Solution to a geometry puzzle
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Orrell's Quick Wall Paper Calculator
A trade show freebie which is almost a slide rule
read moreMy proof of Descartes's theorem was just published
Where to find my latest publication
read moreAnother little puzzle
A little puzzle involving nesteed circles
read moreA simple geometry puzzle
A little puzzle involving a circle with inscribed squares
read moreA Cubic Spline for Animation
Developing a simple linear program for animating an LED string
read moreA Problem in Optimal Transport
We show why convex cost functions lead to certain types of solutions to optimal transport problems, using a simple example.
read moreAn intuitive proof of the Descartes circle theorem
An original, intuitive proof of the Descartes circle theorem.
read moreReturn to Battleship
Reflecting on an old coding project, and what I would do differently now.
read moreDecoding a multiplexed LCD
Figuring out which segments are wired where on the TI-30Xa
read moreLessons from the Xanthippe circuit board
Regrets and insights brought from the Xanthippe circuit board
read moreRevisiting Apollonian gaskets
A better way of generating Apollonian gaskets.
read moreIntroducing Xanthippe
A formal introduction to my calculator validator
read moreA 3D-printed Planimeter For Use In Classrooms
A simple 3D-printable design for a planimeter, suitable for making a class set.
read moreReading a Multiplexed LCD Signal
I want to read the signal going to the display of a TI-30Xa calculator. The display has 112 segments, multiplexed in a 4x28 configuration. How can we recover the displayed values from just those 32 pins?
read moreReverse-Engineering a Matrix Keypad
The process of figuring out the layout of a keypad without looking at it directly.
read moreReflections on wiring a calculator
Some thoughts on soldering, connectors, circuit repair, and test setups.
read moreReview: How to Do Nothing by Jenny Odell
I liked this book, it makes good points in interesting ways
read moreA Two Bit Analog-Digital Converter
A surprisingly simple circuit gives a reliable two bit analog-digital converter using only one integrated circuit chip.
read moreMeasures of Bimodality
What are the most popular ways to measure the bimodality of a sample from a random variable?
read morePinball Science
an old game I enjoyed as a kid, which is now hard to install.
read moreWhat's Inside "The REAL Cotton Candy Maker"?
Tracing out the circuit of an old, constantly-breaking toy.
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