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Building A Hardware Store Faraday Cage

Most Hackaday readers are no doubt familiar with the Faraday cage, at least in name, and nearly everyone owns one: if you've ever stood watching a bag of popcorn slowly revolve inside of a microwave, you'be seen Michael Faraday's 1836 invention in action. Yet despite being such a well known device, the average hacker still doesn't have one in their arsenal. But why?

It could be that there's a certain mystique about Faraday cages, an assumption that their construction requires techniques or materials outside the realm of the home hacker. While it's true that building a perfect Faraday cage for a given frequency involves math and careful attention to detail, putting together a simple model for general purpose use and experimentation turns out to be quick and easy.

As an exercise in minimalist hacking I recently built a basic Faraday cage out of materials sourced from Home Depot, and thought it would be interesting to not only describe its construction but give some ideas as to how one can put it to practical use in the home lab. While it's hardly a perfect specimen, it clearly works, and it didn't take anything that can't be sourced locally pretty much anywhere in the world.

Faraday Cage Design

At the most basic level, a Faraday cage is an enclosure made of a conductive material that blocks electromagnetic fields. In comparison to a Faraday shield, the cage variant is not a solid object, but rather a metallic mesh. Among other advantages, this allows observation of the subject inside of the cage. Put simply: if you simply want to protect a device from interference (or prevent it from causing interference) then it's enough to enclose it in a metal box; but if you want something that you can experiment with, you'll probably want a cage.

The trick is to make sure the holes in the cage material are smaller than the wavelength you wish to block. It's the same principle that allows you to use standard chicken wire as a RF reflector as long as you're working with relatively low frequencies. But as your target frequency increases the wavelength gets small enough that it can sneak through chicken wire, so you need to use something tighter. But how small is small enough?

To start, we need to find the wavelength for the frequency we want to block. This can be found by dividing the wave's speed in meters per second by its frequency in hertz. As we're dealing with a radio wave we know it will be traveling at the speed of light, and for the frequency let's say we want to block 2.4GHz. So the math will look like:

The rule of thumb for a Faraday cage is that the openings should be no larger than 1/10th of the wavelength, which in our case is 12.5 mm (approximately 1/2 inch). As luck would have it, steel "hardware cloth" with mesh sizes of 1/2″ and 1/4″ is widely available. On paper either should work, but I did end up going with the 1/4″ to be safe.

Construction

With the mesh in hand, the next step is to build some kind of frame for it. As it so happens, Home Depot has wooden crates in their storage section which are strong and relatively cheap. You could also construct a frame from pieces of wood or PVC pipe, which may end up being cheaper if you don't mind taking the time to build it.

I popped a couple of the slats out of one side of the crate so it would be easier to see inside, but beyond that, the construction simply consists of wrapping the crate with the hardware cloth. I did one long piece that started at the front and wrapped all the way to the back, and then two smaller pieces to "cap" the sides. In the end, it's not entirely unlike gift wrapping; if the gift wrap was metal and had a nasty tendency to cut you, anyway.

One thing to pay close attention to is where pieces of the mesh overlap. You want to maintain a good electrical connection and avoid any gaps, so you should overlap the pieces by at least a couple of inches to be safe. I attached the hardware cloth to the crate with a power stapler, so I also made sure to drive a few extra staples through the areas where the mesh overlapped to ensure they were held together tightly.

Testing

As a simple test, I set my phone up on the bench running the signal strength function of the "WiFi Analyzer" application for Android, with an Access Point that's one floor above selected as the target. In the two pictures below, the only thing that has changed from one shot to the other is placing the DIY Faraday cage over the phone.

As you can see, the phone had a signal strength of approximately -55dBm originally, and it dropped down to nearly -80dBm when inside the cage. Weaker Wi-Fi networks were rendered undetectable when the phone was inside the cage, and there was a clearly detrimental effect on the phone's LTE reception.

Flawed Design

I should say, before the commenters below get a chance to do it for me, that this is admittedly not a very good Faraday cage. For one, it's not fully enclosed. Since there's no bottom signals are still able to enter from below, greatly reducing its effectiveness. The steel mesh is also not an ideal conductor, and copper would likely work better. But finding a local source of tightly wound copper mesh proved tricky.

There's also some debate about whether a Faraday cage must be grounded or not. For what it's worth, during my testing there was no observable change in performance when the cage was grounded. Though it's possible a more conventional Faraday cage may perform differently.

