Home
In this issue

Jonathan Tobin: Defending the Right to a Jewish State

Heather Hale: Compliment your kids without giving them big heads

Megan Shauri: 10 ways you are ruining your own happiness

Carolyn Bigda: 8 Best Dividend Stocks for 2015

Kiplinger's Personal Finance editors: 7 Things You Didn't Know About Paying Off Student Loans

Samantha Olson: The Crucial Mistake 55% Of Parents Are Making At Their Baby's Bedtime

Densie Well, Ph.D., R.D. Open your eyes to yellow vegetables

The Kosher Gourmet by Megan Gordon With its colorful cache of purples and oranges and reds, COLLARD GREEN SLAW is a marvelous mood booster --- not to mention just downright delish
April 18, 2014

Rabbi Yonason Goldson: Clarifying one of the greatest philosophical conundrums in theology

Caroline B. Glick: The disappearance of US will

Megan Wallgren: 10 things I've learned from my teenagers

Lizette Borreli: Green Tea Boosts Brain Power, May Help Treat Dementia

John Ericson: Trying hard to be 'positive' but never succeeding? Blame Your Brain

The Kosher Gourmet by Julie Rothman Almondy, flourless torta del re (Italian king's cake), has royal roots, is simple to make, . . . but devour it because it's simply delicious

April 14, 2014

Rabbi Dr Naftali Brawer: Passover frees us from the tyranny of time

Greg Crosby: Passing Over Religion

Eric Schulzke: First degree: How America really recovered from a murder epidemic

Georgia Lee: When love is not enough: Teaching your kids about the realities of adult relationships

Cameron Huddleston: Freebies for Your Lawn and Garden

Gordon Pape: How you can tell if your financial adviser is setting you up for potential ruin

Dana Dovey: Up to 500,000 people die each year from hepatitis C-related liver disease. New Treatment Has Over 90% Success Rate

Justin Caba: Eating Watermelon Can Help Control High Blood Pressure

The Kosher Gourmet by Joshua E. London and Lou Marmon Don't dare pass over these Pesach picks for Manischewitz!

April 11, 2014

Rabbi Hillel Goldberg: Silence is much more than golden

Caroline B. Glick: Forgetting freedom at Passover

Susan Swann: How to value a child for who he is, not just what he does

Cameron Huddleston: 7 Financial Tasks You Should Tackle Right Now

Sandra Block and Lisa Gerstner: How to Profit From Your Passion

Susan Scutti: A Simple Blood Test Might Soon Diagnose Cancer

Chris Weller: Have A Slow Metabolism? Let Science Speed It Up For You

The Kosher Gourmet by Diane Rossen Worthington Whitefish Terrine: A French take on gefilte fish

April 9, 2014

Jonathan Tobin: Why Did Kerry Lie About Israeli Blame?

Samuel G. Freedman: A resolution 70 years later for a father's unsettling legacy of ashes from Dachau

Jessica Ivins: A resolution 70 years later for a father's unsettling legacy of ashes from Dachau

Kim Giles: Asking for help is not weakness

Kathy Kristof and Barbara Hoch Marcus: 7 Great Growth Israeli Stocks

Matthew Mientka: How Beans, Peas, And Chickpeas Cleanse Bad Cholesterol and Lowers Risk of Heart Disease

Sabrina Bachai: 5 At-Home Treatments For Headaches

The Kosher Gourmet by Daniel Neman Have yourself a matzo ball: The secrets bubby never told you and recipes she could have never imagined

April 8, 2014

Lori Nawyn: At Your Wit's End and Back: Finding Peace

Susan B. Garland and Rachel L. Sheedy: Strategies Married Couples Can Use to Boost Benefits

David Muhlbaum: Smart Tax Deductions Non-Itemizers Can Claim

Jill Weisenberger, M.S., R.D.N., C.D.E : Before You Lose Your Mental Edge

Dana Dovey: Coffee Drinkers Rejoice! Your Cup Of Joe Can Prevent Death From Liver Disease

Chris Weller: Electric 'Thinking Cap' Puts Your Brain Power Into High Gear

The Kosher Gourmet by Marlene Parrish A gift of hazelnuts keeps giving --- for a variety of nutty recipes: Entree, side, soup, dessert

April 4, 2014

Rabbi David Gutterman: The Word for Nothing Means Everything

Charles Krauthammer: Kerry's folly, Chapter 3

Amy Peterson: A life of love: How to build lasting relationships with your children

John Ericson: Older Women: Save Your Heart, Prevent Stroke Don't Drink Diet

John Ericson: Why 50 million Americans will still have spring allergies after taking meds

Cameron Huddleston: Best and Worst Buys of April 2014

Stacy Rapacon: Great Mutual Funds for Young Investors

Sarah Boesveld: Teacher keeps promise to mail thousands of former students letters written by their past selves

The Kosher Gourmet by Sharon Thompson Anyone can make a salad, you say. But can they make a great salad? (SECRETS, TESTED TECHNIQUES + 4 RECIPES, INCLUDING DRESSINGS)

April 2, 2014

Paul Greenberg: Death and joy in the spring

Dan Barry: Should South Carolina Jews be forced to maintain this chimney built by Germans serving the Nazis?

