Farewell
Sadly, this will be my last article for Kibbles and Bytes. I’m going to be moving on from Small Dog to the next chapter of my life. I’ve really enjoyed writing articles almost every week and hearing from readers who learned something new or just wanted to tell me more about the topic I wrote about. I feel like I often learn more new things when writing. Usually I start off with a topic in mind, maybe something that I thought about in the week prior, and then research it in more detail. I’ve certainly covered a wide range of topics from gamma radiation to air conditioning to electrical safety basics. For this last article, I thought I’d share a bit about how I’ve picked up so much of this stuff and despite not having much formal training.
The only formal course I took on electronics was an in-development course in college. It was a brand new instructor and a brand new course the college was offering that year. I struggled tremendously in it. It was heavily math and theory-focused and my calculus background has always been pretty weak. I somehow managed to eke out a B average when all was said and done. I think if the course had included more hands-on learning, I would’ve done better. My skills have always been in putting theory into practice rather than just focusing on the theory alone.
I tend to be the kind of person who will decide to build something, and then do a ton of research until I understand what is going on. I remember when I built my solar power station, I did a lot of research to understand how to size wires for loads. You wouldn’t think something like that would be complicated, but actually, there’s a lot of theory behind it. What kind of amperage is involved? What will the voltage be? How long are the wires going to be? There are plenty of resources out there on the internet to help you on your way to learning about these things. I’m a firm believer that anyone with the desire can understand how all of this stuff works.
With electricity, there are always safety concerns. If you’re not confident about something, it’s ok to admit it. Remember that if the resistance is right, and there’s enough charge behind it, virtually any voltage can be lethal. Under most normal conditions, voltages below 48V are fairly safe. If you recall, my very first articles here about electricity basics focused on the safety factor and what was and wasn’t dangerous. If you’re looking to get involved in a project, 12 and 24 volt systems are generally pretty safe (shorts can still cause fires though). They can be a great way to work on gaining a better understanding of how electricity works. They also translate to useful projects. Most cars, for example, have 12 volt electrical systems, so if you’re comfortable working with that, there are lots of things you might be able to do.
Finally, you can always just read about the history of inventions and developments in the world of electromagnetism. Amps, volts, ohms…all of these terms are named after people. Reading about how they discovered what they did can really help to shed light on why we do things a certain way now, or how certain modern devices came to be. It can be incredibly fascinating to learn about the processes and experiments early scientists used to discover the fundamentals of electricity and it’s a great way to get yourself into the same mindset of learning.
Electromagnetism, at least the fundamentals of it, are what an old professor of mine would call “pure truth.” He was a professor of mathematics and computer science and he always told us that the things he was teaching us were pure truth. These things were true from billions of years before we were born, and they’d be true billions of years into the future and beyond. I always liked that. My hope in writing all the articles I’ve written is that some of you might have become more interested in some of those pure truths. Take care, and always keep learning.
Like a Regular Wave, Only Smaller
In my last article about lasers, a reader pointed out that in the history of the laser started off as something called a MASER. These devices were identical in functionality to a laser, except the beam was composed of microwave radiation, rather than visible light energy. In researching for my article, I had actually come across this fact, and I thought I mentioned it, but in re-reading the article, it looks like it slipped through the edits.
Obviously it’s easier to conceptualize lasers you can see. A MASER would be invisible since we can’t see microwave radiation. While the MASER didn’t really proliferate in the same way that lasers have, microwave radiation is one of the many things that makes our modern world work the way it does. To start off, let’s go to the obvious place, your microwave oven. Every single microwave oven in the world uses microwaves to heat food, but how does it work? First, we have to define what microwaves are.
Microwaves are electromagnetic radiation (yup, that same ol’ spectrum). They are defined as having wavelengths between one meter and one millimeter and frequencies between 300MHz and 300GHz respectively. Microwave radiation at about 2.45GHz has a special property though. When it passes through dielectric molecules, like water, it causes them to rotate. This rotation is the absorption of the microwave energy by the molecules. If you remember back to an article I did on cooling and temperature, the heat we see in the molecules is the result of them now moving. So the microwave oven isn’t heating your food, it’s heating any water or moisture present in the food. You can actually see the wavelength of your microwave by removing any turntable and placing a plate of shredded cheese inside. Turn the microwave on for approximately 30 seconds and take the cheese plate out. You’ll notice that there are rows of melted and unmelted cheese. The space between the melted rows is the approximate wavelength of the microwave.
