Watching the Clocks

Setting VCR clocks automatically created a lot more problems than anyone realized

13 min read

In October, IEEE Spectrum reported on two problems confronting some U.S. users of videocassette recorders having automatically setting clocks ["Does anybody really know what time it is?," by Tekla S. Perry, October, pp. 26-28]. In some places they were seriously fast and in others seriously slow. The so-called autoclocks get their information from a digital time stamp sent by most Public Broadcasting System (PBS) stations during the television screen's vertical blanking interval. Sometimes called the XDS (extended data service) signal, for a time it was also being sent out by some Fox network affiliates. A VCR with an autoclock searches for the time signal, starting with the lowest-frequency channel in its vicinity and moving higher. Once it finds the signal, it stops searching

In San Jose, Calif., for example, some viewers were faced with clocks that were 24 minutes fast, because the time stamp being sent by a local PBS affiliate was incorrect. In other parts of the country, some viewers were faced with clocks one, two, or three hours slow, because some Fox affiliates were passing along time stamps set to the local time in Los Angeles. These errors were fixed last summer.

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Engineers Are Working on a Solar Microgrid to Outlast Lunar Nights

Future lunar bases will need power for mining and astronaut survival

4 min read
A rendering of a lunar base. In the foreground are rows of solar panels and behind them are two astronauts standing in front of a glass dome with plants inside.
P. Carril/ESA

The next time humans land on the moon, they intend to stay awhile. For the Artemis program, NASA and its collaborators want to build a sustained presence on the moon, which includes setting up a base where astronauts can live and work.

One of the crucial elements for a functioning lunar base is a power supply. Sandia National Laboratories, a research and development lab that specializes in building microgrids for military bases, is teaming up with NASA to design one that will work on the moon.

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Trilobite-Inspired Camera Boasts Huge Depth of Field

New camera relies on “metalenses” that could be fabricated using a standard CMOS foundry

3 min read
Black and white image showing different white box shapes in rows

Scanning electron microscope image of the titanium oxide nanopillars that make up the metalens. The scale is 500 nanometers (nm).

NIST

Inspired by the eyes of extinct trilobites, researchers have created a miniature camera with a record-setting depth of field—the distance over which a camera can produce sharp images in a single photo. Their new study reveals that with the aid of artificial intelligence, their device can simultaneously image objects as near as 3 centimeters and as far away as 1.7 kilometers.

Five hundred million years ago, the oceans teemed with horseshoe-crab-like trilobites. Among the most successful of all early animals, these armored invertebrates lived on Earth for roughly 270 million years before going extinct.

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Reduce EMI and EMC Issues with Engineering Simulation Software

Save time and money all while delivering accurate and reliable results

1 min read
Reduce EMI and EMC Issues with Engineering Simulation Software

Electronic components and systems exist today in nearly all consumer and industrial products. A major design consideration in all electronics is electromagnetic interference (EMI) and compatibility (EMC). EMI and EMC issues are complex. They can be hard to detect and can be taxing to a design. With the use of engineering simulation software, design engineers can mitigate issues before entering the prototype testing phase. Avoiding the test-retest cycle with simulation can help save time and money all while delivering robust and reliable products.