Discussion: Circuit Scribe Update

I've decided to do a little update on our Kickstarter project. Remember when I first blogged about this pen a few weeks back, they only had $17,000? Well, they're rockin' over $500,000 now. It's crazy how fast this project grew. They reached their stretch goal of $250,000 in a matter of days! So, if you'd like to further fund ginormous bank account, click here. 

Gadgets: Gigs 2 Go

We have another Kickstarter project that needs your help. Gigs 2 Go is a pack of disposable USB drives that make sharing music, files, or anything you can think of easier with your friends, coworkers, or clients. It's actually a pretty neat idea. Instead of leaving your friend with your 64 GB thumb drive, you can give them one of these so you don't have to worry about them losing it. If you want to see more and possibly even fund this project, click here. 

Gadgets: T8X Spider

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This little dude is like the holy grail of remote controlled toys. Sure, it may cost $650 dollars for it and its controller, but it is so incredibly realistic in terms of movement. This is probably the most advanced piece of in the remote controlled toys category, simply because Chinese geniuses really put they're mind to it and came out with a motherboard that uses incredibly complex algorithms that allow it for its fluid, biological movement. In fact, its so cool that Adam Savage approves of it. Here's him playing with it and here's their website. 

Gadgets: Biopen

Have you ever broken a bone? If you have, I think we can agree that being stuck in a cast for six weeks is terrible, but what if there was a way out of that healing process? Modern technology is advancing so incredibly fast, it honestly renders me speechless. Researchers at the University of Wollongong, Australia, have created a pen that can heal broken bones much, much faster. All they do is apply the two separate kinds of "ink"that the pen contains. One cartridge of stem cells, and the other of a biodegradable UV-reactant protective gel that, when applied, hardens around the stem cells to allow it to heal undisturbed. This most likely means they'll have to cut you open, but no big deal! Because this stuff works on flesh too. Want more? Click here. 

Components: Transistors

Another component. Fun, right? Well this component is absolutely necessary to circuitry. Without it, almost every circuit out there would become useless if it suddenly disappeared. So, now that you're thinking, you're probably wondering what it does. Well, simple! Transistors are like an automated switch. It's almost like some of the switches we saw a few posts back, except you're essentially having a current of electricity to flip the switch rather than your finger, making it, in my opinion, one of these some of the most useful components out there.

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Transistors are actually categorized into two main categories: NPN and PNP. This stands for "negative positive negative" and PNP stands for "positive negative positive." They're basically opposites. Why is it named that? Well, look at the picture above. If you look at the bottom right picture, you'll see that rectangle is split into three portions: the collector, base, and emitter. The collector is like the first lead in a SPST switch, the base like the toggle, and the emitter like the other lead of the switch. If you were to use one for switching, you would basically have the collector hooked up to a positive source, the emitter to your ground, and the base to some sort of signal or pulse. When you apply power to the collector, practically no current flows through when the base doesn't receive a signal. When the base does receive a signal, the current flows from collector to emitter without a problem. This is where the difference between PNP and NPN comes in. The one above is an NPN transistor because positive voltage flows from collector to emitter and uses a positive voltage to trigger the base. The only difference in a PNP transistor is a polarity swap. Instead of positive voltage going in through the collector, it goes in through the emitter and grounds through the base.

So how do these work? No, there's no black magic going on here, it's actually pretty simple. The transistor is composed of three parts, collector base and emitter, that are sandwiched together. All three of these parts are made of silicon, which is a great semiconductor. What's a semiconductor? It's something that conducts electricity with an efficiency between that of an insulator and metal. But there is a difference between the three sections. In an NPN, the two pieces of bread, collector and emitter, are negatively doped. Yes, negatively doped, meaning the silicon is infused with an element with more electrons making it more negative, like phosphorus. Now the base is the opposite, it's positively doped, meaning it's infused with an element with one less valence electron than silicon, like the element boron.  Because the base is positively charged and the two other pieces are negatively charged, the positive base actually steals electrons from the negative sides to fill equalize everything out. The result of this is actually a little barrier-type deal that forms where the bread meets the meat where the base is actually slightly negative, repelling electrons attempting to flow from one end to the other. This barrier is very small and relatively weak, making it easy to break letting current flow through. How do we do this? This where the small positive current from the base comes in. If you look at the picture, you'll see a small plate hovering above the meat. When the plate is positively charged, it attracts the electrons from the collector and pulls it over to the meat. This process actually widdles the barrier down to practically nothing, giving the electrons a straight, undisturbed path from collector to emitter. It's amazing, right? 

