Faraday Cage
By Timothy J. Gawne
I WAS IN LINE AT THE LOCAL Starbucks waiting to get a cup of coffee. I’d been waiting a long time—the lady four people ahead of me wanted a multicultural decafe triple latte pistachio almond blend frappe (or something like that—I never could get into anything more than just coffee) and it was taking awhile.
That was when the man in the tinfoil hat came to stand in line behind me. Now I was tempted to leave, but I had been waiting a long time and I wanted my coffee. I resolved to avoid eye contact and hoped that he would leave me alone.
Even with my back turned to him I could detect a jittery, nervous energy about the man, as well as an aroma suggesting that he had not showered in quite a few days.
“You’re wondering about my hat,” said the man addressing the back of my head. I said nothing, but he was insistent. “It’s to stop them from controlling my thoughts with radio waves.”
He moved to my side so that I really couldn’t avoid looking at him. He was a white male, scrawny, wearing frayed blue jeans, black tennis shoes, and a surprisingly pristine Wisconsin Dairy Farmers’ Association T-shirt. And he had a shiny aluminum foil hat that he had formed to cover his head from just above his eyes, going over his ears, and then down to the back of his neck.
“You mean the CIA?” I asked.
I immediately regretted my error in responding to him. “No, not the CIA!” he said angrily. “The NSA! Everyone knows it’s the NSA that controls people’s thoughts with radio waves! Are you making fun of me?”
The man’s eyes were bulging and, while I knew that, statistically, crazy people are safer than the so-called sane, he was definitely creeping me out. But at this point if I just left he would probably follow me ...
“And why is the NSA trying to control your thoughts?” I asked, for want of any other idea of what to say.
“Because I’m so smart,” said the man. “They are afraid of me. So they have to control my thoughts! So I try to block them with this metal hat.”
“But that might not work,” I said. “A Faraday cage often has to be grounded to provide efficient shielding.”
He looked at me suspiciously. “Are you threatening to put me in a cage with a wild Faraday? Are you one of them?”
I raised my hands in a gesture of peace. “No, no, that’s not it at all. A Faraday cage is named after the famous physicist Michael Faraday. He showed that a conductive metal box would shield anything inside it from external electrical interference. But, depending on the details of the geometry and the frequencies, the box often has to be electrically connected to a ground to function.”
The line moved forwards another step. There was one person left in front of me, but he was ordering an espresso a la nuit with flaming brandy, and the barista was having trouble locating the igniter for the flaming brandy.
“So what is a ground?” asked the man.
“Well, a good source would be a metal cold water pipe. You just take a copper wire, run it from the Faraday cage, and connect it to the pipe. Remember, the pipe has to be metal.”
“Well, duh, the pipe has to be metal. I’m not stupid you know. But why cold water?”
“Good question,” I said. “It’s because hot water pipes usually come out of hot water heaters, and that can break the electrical connection to the true earth ground.”
I had finally made it to the front of the line, and ordered my standard small black American coffee. The barista acted confused, as if he had never heard of such a thing. He might have been put off by my use of the word “small.”
“Ah, that makes sense,” said the man. He looked around the Starbucks, and as luck would have it there were two shiny metal copper pipes on the far wall. He went over to them, and felt them. He tapped on the upper one. “This is the cold water pipe. But how am I going to connect it to my hat?”
“You could just touch your head to the pipe,” I suggested.
The man started to get angry again. “I’d look pretty stupid with my head pushed up against a water pipe!” he shouted. “How do I connect to the pipe!”
I looked around—what could be used as a wire here? Starbucks stores are not generally equipped with jumper cables or patch cords. But then I had an idea.
“You can use the metal plugs at the ends of a USB cable,” I said. “Ideally you want one without a ferrite bead—that’s the big lump you see on some of them. Only push hard because it can be difficult to get a decent electrical contact just by touching two pieces of metal together. Here, I have a spare, it’s yours.”
I pulled an old blue-plastic USB cable out of my laptop case, and gave it to the man. He touched one end to his metal hat, and the other to the cold water pipe. At first nothing happened, and I was getting ready to make a getaway, when the man began to calm down. His tremor stopped, his eyes regained focus, and his breathing slowed. He looked at me with a steady and intelligent gaze.
“That’s ... interesting.” The man said. “Thank you. You have been very helpful.”
I mumbled a brief “you’re welcome,” picked up my coffee, and made good my escape.
***
The next day I showed up at the same Starbucks. There were an even dozen young men and women sitting at tables working intently on their laptops. They were all dressed casually but stylishly, and I noticed that they were all wearing tinfoil hats. These were each connected to the cold water pipe at the far wall, but this time they were using long extension cords so that they could get up and move about and use the restrooms.
One of the men saw me and waved. “Oh, hello, it’s you again!” he said. “I wanted to thank you for your help! Let me buy you a coffee. And you can have your USB cable back.”
It took me a while to realize that this was the same man that I had encountered the other day. Other than the tinfoil hat, he appeared a completely different person: well groomed, well dressed, confident.
One of the young women tapped a few keys on her laptop. “OK, got it,” she said. “We’re done here.”
“About bloody time,” said another one of the young men. As one, they all removed their tinfoil hats, and calmly began to pack up their laptops and leave.
The man that I had met the other day took off his hat, wadded it up into a ball, and made a perfect bounce shot off the wall and into the trash receptacle.
“Umm, aren’t you worried about the NSA controlling your thoughts?” I asked.
The man smiled at me. “The NSA? Nah, that was just a front. Let’s call the responsible parties them. But they will no longer be a problem. For anyone. Ever. Now let me buy you that coffee. And you will be rewarded. But even so, if you ever need help, find me. I still owe you a debt, and I won’t forget.”
“But if I need help, how will I find you?”
The man smiled again. “No worries. If you need help, I’ll know, and I’ll make sure that you do find me. Now, a regular small American coffee, right?”
***
Later that night after I arrived home, I found a package on my front doorstop. I opened it and unpacked ten bright blue USB Cables. They looked pretty good quality.
When I checked my bank account, I saw that ten million dollars had been deposited into my savings. And not just that—the taxes had been pre-paid in full, so it was clear. Additionally, my student loans had been zeroed out, and my mortgage paid off. I wasn’t quite sure that I should believe my good fortune. I resolved to do nothing and see if it was still there in the morning.
I sat down and turned on the television and watched the news. The president announced that he was ending his policy of dropping bombs on random middle-eastern countries because he was bored with it and, frankly, it seemed kind of pointless. Then the head of the Federal Reserve announced that, in future, fiscal policy would be changed to support productive investments in real enterprises and not be a rigged casino. An aged Dick Cheney, interviewed at his nursing home, publicly apologized for being a prick. During the commercial break, a spokesperson for Starbucks announced that in the future they would only be serving coffee in small, medium and large sizes, and that anyone with the temerity to order a multicultural decafe triple latte pistachio almond blend frappe would be ritually executed by Tibetan monks.
And my parents used to think that I was crazy to become an electrical
engineer. 
Timothy J. Gawne is an MIT trained engineer with a Ph.D. in physiology. He is the author of the popular “Chronicles of Old Guy” book series. He has also contributed to numerous scientific papers in the fields of neuroscience and psychiatry.