Heating food isn’t the only use of microwaves though. Microwaves are the primary radio waves used for all modern communication. L band microwaves, from 1-2GHz are used for GPS, GSM mobile phones and amateur radio. S band microwave, from 2-4GHz are used for weather radar, microwave ovens, other mobile phones, WiFi, Bluetooth, and more GPS. The automotive radar I wrote about a few weeks ago is also a microwave. Some automakers will even call it “millimeter wave radar”. These microwaves are in the Q band ranging from 33-50GHz. Microwaves, unlike lower frequency radio waves, operate by line of sight and as such they are excellent for point-to-point communications.
I wonder if anyone caught something in that last paragraph. “Hadley, are you saying that the same band used for microwave ovens is used for cell phones?!?!” Yes, it’s true. Many mobile phones operate in the same frequency as microwave ovens. This is partially what caused a lot of concern when cell phones first started to proliferate. Is there a risk? Technically speaking, yes, but the risk is so incredibly minute, it would take decades of talking on the phone with it right to your ear before your ??chance?? of experiencing negative effects even rose a little bit. The reason for this is power. You may know how much power your microwave oven is rated for. Many are in the 1200 watt range. That’s 1.2 kilowatts of power. That’s ??a lot?? of power. That’s more power than a hair dryer might use, and the only way for most of us to get that power is to plug into the grid. A tiny cell phone battery is not capable of producing even a fraction of that power, and devices like WiFi transmitters are regulated to only transmit a certain amount of power.
Finally, why do we even call it radiation? Microwaves can’t cause chemical changes by ionization so they aren’t radioactive like plutonium is radioactive. This is one of the times we use “radiation” to mean energy radiating from a source. Technically you could call the light from a flashlight “light radiation”. The radiation itself is non-ionizing and therefore is not dangerous. The only danger from microwaves is if they are backed by sufficient power. Then your body could experience dielectric heating, just like in a microwave oven.
Hopefully this was a helpful discussion of what microwaves are and what they aren’t, and maybe I’ve removed some of the mystery of certain technologies that use them.
Apple Pencil
I am by no means an artist nor someone who has drawn anything beyond your standard High School art class. However something drew my attention the Apple Pencil, call it intrigue or even memorization of the new slick addition to the Apple line up I could not keep from considering why it was so endearing. […]
Avoid Phishing
Unlike the band (depending on who you ask, I suppose) to get ‘phished’ is not as groovy, wavy, or as psychedelic as their malicious digital counterpart.
We’ve all no doubt heard of the blowback and headaches that notorious phishing scams can cause, but how can you stay alert and protected when you cross paths with a potential scam?
I’m sure, right now, in your Spam inbox, you may find a number of emails from a sender masquerading as Apple, Microsoft, Google, Amazon, etc… asking you to “verify” certain aspects of your personal information i.e. credit card number, address, phone number, and in some cases even your Social Security number. I’ve dealt with a few of these cases personally, where the victim, unfortunately, thought these requests were legitimate.
Some things you can make yourself aware of if you feel a possible phishing email has pushed its way past your spam filter:
Note the subject line of the email. How’s the grammar? Does it sound fishy (forgive the pun) if you say it aloud to yourself? For example, Apple will never let even the slightest grammatical/syntax error go unnoticed, so if you receive an email from “Apple” and it reads like the first draft of a fifth grader’s procedural essay, delete it.
What’s the point of the email? Scammers are getting craftier by the day as cyber security measures are getting better and better at weeding out the malicious parties trying to swipe your personal info, so it’s unlikely that they’ll come right out the gate asking for your credit card number. Instead, they may try to get you to follow a link to their page to “verify” your personal info. Let’s just say, for the sake of this example, that you follow the link. Keep in mind, if it really is an email sent from Apple, the web address won’t look like this: http://appleid.apple.com.apple.givemeyourmoneyplease.4573949034.ithinkimsoclever.apple.com One thing to note here if you do click on their given link, Apple will never just use an ‘http’ address. All Apple websites are prefixed with ‘https’, with the ‘s’ meaning that a security certificate is in use to encrypt the communications between your device and the Apple web server.