Having said that, I still feel this design blocks RF enough to be useful. It will never completely isolate the device inside from electromagnetic interference (or vice versa), but it attenuates signals significantly enough to be clearly observable. That was the extent of my ambition to begin with, so I'm happy with the results.

Possible Applications

Imagine you are developing or testing a remotely controlled device, and want to see how it behaves when signal strength is poor. Tossing the cage over it would allow you to induce a drop in signal strength instantaneously. Or perhaps you're observing the RF emissions of a device, but want to cut-down on superfluous background noise. Putting the piece of gear under test and your SDR hardware inside the cage would be an easy way to study it in a less "noisy" environment.

Those are just two possibilities. This demonstration shows there's really no good reason not to have a simple RF blocking device at your disposal. It's cheap, it works, and it can be your next weekend project. What you do with it is up to you, just make sure you drop us a line when you figure it out. What would/do you use a Faraday cage for?

Trump Migrant Separation Policy: Children 'in Cages' In Texas

The authorities released this image of illegal migrants inside a large cage - reporters said they saw unaccompanied children in similar conditions

Reporters and Democratic lawmakers have been allowed inside a detention centre that lies at the heart of a growing storm over a new US policy separating migrant children from their parents.

Authorities did not allow photos or videos to be taken inside the centre, but US Customs and Border Protection later released several images. Former First Lady Laura Bush has compared it to the internment camps used for Japanese-Americans during World War Two. A Democratic congressman who visited the site said it was "nothing short of a prison".

The Texas facility is known as Ursula, though immigrants are reportedly calling it La Perrera - dog kennel in Spanish - in reference to the cages used to hold children and adults who have ended up there after crossing the border from Mexico illegally.

"One cage had 20 children inside. Scattered about are bottles of water, bags of chips [crisps] and large foil sheets intended to serve as blankets," the Associated Press reports.

This image from the US Customs and Border Protection shows the foil blankets given to children

Democratic Senator Jeff Merkley led the team of lawmakers to the site in the town of McAllen on Sunday.

Speaking to CNN after the visit to Ursula, he said: "In wire-mesh, chain linked cages that are about 30x30 [feet], a lot of young folks put into them.

"I must say though, far fewer than I was here two weeks ago. I was told that buses full (of children) were taken away before I arrived.

"That was one of my concerns, that essentially, when you have to give lengthy notice, you end up a little bit of a show rather than seeing what's really going on in these centres."

Maryland Senator Chris Van Hollen and Vermont Congressman Peter Welch expressed shock and anger over the conditions they saw:

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Inside Ursula, more than 1,100 illegal immigrants are waiting to be processed. They have been separated into three wings: unaccompanied children, lone adults and parents with their children. Officials said nearly 200 of those being held there were unaccompanied minors and another 500 were parents with their children.

The Los Angeles Times, which also sent a team there, described the 72,000 sq ft facility as "clean and spare, with bare concrete floors".

A patrol agent currently in charge of the site, John Lopez, told the paper the 42 portable toilets on site are cleaned three times a day. There are three paramedics, two medical members of staff and 310 employees - but no mental health staff, or training, the paper notes. The main lights in the building remain on at all times.

Read more on US migrant family separations:

Nearly 60 miles away, in the town of Brownsville, some 1,500 boys are being housed inside a building that was once a Walmart superstore. The boys, aged 10 to 17, were all caught illegally crossing the border. It is America's largest facility for such minors, and numbers have increased in the past month by several hundred.

Senator Merkley's Facebook Live on 4 June showing security officials denying him entry to that site - known as Casa Padre - led to questions about conditions there. Last week, news organisations were given a tour.

Zero-tolerance: The US policy dividing families and opinion

No cages were mentioned, but the accommodation was likened to dorm rooms inside a giant warehouse. To accommodate for the growing numbers since the new "zero-tolerance" policy went into force, cots have been added to sleeping areas in the Casa Padre.

Long-term trauma?

"Those kids inside who have been separated from their parents are already being traumatised," Senator Merkley warned. "It doesn't matter whether the floor is swept and the bed-sheets tucked in tight."

Officials say they are trying to keep siblings together and not separate children under four or younger from their parents.

The head of the Tahirih Justice Centre in Houston said she had seen cases where parents had not been told ahead of time that their child was being taken away, and instead were told by immigration officers that their child required a bath, only to not be returned.

"I was talking to one mother, and she said, "Don't take my child away," and the child started screaming and vomiting and crying hysterically, and she asked the officers, "Can I at least have five minutes to console her?" They said no," Ms Chandler told the magazine.

