How Pong's inventor gave Woz a hack to bring color to the Apple II

In 1977, Steve "Woz" Wozniak used a neat hack to bring color to the Apple II computer. According to IEEE Spectrum, the obscure trick, called NTSC artifact color, "allows digital systems without specialized graphics hardware to produce color images by exploiting quirks in how TVs decode analog video signals." That hack later was employed by the IBM PC, Radio Shack TRS-80, and other early home computers. But how did Woz learn about it? Turns out, videogame legend Al Alcorn, inventor of Pong, turned Woz onto the hack. From IEEE Spectrum:

Stephen Cass: Analog NTSC televisions generate color by looking at the phase of a signal relative to a reference frequency. So how did you come across this color test tool, and how did it work?

Al Alcorn: When I was 13, 14, my neighbor across the street had a television repair shop. I would go down there and at the same time, I had my father sign me up for an RCA correspondence course on radio and television repair. So, by the time I got to Berkeley, I was a journeyman TV repairman and actually paid my way through college through television. In one repair shop, there was a real cheap, sleazy color bar generator [for testing televisions]. And instead of doing color properly by synthesizing the phases and stuff like that, it simply used a crystal that was 3.58 megahertz [the carrier frequency for the color signal] minus 15.750 kilohertz, which was the horizontal scan frequency. So it slipped one phase, 360 degrees, every scan line.

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You can run DSL over wet string

ADSL was a miracle when it debuted, delivering high speeds over old copper, thanks to a protocol that was so adaptable to suboptimal media that it was said it could run "over a piece of wet string." Read the rest

Debunking the NYT feature on the wastefulness of data-centers

This weekend's NYT carried an alarming feature article on the gross wastefulness of the data-centers that host the world's racks of server hardware. James Glanz's feature, The Cloud Factory, painted a picture of grotesque waste and depraved indifference to the monetary and environmental costs of the "cloud," and suggested that the "dirty secret" was that there were better ways of doing things that the industry was indifferent to.

In a long rebuttal, Diego Doval, a computer scientist who previously served as CTO for Ning, Inc, takes apart the claims made in the Times piece, showing that they were unsubstantiated, out-of-date, unscientific, misleading, and pretty much wrong from top to bottom.

First off, an “average,” as any statistician will tell you, is a fairly meaningless number if you don’t include other values of the population (starting with the standard deviation). Not to mention that this kind of “explosive” claim should be backed up with a description of how the study was made. The only thing mentioned about the methodology is that they “sampled about 20,000 servers in about 70 large data centers spanning the commercial gamut: drug companies, military contractors, banks, media companies and government agencies.” Here’s the thing: Google alone has more than a million servers. Facebook, too, probably. Amazon, as well. They all do wildly different things with their servers, so extrapolating from “drug companies, military contractors, banks, media companies, and government agencies” to Google, or Facebook, or Amazon, is just not possible on the basis of just 20,000 servers on 70 data centers.

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