Above all else, use your better judgment. If you have a sneaking suspicion that the email you’ve received isn’t genuine, call the company. If your account is really about to be deactivated, or your subscription is truly about to run out, a customer support representative of the company will certainly tell you. And please, don’t use the number listed in the email.
Technology Brings Us Together
A few weeks ago Small Dog sent me to Key West to help with the Small Dog team in the southern most point. While I was there I met this wonderful Chilean. One problem though is that we do not speak the same language. She was raised speaking Spanish, English for me. Thanks to our quick thinking we were able to communicate via translators built into a few different apps. She was using an iPhone 6 with the Whatsapp app. I was using an iPhone 5s with google translate, and with a lot of patience, we were able to hold a conversation strictly relying on our iPhones.
After I left Key West and went back to Vermont and her to Chile, we kept in contact via translators over Facebook. Until I realized that Skype had a translator built into the app, One problem it is Windows only! (Boo, Skype, Boo!). Lucky for me I already had the best windows laptop you can buy…a MacBook Pro!
So I partitioned my drive and now Running Windows 7 and OS X, which lasted about a week before going back to just OS X. Now the setup I use is Skype running on MacOS 10.12 with google translate.
The cool thing about Google Translate is that it has a speak option. So you type into one box and in the other box it would translate to Spanish, then just click on the sound button and google will speak in the language you translated to with a cool robot voice. The only problem that I have found with Google Translate is that they are not good with slang. I learned I use a lot of slang.
Reflecting back on this whole scenario it amazes me that we are in a time of such great tech(slang), and we do not use it to its full potential.
The cool, breezy evenings have set in and we’re starting to feel the first wave of Autumn here in Vermont. It is a bittersweet feeling, as always. I hate to see summer go by so quickly. As I said in our last edition, we’re in the midst of our busy back-to-school rush, which affects every department in different ways.
Going into the fall, we’re all gearing up to take tons of photos, especially here in Vermont. While I’m stocking up on color film and developing chemicals, I’m also looking into a better video rig. One of my coworkers has the latest GoPro Hero5, and I must say, the HD recording at 120fps is quite impressive. For the past couple of years, I’ve shot with a Canon 70D, which is well regarded for its video recording capabilities. This system is especially handy for filmmaking, as you can attach a variety of lenses to the body and achieve almost any cinematic look you desire. I’ve found for action video, this camera falls short for a few reasons. First of all, a larger camera body usually means less stability in the image. GoPros are so lightweight, you tend to have an easier time keeping things steady. In addition, recording 4K video gives you the resolution flexibility needed to apply heavy image stabilization in post-processing stages.
When I purchased the 70D, I never expected an action camera at half the price would surpass it in terms of video capacity and ruggedness. I should add, the 70D still has a superior image sensor in so many ways I won’t get into here, but if you’re looking to shoot action without the larger camera body getting in the way of your participation in said action, I think a GoPro is a worthwhile purchase. I’m especially fascinated by the extended range of FPS (frames per second) options going all the way up to 240. If you have a minute search for 240FPS GoPro footage on YouTube. Yes, your iPhone can now handle super slow motion at the same capacity, but I’d rather not take my iPhone out water skiing, skateboarding, or strapped to a dog’s head, for example.
Speaking of strapping to a dog’s head, we have a ton of GoPro mounting accessories at the South Burlington store, including the Karma Grip, which stabilizes even the most rocky footage, using an electronic gimbal. Very cool! If you’d like to hear more about these products, come see us at the store. If you happen to see Erich or Riley, make sure to ask them about their GoPro experience.
Have fun with your last couple weeks of summer, we hope to see you soon!
