Instruments / Professor John Billingsley, Dallas, Texas, United States of America / Toowoomba, Queensland, Australia, c. 1970
This custom assembled calculator consists of solid state components mounted on a brown plastic matrix board; the whole construction is mounted on an amber-coloured Perspex board. The calculator is battery operated and has a finger pad, of which the numbers are totally worn off, for keying in data behind which the components are mounted - including a very early 28 pin processor chip which was a predecessor of the Texas Instruments TMS 1000 type developed in the early 1970s; and above the finger pad is an LED display . On the left side of the Perspex mount is a toggle switch for engaging the current. It uses early integrated circuits. Below the finger pad is an array of transistors, resistors and capacitors and green, red and blue insulated electrical wiring.
There are three extra chips.