30 Sep '14, 7pm

Introducing the World’s Most Precise Clock

Introducing the World’s Most Precise Clock

We typically excite the electrons in an atomic clock with radiation whose frequency doesn’t quite match the transition frequency. That’s because the probability that an electron will be excited follows a bell-curve-like distribution. On the sides of the bell curve, it’s easier to see whether a small change in frequency has occurred because it produces a more detectable effect, more dramatically increasing or decreasing the likelihood that an electron is excited [see illustration, “Finding the Frequency”]. Because of this, during the ordinary operation of an atomic clock, the clock radiation is set so that it has only a 50 percent probability of getting any given atom to make the clock transition. But even if the clock radiation frequency is set precisely at that point, an electron will be in either an excited or an unexcited state after it’s measured. The servo loop will t...

Full article: http://spectrum.ieee.org/aerospace/satellites/introducing...

Tweets

A Nixie Clock with Neon Bulb Logic

hackaday.com 29 Sep '14, 2pm

. This clock was inspired by a few circuits found in a 1967 book Electronic Counting Circuits by J.B. Dance. The theory of...

Google Street View brings the world’s coral reefs to you

Google Street View brings the world’s coral ree...

grist.org 30 Sep '14, 10pm

has been taking a global census of reefs since 2012, and partnered with Google to bring the results to a monitor near you....

World’s Largest “Nixie” Clock at World Maker Faire

World’s Largest “Nixie” Clock at World Maker Faire

hackaday.com 23 Sep '14, 5am

Nixie Rex was created by [Wayne Strattman]. Through his company Strattman Design, [Wayne] supplies lighting effects such a...

World’s most powerful #tank transporter used to move heavy armoured vehicles to Eastern Europe http…

World’s most powerful #tank transporter used to...

army.mod.uk 29 Sep '14, 3pm

The British Army is using the world’s most powerful tank transporter to move the likes of the 62 tonne Challenger 2 Main B...