Authorities say they do not separate parents with children under five

A rights worker who visited the Ursula facility at the weekend told the Associated Press she had spoken to a 16-year-old girl who was left in charge of an unaccompanied toddler for three days and tasked with changing the child's nappies.

"She had to teach other kids in the cell to change her diaper," Michelle Brane, from the Women's Refugee Commission, said. The girl - who was four years old - was later reunited with her aunt, but the process took time because she did not speak Spanish but a language indigenous to Guatemala, the agency reports.

"She was so traumatised that she wasn't talking," Ms Brane said, describing the girl. "She was just curled up in a little ball."

She is not alone in voicing concerns over the long-term effects of separating adults and their children.

Separately, authorities have announced plans to erect tent cities that will hold hundreds more children in the Texas desert where temperatures regularly reach 40C (105F).

Local lawmaker Jose Rodriguez described the plan as "totally inhumane" and "outrageous", adding: "It should be condemned by anyone who has a moral sense of responsibility."

What is the policy in other countries?

Trump's blame game on separating families

How Melania compares to other first ladies

Sessions defends separating child migrants

Why Spanish speakers in US are under fire

Trump sets targets on immigration cases

What Is Nicolas Cage's Net Worth?

Nicolas Cage is an American actor who has a net worth of $40 million. Nicolas Cage's net worth at one time was much higher, easily over $100 million, after earning at least $200 million from movie salaries alone between 1980 and roughly 2010. Nick's profligate spending is somewhat infamous today. Despite being one of the highest-paid stars in Hollywood, Cage got himself into some serious financial straits resulting from both his failure to pay his taxes and some bad real estate investments that left Cage in a position where he had to sell not only his Ferrari Enzo but other prized possessions as well. These possessions most famously included his copy of "Action Comics #1" (one of the most valuable comic books in existence), which he sold at auction for a record-breaking $2.16 million. We detail his years-long, impressively wild spending spree later in this article.

Early Life

Nicolas Cage was born Nicolas Kim Coppola on January 7, 1964, in Long Beach, California. His father, August Coppola, was a professor of literature, and his mother, Joy Vogelsang, was a dancer and choreographer. August passed away from a heart attack in 2009. Cage has two brothers and attended Beverly Hills High School and UCLA's School of Theatre. Through his father, Cage is the nephew of director Francis Ford Coppola and actress Talia Shire and the cousin of directors Sofia Coppola and Roman Coppola and actor Jason Schwartzman. To avoid the appearance of nepotism, Cage changed his last name, which was inspired by the Marvel Comics superhero Luke Cage.

Tim Mosenfelder/Getty Images

Acting Career

Cage landed his first film role in 1982's "Fast Times at Ridgemont High" and, from that time, he worked steadily throughout the '80s and early '90s in such popular films as "Valley Girl," "Raising Arizona," "Peggy Sue Got Married," "Honeymoon in Vegas," "Face/Off," "Con Air," "Gone in Sixty Seconds," "The Rock," and "The Family Man," just to name a few of his more than 70 film credits to date. His second-highest-grossing film to date was 2004's "National Treasure." Despite his success in many of these big-budget action films, most of his lower-profile movies have been box office letdowns compared to his action/adventure mainstream flicks, which tend to be enormous successes. His 2006 remake of "Wicker Man" failed to make back its $40 million budget and opened to overwhelmingly negative reviews.

In 2007, Cage was spotted at a wrestling show researching for the lead role of Darren Aronofsky's "The Wrestler." However, he later dropped out of the running for the part. Mickey Rourke went on to receive an Academy Award nomination for his performance in the lead role. In 2009, Cage starred in "Bad Lieutenant: Port of Call New Orleans," directed by Werner Herzog. The film received universally positive reviews, and Cage was lauded for his lead role. He hit box office success in 2012 with "Ghost Rider: Spirit of Vengeance," which grossed $585 million. His next film, "Joe," was a box office flop. In 2018, Nicolas starred in the Elijah Wood-produced film "Mandy," an action thriller that received much critical praise. Wood intended to drum up Oscar support for Cage, but ultimately, the film was disqualified for a late-in-the-year release. Nicolas signed up to play the lead role in Richard Stanley's 2018 film "Color Out of Space," which was Stanley's first feature film since 1996.

Cage went on to star in 2021's Pig, 2022's The Unbearable Weight of Massive Talent, and 2023's Renfield. Also in 2023, he donned the cape of Superman in a cameo in "The Flash" as an alternate version of the superhero.

