4017 Led Pattern-Flasher

 

The circuit uses a 555 timer oscillator to supply clock pulses of a variable frequency to the 4017 decade counter. The decade counter only needs to have three outputs so the fourth output goes into the reset pin to start the cycle all over again. The central red led is always on. Each row of four leds flash in sequence giving the impression that the light is rotating. It is an idea that works very well giving an eye-catching display. It will run continuously for three hours with a standard pp3 battery.   www.bgocled.com 

Low-battery indicator with LED flasher

Typical low-battery indicators simply turn on an LED when the battery voltage drops below a certain value. Such circuits actually accelerate the battery’s extinction by drawing excessive current. This circuit draws a mere 1 mA in its standby mode and averages only 20 m A when activated. The low current imposes a minimal burden on any battery circuit.   www.bgocled.com

Pulitzer winner: I’m here illegally

Former Washington Post journalist Jose Antonio Vargas — who won a Pulitzer Prize with the paper for his reporting on the Virginia Tech tragedy in 2007 — made a shocking admission this morning: He’s an illegal immigrant.
Vargas made the confession by way of a remarkable personal essay in the New York Times Magazine, titled “My Life as an Undocumented Immigrant.” His story began at the age of 12, when he emigrated from the Philippines to live with his grandparents in California. At the time, Vargas says, he didn’t know anything was amiss. He says he discovered his illegal status at 16, when he went to the DMV to obtain a learner’s permit — only to be informed by a staffer there that his green card was forged.
Still, he continued to assimilate, became a leader in his high school, and earned a scholarship to San Francisco State University. Later came newspaper internships, culminating with a post-grad offer from the Washington Post. Along the way, he cautiously built a network of sympathetic figures who knew his secret and helped him to maintain the facade of citizenship. He’s gone on to build a career for himself as a star journalist, though he says he always felt uncomfortable with the deception.
What finally compelled Vargas to come clean? He says two factors led to his decision: The first was the immense personal toll the secret took. The second was to openly advocate for passage of the decade-old DREAM Act, which would provide a path to citizenship for undocumented immigrants brought to America at a young age, provided they complete their high school education.  Vargas quietly left his post as a senior contributing editor at the Huffington Post last year, and has since founded Define America, a nonprofit organization devoted to raising awareness about immigration reform.
Illegal immigration being the political lightning rod it is, Vargas’ admission was always destined to galvanize a wide range of reactions. Many have lauded the journalist for his courage, exposing himself to the possibility of deportation. (Says Noreen Malone at New York magazine: “The bar just got a whole lot higher for describing personal essays as ‘brave.’”)
On the other hand, Daniel Foster at the National Review is less forthcoming with adulation:

Liberals are coming out of the woodwork to call Vargas’ confession [...] courageous and pioneering. It is certainly the former, and may turn out to be the latter. But in their rush to praise Vargas[...] they conveniently leave out that at the beginning of his story is not one but a series of crimes.
The first part of Vargas’ story — a kid living and loving America for years before his shocking discovery that he has been made complicit in a crime — does indeed elicit sympathy. It’s stories like these that make me open, at least in principle, to something like a narrowly-tailored version of the “DREAM” Act. But the second part of his story, in which a fear- and shame-driven Vargas [...] perpetuated and compounded those crimes, [...] elicits from me nothing like the outpouring of support Vargas is already enjoying on the Left.

(We’ll keep updating this story as responses from the political commentariat continue to trickle in.)
Vargas says he’s been working with attorneys to tackle the legal challenges he’s now almost certain to face. Whatever the outcome, though, he stands defiant against those who would disparage him for his actions. Sitting down with ABC News this morning, Vargas said: “You can call me whatever you want to call me, but I am an American. Nobody can take that away from me.”


UPDATE: More reactions to Vargas’ confession are pouring in. Many, but not all of them, positive.
Matt Yglesias at Think Progress called the Times piece a must-read, and said the warmth with which Vargas has been greeted by many should translate even to those undocumented immigrants who weren’t unwillingly spirited into the country:

But of course even though they don’t quite make for as good a sob story, even people who come over here illegally as adults knowing full well what they’re doing ought to be regarded with sympathy.

Meanwhile, Meredith Jessup at Glenn Beck’s website, The Blaze takes a far less favorable view of Jose, saying:

He may have a Pulitzer, but that doesn’t change the fact that the law has been ignored. Going on television to flaunt the fact he knowingly dodged the law, ostensibly lied to his employers, committed identity fraud, etc. did little to assuage my resentment having come from a family who came to America by knocking on the front door, not sneaking in the back.

