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I am modestly(!) familiar with 4 types of DC voltage output power supplies that offer some degree of regulation to a load. Those are: Zener regulated supply: This has a resistor in series with the incoming / source unregulated DC voltage rail, and a zener diode to ground that fixes the output voltage at the zener voltage. Usually a capacitor to ground at the output is added to help stabilize the voltage, esp. if the load tends to vary a bit. Zener-pnp transistor regulated supply: This adds a transistor and a couple more resistors for more current capability and better...

There are many surplus and refurb chargers / adapters for powering laptop computers on the market these days. Ebay, for example, has loads of them at good prices. And adapters from good brand names like Dell and HP seem to be quite reliable. By their ratings, these would appear to be useful for other projects. However, I was curious as to how consistent the low or no load voltage output was vs. the voltage at rated output. In the case of my Dell DA130PE1-00, a 130 watt adapter, there is just the "simple" rating if 19.5 DC volts @ 6.7...

Bent alkyne (left), diradical (center) and cyclobutadiene molecules under atomic force microscopy. (Leo Gross/IBM) If chemists built cars, they'd fill a factory with car parts, set it on fire, and sift from the ashes pieces that now looked vaguely car-like. When you're dealing with car-parts the size of atoms, this is a perfectly reasonable process. Yet chemists yearn for ways to reduce the waste and make reactions far more precise. Chemical engineering has taken a step forward, with researchers from the University of Santiago de Compostela in Spain, the University of Regensburg in Germany, and IBM Research Europe forcing a...

Zapping the brains of people over 60 with a mild electrical current improved a form of memory enough that they performed like people in their 20s, a new study found... During a sham stimulation, the older group was less accurate than the younger participants. But during and after 25 minutes of real brain stimulation, they did as well. The improvement lasted for at least another 50 minutes after the stimulation ended, at which point the researchers stopped testing. It’s not clear how long the benefit reached beyond that, Reinhart said, but previous research suggests it might go for five hours...

The mean-spirited would call it Darwinism at work. A suspected thief got the shock of his life after apparently trying to steal copper. The man is in a Northern California burn unit after his alleged robbery attempt when horribly wrong. Police were tipped to the crime by a power outage. Soon after the power went out someone called the Rodeo Fire Department to report a telephone pole fire. As crews responded to the fire, they noticed a man walking down the street suffering from visible burns. Investigators with the East Bay Regional Parks District say they think the man was...

CALL TO ACTION: OCTOBER 5th, (through 8th), 2006, WORLDWIDE PROTEST http://www.worldcantwait.net/ Military Corporate Fascism (Military Corporatism) and the fall of the USA from world dominance. Corporate Capitalism is run by SATAN through the use of WAR. Satan loves a bomb. Collateral damage is his term. Military Corporate Capitalism is Godless. The truth will set you free. It is easier to get a camel through the eye of a needle, than a rich man into heaven. (But not impossible.) Corporate Capitalism is run by SATAN through the use of WAR. This is a fundamentally correct statement and those that are fundamental...

Kevin Byrne is a man in the prime of his life who feared he had an old man's problems. Last summer, he was devastated by chronic back pain and thought his hips were about to give out. "I'm thinking, gee, I'm 47 years old and I'm going to need hip replacements already," he said. The hip pain was the beginning of a strange personal odyssey for Mr. Byrne, a technical writer who lives in Newcastle, a bedroom community east of Toronto. He is now convinced his ailment wasn't a sign of premature aging, but an allergy to one of modern...