Patrick McCormack
“patrickm@smalldog.com”:mailto:patrickm@smalldog.com
How to Avoid Phish
Unlike the band (depending on who you ask, I suppose) to get ‘phished’ is not as groovy, wavy, or as psychedelic as their malicious digital counterpart. We’ve all no doubt heard of the blowback and headaches that notorious phishing scams can cause, but how can you stay alert and protected when you cross paths with […]
Set Phasers to Stun
I received a very good question from a reader about my article last week. The question was about interference between these radar systems on a crowded highway. I couldn’t easily find a good answer about this online, but my suspicion about this is that these systems function in a way similar to consumer-grade wifi transmitters. A full apartment complex might have a dozen or more wifi transmitters on top of each other spitting out signals that overlap and potentially interfere. This situation would be similar to lots of cars packed together on a highway. Wifi transmitters are designed with this possibility in mind. They use different transmission “channels”, basically just different frequency groups, to keep their own traffic under control and optimized. A transmitter will do this automatically by design. I’m almost positive radar systems in cars work the same way. Since they are radio frequency-based, they too can operate on discrete channels and switch to new channels if one has too much interference. However, one thing I did see a lot about was that these radar systems do mess with consumer-grade radar detectors pretty badly. So much so that detector manufacturers are starting to have to design their devices more intelligently.
Onto my topic for this week: lasers! Believe it or not, when the first lasers were invented in the 1960s, scientists called them “a solution in search of a problem.” It wasn’t apparent at that time how much use lasers could be, but today we rely on them from things as simple as barcode scanning at the grocery store to the fibre connections that form the backbone of the entire internet. Lasers are pretty complex pieces of technology and they involve some electrochemistry too (not my strong suit) but I’ll do my best to explain them for you here.
First of all, the word laser, like radar, is an acronym that stands for “light amplification by stimulated emission of radiation.” Would you like fries with that? The acronym is descriptive, but is complicated. At the heart, a laser has some kind of gain medium which can be energized somehow as well as some kind of construction that can provide optical feedback. The amplification part comes in when we start with the gain medium. In order for it to amplify light, we need to give it something to start with. Either energy (in the form of electricity) or light from some other source. This process of supplying energy to the gain medium is called pumping. Lasers can be pumped with many things including flash lamps, electricity or another laser.
A simple laser could be described as the following. Imagine a cylinder composed of the material to be pumped. On each end of the cylinder is a mirror facing the cylinder. When the gain medium material is pumped, it gives off photons in an amplified state which bounce back and forth between the mirrors, passing through the gain medium and being amplified more each time. Now imagine if one of the mirrors was translucent allowing some light to escape. We’d have a laser!
What is the gain medium composed of? In most industrial or scientific lasers, the gain medium is often some kind of gas, like helium, helium-neon, or carbon dioxide. If the gain medium is a solid, we call these solid state lasers. In these lasers, the gain medium consists of a glass or crystalline rod that is “doped” with ions in a process similar to “doping” silicon for use in photovoltaics. Finally there are semiconductor lasers. These lasers, while technically solid state, are not generally referred to as such and are most common in consumer grade devices. They are composed of diodes that are electrically pumped and function most similarly to our basic example above.
As they are most common in our daily lives, I’ll explain a bit more about semiconductor lasers. They can be made to emit laser radiation at wavelengths from 375nm to 3500nm. Why are so many of these lasers red though? Most laser pointers are red for example, as are most barcode scanners. The reason is because laser diodes are cheaply available in those wavelengths. To achieve shorter wavelengths, more sophisticated techniques need to be used. I have a green laser pointer at home that I got in 2006 for about $75 online. Little did I know at the time, but green lasers such as that one only became widely available to consumers in the early 2000s. Green semiconductor lasers are most often a type of diode-pumped, solid-state, frequency-doubled laser. The green light is generated via a two step process that starts with a lower energy laser diode in the infrared spectrum. This light is used to pump a—brace yourself—-yttrium orthovanadate crystal doped with neodymium. That gain medium is then where the green laser light comes from. I think laser scientists just want to obfuscate their devices with wild names.
I have to stop there because even my head is spinning a bit. Hopefully this was an ok explanation of these interesting and useful devices.