Others, like Slate’s libertarian-leaning columnist Jack Shafer, wonder how much Vargas’ employers knew, when they knew, and what kinds of legal repercussions they might now face. Shafer tweeted:

Did Vargas put his employers at the Wash Post and the HuffPost on the hook for breaking the law?

And, in fact, one of Vargas’ former exmployers has been dragged back into the spotlight over the story. The Washington Post, it turns out, had originally been working with Vargas on the story for their weekend Outlook section, but ultimately decided against running it. While no one is entirely certain why they axed the essay — and the Post hasn’t really elaborated on the decision, it’s worth noting that the newspaper did play a fairly substantial role in the piece. Said to The Huffington Post’s Michael Calderone:

Vargas writes how assistant managing editor Peter Perl, then the director of newsroom training, knew about his undocumented status and kept that fact hidden during the journalist’s tenure. It’s unclear whether a Post manager’s role could have led to the paper not running the story (which undoubtedly would have found a home elsewhere and did).
Coratti said that “what Peter did was wrong,” but declined to discuss individual personnel matters.

The ramifications of the story for the Posts (both Washington and Huffington) remains unclear. But the Atlantic Wire’s John Hudson shed some light on what sort of action Vargs himself is likely to encounter, by way of an interview with immigration lawyer David Leopold:

I think he has taken a huge personal risk by coming forward. [...] For example, he admits that he checked ‘U.S. citizen’ on his I-9 forms. This is a serious civil violation for which there is no waiver under the immigration law as written. If it is construed as a false claim to U.S. citizenship, it could lead to criminal sanctions. The same would hold true for knowingly using a false social security card, drivers license etc. There could be a statute of limitations defense depending on when these occurred. But, nevertheless, it could lead to prosecution and or deportation proceedings.

Finally, in a blog post for the NYT Magazine’s 6th Floor Blog, Chris Suellentrop — who Vargas contacted about his story after the Post axed it– recounts the unorthodox circumstances that led to the publication of the piece:

Without having seen the story, I walked into the office of Joel Lovell, one of the magazine’s deputy editors, and closed the door. I told him that Jose Antonio Vargas is an illegal immigrant and that he has a 4,000-word article that tells his story. Should we think about tearing up the book, as we say in the business? [...] Joel thought we should.   www.bgocled.com

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The upside of the selloff

A vote was scheduled next Tuesday for Greek legislators to approve a further €28-billion ($40.24-billion U.S.) in budget cuts and new taxes and back a €50-billion privatization program in order for the euro zone countries to hand over €12-billion in bailout funds that Greece needs to avoid bankruptcy in mid-July.
The TSX Venture Exchange TSXV-I lost 21 points to 1,914.88.
The Canadian dollar CAD/USD-I also finished well off the lows of the session as strength in the greenback moderated following the Greek report. It closed down 0.51 of a cent to $1.0225 (U.S.).
The loonie had fallen as low as $1.018 as worries about economic growth and a possible Greek default pushed traders to the safe haven status of the greenback.
The TSX energy sector fell 1.14 per cent as oil prices CL-FT closed just above $91 a barrel after the International Energy Agency announced the release of 60 million barrels of oil from global strategic reserves in 28 countries because of the ongoing disruption of oil supplies from Libya. The IEA estimates that Libyan unrest removed 132 million barrels of light, sweet crude oil from the market by the end of May.
The August crude contract on the New York Mercantile Exchange fell $4.39 to $91.02 a barrel.
Other factors were at work driving oil prices lower, including Wednesday’s assessment from the U.S. Federal Reserve that the country’s economy is weaker than previously forecast. It lowered its estimate for economic growth this year to 2.9 per cent from 3.3 per cent.
Fed Chairman Ben Bernanke also said the U.S. central bank doesn’t plan to extend a stimulus program of Treasury purchases, known as quantitative easing.
“[The IEA move] had some impact but the market is very nervous about a double dip recession and a lot of commodity prices that went up are coming down hard,” said Azim Hajee, senior trader at Lind Waldock.
“If we go into a recession, it would be quite negative for the commodity markets.”
Mr. Hajee added that oil could “easily” go down to as low as $83 to $85 a barrel while gasoline could retreat 10 cents (Canadian) to 15 cents a litre in Canada.
Commodity prices were also slammed by the higher U.S. dollar.
A stronger greenback usually helps depress commodity prices, which are denominated in dollars, as it makes oil and metals more expensive for holders of other currencies.
The July copper HG-FT contract in New York lost 5 cents (U.S.) to $4.04 a pound but the base metals sector turned positive, rising 0.4 per cent.
Bullion prices GC-FT dropped with the August contract down $32.90 at $1,520.50 an ounce after rising for the previous seven sessions.
New York markets were mainly lower as data came out showing more Americans filing for jobless insurance last week.
The U.S. Labour Department said applications rose by 9,000 to a seasonally adjusted 429,000 last week. It was the second increase in three weeks and the biggest jump in a month.
But rising hopes that Greece can avoid a default left the Dow Jones industrials DJIA-I well off early lows, losing 59.67 points to 12,050 after earlier retreating 235 points.
The Nasdaq composite COMP-I index gained 17.56 points to 2,686.75 while the SP 500 SPX-I lost 3.64 points to 1,283.5.       www.bgocled.com

