Recently in CONTINUITY

Wednesday, January 27, 2021

Make Your Own Efficient, Long-Lived “Dubai Lamps”

A simple series capacitive dropper allows running higher-wattage LED bulbs at lower current, increasing efficiency, reducing heat generation, and dramatically improving the lifetime of the bulb. These aren't as nice as real Dubai lamps, as featured here on 2020-01-14, since they lack the voltage regulator which eliminates blinking with voltage changes, but they're an improvement on bulbs that over-drive their LEDs and burn out in short order. They do have a poor power factor, but unless you have a smart electric meter that charges for peak current, that won't show up on your electric bill (and besides, most cheap LED bulbs use capacitive droppers anyway and already have low power factors).

One nice thing about LED bulbs is that under-driving them does not change the colour of the light—it purely reduces intensity by limiting the duty cycle.

Posted at 15:14 Permalink

Monday, January 25, 2021

Seventy-Five Years Ago Today: The Last Strong (Mag. 5.8) Earthquake in Switzerland

Posted at 14:51 Permalink

Sunday, January 24, 2021

SpaceX Transporter -1, Second Launch Attempt

After a scrub due to weather yesterday, the second launch attempt for the SpaceX Transporter-1 ride-share mission with 143 satellites bound for Sun-synchronous orbit is scheduled for 15:00 UTC on 2021-01-24.

Update: both fairing halves have been recovered from the sea. (2021-01-24 18:36 UTC)

Posted at 11:50 Permalink

Friday, January 22, 2021

Finally—a Personal Gatling Gun!

It takes 9 mm Glock magazines and isn't, under U.S. law, a machine gun, since you have to manually turn the crank to fire each successive shot. Here is a longer review video.

Posted at 15:38 Permalink

Thursday, January 21, 2021

For 21 Years, No-One in Britain Knew How Long an Inch Was

Posted at 13:20 Permalink

Wednesday, January 20, 2021

Rocket Lab: “Another One Leaves the Crust” Launch

Posted at 14:15 Permalink

Monday, January 18, 2021

US Airways Flight 1549 Ditching in the Hudson River: A Pilot's Analysis

Posted at 16:10 Permalink

Diogenes: “Learn to live on lentils”

Posted at 02:10 Permalink

Sunday, January 17, 2021

A Working Edison Light Bulb from 1896

Posted at 13:57 Permalink

Tuesday, January 12, 2021

Origin of the UNIVAC 1103A Scientific Computer (1953, 1956) ERA, Sperry Rand

The Univac 1101 through 1105, all vacuum tube machines, were the first generation of ERA/Univac scientific computers. The second generation, the transistorised Univac 1107, retained the original 36 bit word length, but re-architected the machine into what would be the 1100/2200 series for decades to come. The story of the 1107 and successors picks up in my Univac Memories archive.

Posted at 19:34 Permalink

So Many Ideas, So Little Time…

Some day, let me tell you the story of MTBF.NET and DATAIMMORTALITY.COM….

Posted at 13:13 Permalink

Monday, January 11, 2021

Monsanto's Plastic “Home of the Future” at Disneyland (1957)

Posted at 14:55 Permalink

Sunday, January 10, 2021

Drilling Out the Microphone in Google's Stadia Game Controller

Posted at 16:31 Permalink

Saturday, January 9, 2021

Most Popular Programming Languages, 1965–2019

Posted at 13:58 Permalink

Friday, January 8, 2021

The Tyranny of Big Publishing

Simon says, “Shut up”.

Posted at 14:44 Permalink

Thursday, January 7, 2021

Jamie Hyneman Can't Delete His Content from Facebook

Posted at 14:51 Permalink

Tuesday, January 5, 2021

Orbital Launch Scorecard, 2020

Jonathan McDowell has published his “Space Activities in 2020” [PDF, 112 pages], with the authoritative data we have come to expect from this publication. Below is a summary I have extracted about orbital launch attempts in 2020 by country. There were a total of 114 orbital launch attempts from Earth in the year, of which 104 succeeded in placing their payloads in orbit. In addition, there was one successful orbital launch from the Moon, China's Chang'e 5 sample return ascender, which is not included in the table below.

Country   Launches   Successes   Failures
China 39 35 4
U.S. 37 34 3
Russia 12 12 0
Europe 10 9 1
New Zealand 7 6 1
Japan 4 4 0
India 2 2 0
Iran 2 1 1
Israel 1 1 0
TOTAL 114 104 10

Because it has become increasingly common to deploy multiple payloads from a single orbital launch, whether constellation deployments such as SpaceX's Starlink or ride-share and cubesat swarms, the statistics for payloads orbited look very different from those of launches. Here are payloads orbited in 2020 by country,

Country   Payloads  
U.S. 979
Europe 129
China 74
Other 57
Russia 22
TOTAL 1261

Posted at 11:50 Permalink

Monday, January 4, 2021

Amazon Has Trucks Filled with Hard Drives and an Armed Guard

Related: “168 AWS Services in 2 Minutes”

Posted at 14:40 Permalink

Sunday, January 3, 2021

“At Home, 2001”—Late 1960s View of the 21st Century Home

From the CBS TV series The 21st Century with Walter Cronkite.

Posted at 16:11 Permalink

Saturday, January 2, 2021

Fourmilab Gridmark: Automated Benchmarks for Second Life

Available for free with full permissions in the Second Life Marketplace, with complete source code published at GitHub.

Posted at 13:52 Permalink