Electromagnetic Compatibility (EMC) · 1:27pm Nov 15th, 2015
A mysterious hooded figure is seen on campus holding an electronic device with antenna making strange noises. What is she up to? A night-time statue cleaner? A magical portal maintenance maintainer? A gardener?
Here’s another theory. But to explain this, I must first introduce you to the dark and scary world of EMC – three letters which strike terror into the heart of experimental scientists, radio amateurs, and consumer electronics company executives.
Electromagnetic Compatibility – or the lack of it – is about electronic gadgets interfering with each other. A taxi radio setting off a burglar alarm, your mobile phone creating breakthrough on your audio system. You turn on your laptop on the plane, and it interferes with the navigation system and sends it off course. This is serious. If you think I’m exaggerating read some of the stories on this site.
All electronic equipment will radiate some radio or other electromagnetic waves. This is what happens when you push electrons around, and modern electronics pushes them faster and harder than ever before. High speed gadgets are a ubiquitous part of our world. The only reason why our electronic society can function in this world of electromagnetic chaos is that there are strict regulations governing the EMC requirements of all electronic devices.
Case 1. Imagine this scenario:
You are a top executive in a big global consumer-electronics company, paid an excessive salary to ensure your business continues to make a profit. You are almost ready to release the new all-singing, dancing, magic-working Twilight Sparkle pony games console, which your market research practically guarantees will be a mega hit with gamers.
Except you hear a rumour that your competitor is about to release the new ultra-awesome Rainbow Dash pony games console. Which will be faster, with more colours, 20% better specifications, and can fly! You face the prospect of being swept aside by the competition and your only hope to recover the enormous amount of money you have invested in developing this product is to get your console to market first.
So you beg, bribe and bully your technical staff to finish the design NOW! Despite their pleas that they need more time to properly test the prototype. You put together your marketing strategy, and send out all the press releases. You’re all set to go…
Then you receive a phone call. It’s failed the EMC test! Those @#%*!! regulators have said it emits too much electromagnetic noise and cannot be authorised for sale in the United States, European Union or Japan. You have the hottest new console ever—but you can’t sell it to your biggest markets. If it’s any consolation you can maybe still sell it in the Federated States of Micronesia, where the standards are said to be not so strictly enforced.
You shout at the lawyers, but they just shake their heads. You go and scream at the engineers and tell them to fix it. Engineer A says you need to shield it in a solid aluminium box, but that won’t work as marketing says it has to be shaped like a pony. Engineer B wants to redesign the whole thing, but it has to be on sale, like, yesterday!
So you shout and scream some more, pay all your technical staff overtime, hire some EMC consultants at an exorbitant rate, and eventually they find a way to reroute a few circuit board tracks, replace the bad components, and work in a bit of black magic, so they can reduce the emissions levels to just below the legal limit. You breathe a huge sigh of relief. The marketing team swing into action. And a few weeks later you have good laugh when you hear that the release of the Rainbow Dash console has had to be postponed due to EMC issues.
Now let’s get back to the mysterious hooded figure snooping around campus.
Case 2. Picture this:
You are a top experimental scientist and have just finished setting up your latest project in your basement laboratory, which will measure the hyperfine splitting of certain atomic energy levels to an unprecedented precision. Or something else equally cool. This has taken months of work constructing the apparatus. You need to cool your sample to milli-kelvin temperatures, isolate it from mechanical vibrations, and manipulate it in controlled electric and magnetic fields. You have finally got everything up and running. You turn it on, and instead of the beautiful signal you were waiting for, you just see some hideous noise on your display!
You double check your equipment. Everything is in order. It’s something coming from outside. A quick analysis identifies emissions at many different frequencies. Is someone else doing something dodgy? Maybe a power distributer unit has malfunctioned. Or the telecom firm that installed your network connection took a few short-cuts when setting it up. Is some student using an illegal games console, bought on ebay, imported from Micronesia? Has some computer user installed some dubious new boards in their desktop and left the side cover off because they think it looks cools, completely oblivious to the fact that they are filling their room with RF noise and slowing down their network speed?
Or probably the most likely reason, is that the scientist in the lab next door is running their own experiment to study the behaviour of protons in intense RF fields, which has the side effect of generating an excess amount of electromagnetic noise.
You need to figure out what’s going on. But you need to be discrete. If you tell anyone about the problem, then the guilty party will just keep quiet. They need to get the results to finish their next research paper, and they don’t want anyone telling them they can’t run their experiment. They don’t want to stop playing with that cool new games console either.