Mayra Bitsko: Save me! An alien took over my child's personality

Frank Clayton: Get happy: 20 scientifically proven happiness activities

Susan Scutti: It's Genetic! Obesity and the 'Carb Breakdown' Gene

Lecia Bushak: Why Hand Sanitizer May Actually Harm Your Health

Stacy Rapacon: Great Funds You Can Own for $500 or Less

Cameron Huddleston: 7 Ways to Save on Home Decor

The Kosher Gourmet by Steve Petusevsky Exploring ingredients as edible-stuffed containers (TWO RECIPES + TIPS & TECHINQUES)

Jewish World Review

How giant TV screens work

By Marshall Brain

Printer Friendly Version
Email this article

http://www.JewishWorldReview.com | (MCT) Think about the biggest TV screen you have ever seen. For example, the biggest TV in the world is more than 100 feet wide and 55 feet tall.

A gigantic screen like this is made of millions of tiny light bulbs called LEDs. But there are also hundreds of computers at work, and enough electricity to power a small town. Let's explore the biggest sign in Times Square in New York City - the NASDAQ Marketsite Tower sign - to find out how these megascreens work.

Let's start with the smallest part of the sign - a single Light Emitting Diode, or LED. An LED is a tiny colored light bulb. You see these little lights everywhere - for example, your DVD player might have a red LED that tells you whether or not it is on. LEDs have three big advantages when it comes to making a gigantic TV screen. First they are bright. Second, they are efficient, meaning that they turn most of the electricity they receive into light. Third, they last a long time. A typical LED might last 100,000 hours before it burns out.

On any large LED screen, you use clusters of LEDs to make one pixel. For example, a small sign uses one red LED, a green LED and a blue LED to make one pixel. By changing the brightness of the three LEDs, you can create any color in the rainbow. Turn all three LEDs off and you have black. Turn them all on at full brightness and you have white. And you can create any color in between.

In a big sign like the NASDAQ Marketsite Tower, you need even more LEDs in a pixel because the sign is so large. This sign uses two red LEDS, three blue LEDs and three green LEDs to make a single pixel. Since the sign has 1,800 by 1,200 pixels, that means that there are about 17 million LEDs in the sign!

These LEDs are wired onto boards called tiles. A tile has 256 pixels, arranged in a 16 x 16 grid, with 8 LEDs per pixel. A tile also has its own computer to control the LEDs on the tile. The NASDAQ sign has 9,000 of these tiles, each about a foot square.


Donate to JWR


The tile needs data to tell it how to light up its 256 pixels. This data comes from a main control computer that knows how the whole screen should look. The data for the tile contains an intensity level for the red, green and blue LEDs for each of the pixels. In other words, 30 times each second, all 256 pixels on the tile need to get intensity information. The computer on the tile decodes this information and drives transistors that send electricity to the LEDs. The tiles all chain together, one to the next, and pass the data from the main computer from tile to tile.

The other thing a tile needs is power. Each tile uses about 60 watts when all the LEDs are lit at full intensity. The power comes from a set of 700 power supplies that are housed behind the sign. If you multiply 9,000 tiles by 60 watts, you can see that this sign needs 540,000 watts - enough to power several hundred houses.

The problem is, all those tiles and power supplies generate a LOT of heat. To handle all this heat, 12 large air-conditioning compressors chill a glycol solution that circulates behind the sign. The air conditioners can use about as much power as the sign itself.

If those air conditioners were ever to fail while the sign is running, it would be a big problem, especially if someone was working on the catwalks behind the sign. It's estimated that it would only take a few minutes for the heat to build to 200 degrees or more behind the sign. Anyone working in the tower would bake to death.

Who would think that it takes so much technology to show a picture on a screen? These giant signs are a lot more complicated than they look, and that is what makes them so expensive. It cost tens of millions of dollars to put up the NASDAQ sign. Just the electricity for the sign costs more than $1,000 per day.

Every weekday JewishWorldReview.com publishes what many in the media and Washington consider "must-reading". Sign up for the daily JWR update. It's free. Just click here.

Comment by clicking here.



Previously:


How foreclosure works
How Air Force One works
How wildfire fighting works
How vitamins work
How ejection seats work
How reattaching limbs works
How hot air balloons work
How paparazzi work
How counterfeiting works
How CDs work
How the Edsel worked
How Stinger missiles work
How hybrid cars work
How sharks work
How mosquitoes work
How diesel engines work
How water towers work
How the Dawn mission works
How Kassam rockets work
How the North American Eagle works
Why aren't we flying to work?
How tofu and soy milk work
How Colony Collapse Disorder works
How airbags work
How the U.S. income tax works
How gum works
How caffeine works
How Daylight Saving Time works
How a cruise missile works
How snow making works

© 2007, How Stuff Works Inc. Distributed by McClatchy-Tribune Information Services.

Columnists

Toons

Lifestyles