Control IC to buy teaching E

LED control IC is mainly applied in full-color gradient dimming control guardrail lamps, LED decorative lamps, landscape classes, and other full-color RGB light source lamp synchronized scanning, full-color color control. With the growing popularity of LED light source, more and more customers to the LED controller, the controller was no way to buy many customers, LED products on the market now mainstream attention to the questions as follows:A low-voltage high-power LED products controllerLow-voltage LED products are generally designed voltage 12V-36V, the number of each circuit LED in series 3-6, with the step-down current limiting resistor, each loop current 20mA or less. An LED products from more than one loop of LED components, the advantage of low pressure, simple structure, easy to design; disadvantage: when the current is very large product, you need to configure the low-voltage switching power supply. The shortcomings of the products, limited, low-voltage long distance transmission is impossible, are limited to the small volume products, such as sign language, and other small graphics.According to this feature, the controller design specifications: 12V selection 75A/30V MOS power of control, the output current of 8A / Road; 24-36V control for use 60A/50V MOS power, output current 5A / road. Users can select the controller according to the above specifications of large ones, can buy low transition series, the gradient can also buy low-Series controller. Note must be a common anode LED (+) pole connection method, controller Yin (-) pole, the controller does not include low-voltage power supply.
Second, the pressure controller type LED products
High voltage type LED product design AC / DC 220V voltage, the number of 36-48 each LED circuit in series, each loop current of 20mA or less, limiting in two ways, one is the current limiting resistor, power resistor in this way consumption of larger, it is recommended every 4 LED in series with a resistor 1/4W metal mold, evenly distributed heat, this connection is the most stable in the present. The other is limiting resistor and capacitor in series, this connection most of the voltage drop in the capacitor, resistor power consumption, can only be used in a stable long bright state, if the flash capacitor energy storage, but doubling the voltage, LED is easy to damage. Those who use the controller's LED current limiting resistor must be used way, LED general each loop one meter, power 5W, three-color power per meter 15W.Common gradient controller NE112K control DC 1200W, NE103D AC load 4500W DC load 1500W, if the lamp flashes on the use of multi-unit NE112K, if you only need to use the whole flash NE103D. If you use a gradient method, to pay attention to the load matching, neon and LED light-emitting properties of the distribution is not the same, then the same circuit can not mix different types of load.
Third, the low-voltage LED product serial controllerLow-voltage LED products is to control the serial controller features more than large ones, the use of serial signal transmission to achieve control, the control unit 512 generally requires only four control connections, serial LED in the LED light source controller board needs with a register, the controller can use models NE040S controller, the controller's maximum capacity of 4096KBit, if the load cell 512 can be the largest LED screen to achieve 8192.


 For more visit: www.bgocled.com

DC characteristics of LED's along the side and reversecharacteristics

DC characteristics of LED's along the side and reversecharacteristics

Semiconductor material has a very interesting feature is the so-called carrier; carrier is divided into two categories: one for theelectronics, with a negative charge; the other for holes, positively charged. LCD light-emitting principle is to use two kinds ofcarriers can be combined under certain conditions, the energy released in the form of photons release and light.

As a result, according to different materials, electron and holeenergy level occupied by different means that the relative electron and hole energy levels is to determine the height difference between the two carriers are issued with the level of energy, they can produce different energy photons, thereby to control thewavelength of light emitted by the LED, which is the spectral orcolor.

Most of the applications, LED all the way over to DC to make, it has the following features:

Cis-side features: When a positive DC voltage with sufficient time, LED current to rise rapidly, and this leads to a current is called"cis-side current," while the voltage across the LED is called"cis-side the voltage. "If the voltage range of peaks and valleysmeans that the quality of an exception, usually the shorter the wavelength of the LED the voltage will be higher.

Reverse side features: As the name suggests is to give LEDnegative voltage, also known as "drain voltage", in general,different LED materials will have their reasonable voltage, reversevoltage characteristics caused by bad because electrostaticdischarge, the this feature can also be used to assess the quality of the LED.


  For more visit: www.bgocled.com