Financial Problems and Recovery

Between 1996 and 2011 alone, Nick earned more than $150 million from acting salaries. He earned $16 million for "Snake Eyes," $20 million for "Gone in Sixty Seconds," $20 million for "Windtalkers," and $20 million for "National Treasure," just to name a few. Not surprisingly, as his income went up, so did his spending habits. Actually, to be fair, as his income increased, Nick's spending habits SKYROCKETED. Between 2000 and 2007, Nick went on a spending spree that would make the Sultan of Brunei blush. His purchases included 15 personal homes (including TWO castles), a $7 million private island in the Bahamas, four luxury yachts, a fleet of exotic cars, a $30 million private jet, dozens of pieces of art, jewels, and a 67 million-year-old dinosaur skull.

In 2009, the IRS filed a federal tax lien on a property Cage owned in New Orleans. It was alleged that he had failed to pay over $6.2 million in federal income taxes. Nicolas subsequently filed a $20 million lawsuit against his business manager, accusing him of negligence and fraud. By 2022, Cage confirmed he had finally paid off his debts and intended to be more selective with film roles after accepting anything and everything in order to build up the money needed.

Other Ventures

Cage made his directorial debut with 2002's "Sonny." He has produced "Shadow of the Vampire" and "The Dresden Files."

Nicolas has done voice work for "Teen Titans Go! To the Movies," as well as "Spider-Man: Into the Spider-Verse." He was the narrator of the 2019 film "Love, Antosha," a documentary made by Viktor and Irina Yelchin about their late son Anton Yelchin.

An avid comic book fan, in 2002, Cage auctioned a collection of 400 vintage comics for over $1.6 million. He created a comic book with his son Weston called "Voodoo Child" in 2007. Nicolas collects works by underground comic artist Robert Williams.

Cage made his video game debut in July 2023 as himself in "Dead by Daylight."

(Photo by Jason Merritt/Getty Images)

Accolades

Nicolas Cage won the Academy Award for Best Actor for his starring role in the film "Leaving Las Vegas" in 1996. He also won a Golden Globe for the role. He was nominated for an Academy Award for his portrayal of screenwriter Charlie Kaufman in 2002's "Adaptation." In addition, he has been nominated for Screen Actors Guild Awards, BAFTAs, and more.

Cage has also been honored with the Toronto Film Critics Association Award for Best Actor for "Adaptation." For his work in "Color Out of Space" (2018), Nicolas was awarded the Creative Coalition Spotlight Initiative Award at the Toronto International Film Festival. Cage was given a star on the Hollywood Walk of Fame in 1998. He was presented with an honorary doctorate in fine arts by California State University in 2001 and spoke at the graduation ceremony.

Sascha Steinbach/Getty Images

Philanthropy

Cage is a very generous Hollywood star. He donated $2 million to Amnesty International for rehabilitation shelters and medical and mental care for children across the world who are forced to fight in conflicts. He donated $1 million to victims in the wake of Hurricane Katrina. He supports ArtWorks, which raises awareness of fundamental rights at work. Cage was awarded the Humanitarian Award from the United Nations for his charitable acts.

Personal Life

Cage dated actress Christina Fulton for several years, and the two had a son, Weston (b. 1990.) He has been married five times, first to actress Patricia Arquette from 1995 to 2001. Nicolas and Lisa Marie Presley were married on August 10, 2002, and divorced 107 days later. Cage married Alice Kim in California in July 2004. They had a son together, Kal-El, in 2005. They divorced in late 2016. In March 2019, Nicolas tied the knot yet again with Erika Koike, but they filed for an annulment just four days later. In June 2019, their divorce was finalized. In February 2021, Cage married Riko Shibata. The couple had a daughter, August, in September 2022.

Real Estate

In 2006, Nick paid $8.5 million for a 14,000-square-foot home in Las Vegas. After briefly trying to sell the home for a bit under $10 million, Nick lost the home to foreclosure. In 2021, Cage paid $2.85 million for a home in Las Vegas.

In August 2024, Nick paid $10.5 million for a home in Malibu. The 4,000-square-foot mansion sits directly on the beach. There are four bedrooms and six bathrooms spread over four levels, with floor-to-ceiling windows in most rooms and the best appliances available. Nick got the property for a relative bargain. It was originally listed in June 2022 for $18 million. It was then offered as a rental for as much as $50,000 per month before Nick scooped it up for $10.5 million.

All net worths are calculated using data drawn from public sources. When provided, we also incorporate private tips and feedback received from the celebrities or their representatives. While we work diligently to ensure that our numbers are as accurate as possible, unless otherwise indicated they are only estimates. We welcome all corrections and feedback using the button below.

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