ground relays

Mark Handley of UCL explains, with simulation visualizations, how early Starlink satellites without inter-satellite links could still give low-latency wide-area communication by hopping via ground relays. He shows it can beat fibre on many long paths.

Rick Hartley gives a roughly two-hour live training on proper grounding in PCB design. He explains how energy actually flows in the space between conductors, and how that governs noise, EMI, return paths and signal reflections.

A Technology Connections video on how ground-source (geothermal) heat pumps work and why they hold efficiency in winter. It also covers related heat pump information, and the description notes air-source heat pumps have since improved.

Kirsten Dirksen tours the underground ferro-cement dome home of Paula and Bill Lishman, the family behind the geese-led flight story. The skylit earth-sheltered house stays warm below the frost line.

Tom Scott and Matt Parker investigate some of the small deceptions and oddities of the London Underground, such as misleading signage and map distortions.

Kirsten Dirksen profiles Steve Rees, who buried two shipping containers to build an earth-cooled, off-grid 640 sq ft home in Northern California for about $30,000, solar included.

A 39-minute BBC documentary, built from earlier British Transport Films footage, on how the London Underground's Victoria Line was dug in the 1960s.

Geoff Marshall explains a running gag about London Underground stair signs claiming that the climb equals 15 floors, regardless of how many steps there actually are.

David Beazley's PyCon 2019 tutorial derives the lambda calculus from the ground up in Python, using only single-argument functions. He builds booleans, numerals and more with no other language features.

A 24-hour loop of Star Trek TNG starship engine ambience, meant as background sound for relaxing, sleeping or concentrating.

A live, overdub-free performance of 'Lingus' by Snarky Puppy, from the 'We Like It Here' DVD recorded in Utrecht. It features a Cory Henry keyboard solo.

The first lecture of Jordan Peterson's 2017 Maps of Meaning course, setting out the Cold War context for his theory of belief and culture. He introduces the narrative structure of culture and archetypal characters for the individual, the known and the unknown.

Technology Connections takes a long, detailed look at how a 1970s electromechanical pinball machine works, from relays to stepper motors and mechanical logic. It is the first part of a series.

Veritasium visits the Micromouse competition, where small autonomous robots race to solve mazes at extreme speed. It covers the competition's technical history, including fans and ground effect enabling very high-g turns.

Sasa Juric's EMPEX talk demonstrates Elixir and Erlang's process model and what makes the BEAM runtime distinctive, such as fault-tolerant parallelism by design.

A documentary following Robert Zubrin and the Mars Society as they push the Mars Direct plan for sending humans to Mars using current technology and local resources. It also covers the clash with NASA's more expensive approach.

Permaculture instructor Andrew Millison visits the village of Garavadi in Maharashtra, India, which took part in the Paani Foundation's Water Cup competition. It shows the water harvesting structures the villagers built in 45 days and how they restored groundwater and the local economy.

A long information session where The Boring Company presents its vision for Loop, an underground high-speed transit system, and the traffic problems it aims to solve. It includes discussion of faster tunnel boring and electrification.

Technology Connections takes apart a 1970 Wurlitzer 3400 jukebox to show how electromechanical relays and switches automated its behavior without a computer.

Tom Scott explains Electrical Network Frequency analysis, where hum from the power grid in a recording is matched against grid logs to date and place it. He talks to a researcher and sets them a challenge.

Technology Connections takes apart the step-by-step electromechanical logic of a 1970s pinball machine. He shows how relays, steppers and switches track state and score without electronics.

A two-minute video of an athlete sprinting against a London Underground Circle Line train between Mansion House and Cannon Street. It shows a runner keeping pace with and beating the train.

Declassified HUD footage of an F-16 whose unconscious pilot is saved by the Automatic Ground Collision Avoidance System. It shows the aircraft pulling out of a dive on its own.

Cloth Map documents Havana's SNET, a community-built private network that Cubans created because internet prices were high. It is used for gaming and sharing.

An 11-minute animated introduction to P vs. NP and the wider landscape of complexity classes, inspired by the Complexity Zoo wiki. It assumes no background in computer science.

Technology Connections explains why car turn signals appear to drift out of sync at stoplights and how thermal and other flasher designs work. It also covers how synchronization could be achieved.

A Last Week Tonight segment on credit reports, explaining their outsized role in people's lives and how often they contain critical errors.

Mark Ferrari, the LucasArts background artist, explains in a GDC 2016 talk how he draws 8-bit graphics. He covers color cycling and palette shifting to create complex animated scenery without frame animation.

Rob Pike shows how the Go text/template lexer is built, using state functions, goroutines and channels. The talk was given at a Google Technology User Group in Sydney in 2011.

Rich Hickey's philosophical talk from the first Clojure Conj in 2010. He argues that good design comes from deliberate, away-from-keyboard thinking, and describes how to feed the background mind so it solves problems.

MIT's Prof. Dennis Whyte explains the ARC/SPARC compact tokamak approach, in which new high-temperature superconducting magnets allow smaller and cheaper fusion reactors. He covers fusion physics, performance trends and the engineering path to net energy.

SethBling shows MarI/O, a program using neural networks and the NEAT genetic algorithm to learn to play Super Mario World. The description links the source code, the paper and background reading.

In this TED talk, Lawrence Lessig argues that American politics is corrupted by Congress's dependence on funding from a tiny fraction of citizens. He uses rapid-fire visuals and calls for a bipartisan push to reclaim the Republic.

Vaclav Smil's talk on historic energy transitions and what they imply for climate investment. He argues that transitions are slow, technology improves gradually, and only absolute cuts in energy use would truly work.

Lawrence Krauss's 2009 talk on the current picture of the universe, how it will end and how it could have come from nothing. It covers the expanding universe, cosmic background radiation and the cosmological constant.

Chris McCord's ElixirConf EU 2019 keynote introducing Phoenix LiveView, which builds interactive server-rendered apps without writing JavaScript. It explains how only changed dynamic parts are sent over a websocket.

Liz Rice live-codes a minimal container runtime in a few lines of Go at GOTO Amsterdam 2018. She explains namespaces, control groups and what a host knows about its containers.

Andrew "bunnie" Huang examines how realistic hardware supply chain attacks are, from rogue insiders to nation states, in the wake of the Bloomberg Businessweek report. He explains how undocumented components could be hidden on boards and how hard they are to spot.

Chris Granger, creator of Light Table and the Eve language, gives a Berkeley data science lecture on what computation and programming might look like in ten years. He covers the path that led to Eve and ends with demos.

Veritasium explains, with expert input, that in general relativity gravity is not a force and objects follow straight paths through curved spacetime, including why standing on the ground means you are accelerating.