Jaap Scherphuis | The Ken+Add adding machine @jaapsch2 | Uploaded July 2021 | Updated October 2024, 2 hours ago.
The Ken+Add is a small dial adder, built into a nice metal case that also contains the stylus. It was named after its designer, Kenneth Pangburn, and made from 1950 until about 1958 or so. It used to have a "Magic Slate" inside the lid of the box, which was a waxy rubbery backing with a plastic semi-transparent film laid on top that you could draw on with the stylus. Peeling up the plastic sheet would erase the drawing.
For more information on this and other calculators in my collection, please visit my website:
jaapsch.net/mechcalc
0:00 Introduction
0:32 Addition
1:30 Subtraction
1:55 Clearing
2:26 History
3:20 Magic Slate
4:15 Patents
4:40 Similar machines
5:09 Outro
The Ken+Add is a small dial adder, built into a nice metal case that also contains the stylus. It was named after its designer, Kenneth Pangburn, and made from 1950 until about 1958 or so. It used to have a "Magic Slate" inside the lid of the box, which was a waxy rubbery backing with a plastic semi-transparent film laid on top that you could draw on with the stylus. Peeling up the plastic sheet would erase the drawing.
For more information on this and other calculators in my collection, please visit my website:
jaapsch.net/mechcalc
0:00 Introduction
0:32 Addition
1:30 Subtraction
1:55 Clearing
2:26 History
3:20 Magic Slate
4:15 Patents
4:40 Similar machines
5:09 Outro