So you need to gather the evidence before confronting anyone. You get out you portable spectrum analyser – a nifty little gadget which can scan the radio spectrum from kHz to GHz and identify the frequencies of any anomalous emissions. Pull up your hood, and walk around campus when you hope no one is looking, and try to pin down the source…
sounds cool
Certainly a reasonable hypothesis given what an on-site observer would have to work with. And thanks for introducing me to a whole new world of technical horror stories.
The really cool thing is that nowadays, running around waving antennae at things is neither difficult nor expensive. With a $20 digital TV receiver and some free software running on your laptop, you too can enter the wonderful world of radio hacking.
Maybe the student next door has an unshielded computer running at an obsolete frequency thats beating with someone elses experiment to cause the noise, and its that machine because he needs the ports to bit bang randomly at high megahertz rates at femtosecond jitter rates. While multitasking. While battery powered.
Hmm, proton resonance in RF fields. Apply a helmholtz magnetic field, and a static HT electric field, and you have the Confusor.
Now if only we can get them off the DCT and onto the full FFT, preferably with large sample depths, and hardware multistage full width fractal analysis.
I really need to find those articles on massively parrallel stochastic oscilators. white noise is random, but carefully manipulated phases can get you zero sum And Delta energy spikes. Fully deterministic harmonic chaotic energy.
Easiest way to see if something is fractal? Fractal is self similar, it looks the same at all scales, hence if you take the fourier transform, the signal should have harmonics, for the occurances at scales, and phase shifts for the various rotations, amplitude for scaling. Im wondering if quaternion FFT will give shear and stretch transforms as other phase shifts on other axis?
At least she can use better gear than I had with just a ZX Spectrum in the 80s when trying to write a story about analysing alien signals using a genetic evolution algorithm.
Speaking from personal experience?
I'm sort of glad I'm a biologist, I've just got to worry about my samples eating or breeding with each other.
I'm convinced that was actually a Stantz-Spengler-pattern PKE-meter.
3543844
Yes. Although none of my cases turned out to be very interesting - just things like old fluorescent lights. But you hear some really crazy stories in this business.
Nematodes? Or something cute and furry? I don't have to deal with that problem.
3543900
It's been a while, but blood feeding flies, mostly tsetse and mosquitoes.
The eating each other had mostly been bacteria and the like, feeding the mosquitos was easy given I'm full of blood. As for breeding well they were supposed to be radiation sterilised but one or two tend to avoid it.
Very intriguing idea.
Psh. That's a PKE Meter if I ever saw one.
Awesome!
Quick question: What's an RF field?
I've always assumed that magic interferes with electronics, at least to some degree. Most consumer goods will survive an encounter with magic, although they probably won't work properly until the magic field goes away.
If nothing else, it makes a human showing off his new iPhone 19 to a pony that much less impressive.
3544478
Radio Frequency. Sorry - jargon
If you've ever tried to record audio, you know EM noise and improper grounding is a serious problem.
During my freshman year of college, there was a big dispute between the school and city over a proposal to install a huge cell tower on a hill overlooking the school. Long story short, the city won and our precious experiments were blasted into electromagnetic oblivion… or so the story goes.
During my final year, my RF class modeled the behavior of the new tower. We concluded that the tower barely affected the school at all, since it was designed to concentrate its signal in a completely different direction.
I thought that was a given?
3544654 No problem, I enjoy learning technical jargon.
Thanks for the reply.
One of the things I liked about this movie was that it showed that Equestrian magic doesn't supersede the laws of physics, it has to interact with them in a meaningful way, for example by magical energy releasing some form of radiation that can be detected by technological devices. Heck, the whole reason Twilight is able to "steal" magic is that she has built some sort of exotic energy-absorbing properties and can release them as well.
I'd love to see future work done with Twilight's technology, I wonder if it could mimic specific "spells" if Sunset helped break them down into complex patterns of energy bursts?
3544655
Ah yes - the wonderful sound of 50Hz hum.
3544706
Interesting. I always guessed that the RF intensity from such towers was less than that from all the student phones used on campus. But as they don't publish the details, it's hard to be sure.
3544626 3545163
It seems when you mix electronics and magic, anything can happen. You build a simple device with a well defined function. Expose it to magic and it takes on a life of its own. You try to do a proper scientific investigation and... look at what happened to Sunset Shimmer.
3545474 That's because its two teenagers doing raw experimentation, there are always bizarre unexplained phenomena with brand new fields of science. Eventually working together I could see Sunset and Twilight figuring out the patterns and being able to predict and anticipate the effects magic will have on technology and vice versa.
3544626 That's a good point, and probably explains why Equestria doesn't have so much as a telegraph system yet. I suspect Twilight's locket device was radiation-hardened to stand up to all that magic.