Local Infrastructure: The Devil is in the Details

About two months ago I rode my bike to work like any other day, but on the way home a construction project seemed to have spontaneously started at one of the bridges that I pass over. Three lanes had merged into one which, for a federal highway, seemed like a poorly planned traffic pattern for a such a major construction project. As it happens, about an hour after I biked across this bridge that morning both outside sections of the bridge fell into the water. There was no other physical damage that seemed to explain why parts of a bridge …read more http://pje.fyi/Q9pXs0

Paul Jacob Evans

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JST Is Not A Connector

When reading about cool projects and products, it’s common to see wiring plugs labelled “JST connector.” This looks fine until we start getting hands-on and begin hacking things together. Inevitably we find the JST connector from one part fails to fit in the JST connector of another. This is the moment we learn “JST” is not a connector specification. It is short for Japan Solderless Terminals Manufacturing Company, Ltd. A company whose history goes back to 1957 and their website (styled in 1999) lists hundreds of different types.

We can simplify to “JST connector” when chit-chatting about projects. But when …read more http://pje.fyi/Q7s92s

Paul Jacob Evans

Living On The Moon: The Challenges

Invariably when we write about living on Mars, some ask why not go to the Moon instead? It’s much closer and has a generous selection of minerals. But its lack of an atmosphere adds to or exacerbates the problems we’d experience on Mars. Here, therefore, is a fun thought experiment about that age-old dream of living on the Moon.

Inhabiting Lava Tubes

The Moon has even less radiation protection than Mars, having practically no atmosphere. The lack of atmosphere also means that more micrometeorites make it to ground level. One way to handle these issues is to bury structures under …read more http://pje.fyi/Q5fkmB

Paul Jacob Evans

The Perils of Developing the Hackaday Superconference Badge

In case you haven’t heard, the best hardware conference in the world was last weekend. The Hackaday Superconference was three days of hardware hacking, soldering irons, and an epic hardware badge. Throw in two stages for talk, two workshop areas, the amazing hallwaycon and the best, most chill attendees you can imagine, and you have the ultimate hardware conference.

Already we’ve gone over the gory details of what this badge does, and now it’s time to talk about the perils of building large numbers of an electronic conference badge. This is the hardware demoscene, artisanal manufacturing, badgelife, and an exploration …read more http://pje.fyi/Q18BMw

Paul Jacob Evans

Sferics, Whistlers, and the Dawn Chorus: Listening to Earth Music on VLF

We live in an electromagnetic soup, bombarded by wavelengths from DC to daylight and beyond. A lot of it is of our own making, especially further up the spectrum where wavelengths are short enough for the bandwidth needed for things like WiFi and cell phones. But long before humans figured out how to make their own electromagnetic ripples, the Earth was singing songs at the low end of the spectrum. The very low frequency (VLF) band abounds with interesting natural emissions, and listening to these Earth sounds can be quite a treat.

Long, Long Waves

The VLF band is roughly …read more http://pje.fyi/PzYGw6

Paul Jacob Evans

Teardown With A Twist: 1975 Sinclair Scientific Calculator

When writing a recent piece about Reverse Polish Notation, or RPN, as a hook for my writing I retrieved my Sinclair Scientific calculator from storage. This was an important model in the genesis of the scientific calculator, not for being either a trailblazer or even for being especially good, but for the interesting manner of its operation and that it was one of the first scientific calculators at an affordable price.

I bought the calculator in a 1980s rummage sale, bodged its broken battery clip to bring it to life, and had it on my bench for a few years. …read more http://pje.fyi/Pym9NZ

Paul Jacob Evans

Fail of The Week — Accidental Demagnetization

There’s a trick in the world of plastic enclosures. The threaded insert is a small cylinder of metal with threads on the inside and a rough edge on the outside. To make a plastic part with a hole for securely connecting bolts that can be repeatedly screwed without destroying the plastic, you take the threaded insert and press it (usually with the help of a soldering iron to heat the insert)  into a hole that’s slightly smaller than the insert. The heat melts the plastic a little bit and allows for the insert to go inside. Then when it cools …read more http://pje.fyi/PxxdhP

Paul Jacob Evans