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Now that we know how they work, let's apply them. One very basic NPN transistor that is used almost everywhere is the 2N2222 transistor. This one works like any other NPN transistor. There are a few rules we need to follow when using them. There needs to be a level of voltage applied to each piece of the sandwich relative to the other pins. This means that the collector needs to be the most positive, the emitter the least positive, and the base somewhere in between. So in this circuit, you have nine volts reduced by 560 ohms leading to the collector. Since the collector is reduced by more the 560 ohms for it to work, you'd have to use a resistor more resistive than 560. In this circuit, they actually replaced the resistor with your finger. Your finger is pretty stinking resistant than 560 ohms; depending on how far the two wires are separated. I clocked in about 800 ohms with a half inch of Dylan finger with my multimeter. Since the base has a weaker current being supplied to it, the base's current can flow through; resulting in an even weaker output from the emitter. Every thing checks out! So, when you touch the two wires to your finger, the current from the base can flow through, completing the circuit and in turn, illuminating the LED. 

I've only scraped the surface here. There are so many different types of transistors out there that it'll take you a week to learn the fundamentals to each one. There are MOSFETs, JFETs, IGBT, bipolar, junction, Darlington; it's nuts. Here's a Youtube video that will hopefully make more sense to you. I can only do so much here on a blog! The best way to learn, and it's the way I've learned, is online videos, books, and trial and error. Hopefully here pretty soon I'll provide a list of good sources and books you can look at.

Gadgets: Bitlock

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I have another gadget for you and it's geared towards the city people. Traffic stinks in the town so riding your bike may seem preferable than driving. Problem is, most bike locks are clanky, hard to lock and unlock; you get my point. Now, what if you could get a lock that would unlock automatically for you when you get within a certain distance from it? What if it's smooth and easy to work with? There are so many unique features implemented into this thing that's it's crazy, like GPS tracking, that they could even produce such a product. Check it out here at their website.

Gadgets: Atlas the Robot

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How would you feel about a six foot tall, 330 pound robot saving your life during a natural disaster? Let's say that a tsunami nails your town. Buildings are collapsed, homes full of water, unaccessible neighborhoods, you name it. Luckily, this robot, Atlas, is designed to save people during this kind of event. He can save you from rubble, drive utility vehicles, any action you would need during an event like this. This dude is like the new, jacked-up version of the Jaws of Life. Click here for more. 

Components: Switches

Okey dokey, we all know what a switch is; I mean we all have them in our house, right? You flick it when your lights are off and they suddenly turn on. Now what you may not know is how stinking complicated they can be and how stinking large the variety of switches is. I'm about to unleash a whole new world on you. 

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Look at that big 'ol switch. Looks simple, right? That's because it is. When it's off, you flip it to turn it on. Well, how does it work? MAGIC!! No... it too is pretty simple. There are two main parts to this rocker switch: the actuator and a set of contacts. The actuator... well, actuates and the two contacts sit next to each like a 2x4 that got a few inches cut out the middle. When the switch is "off", the contacts are "open", meaning they're not connected. When the switch is in the "on" position, the actuator connects the two contacts, "closing" them so a current is able to flow through from one to the other.

Now, it gets more complicated. There are many more kinds out there. What if you want to switch two currents at the same time? What if you want one position to close one connection and the other close another? Man that was a mouthful. I bet you had to read it more than once! Anyway... we have a system for this ordeal. A switch that would simply have an off position and one other that would close a connection would be a SPST switch, or a single pole, single throw switch.

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Take a look at this here knife switch. This is a SPST switch. Do you see the "knife?" Well, that's the pole. There's only one pole, or a single pole. This is where the SP in the abbreviation SPST comes from. There's also only one spot the knife slices into. This spot it called a throw; which explains where the ST comes from. Now... why is that connection called a throw? Well, technically in engineer language, when you flip a switch, you're supposed to say throw instead of switch. Why? No clue. Personally, I think it sounds goofy. "Honey, it's dark in here. Would you find throwing the light switch?" Funky. Anyway, that's why this type of switch is called a SPST switch.

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Now this here is a DPDT switch. You see these switches bolted to crazy scientist's lab walls. Now... why is it called a DPDT switch? Let's start with the poles. If you look very closely, you'll see that there are two knives! Bravo, you got it. What about the DT portion of the name? There are two sets of contacts, so it's a double throw. Simple enough! Now, what do you think it would look like if one knife went bye-bye? Well, it'd be a SPDT switch because there are two connections and one knife. What if it had four knives? Then it'd be a 4PDT switch.








Ok. Now, the thing is, you aren't limited to just one or two poles. If you need a switch that makes 1000 different connections, congrats. It's a 1000P whatever throw switch. You are however limited to the number of throws with this specific type of switch. Now there are switches out there that have multiple throws, like the rotary switch, but with the flip switches you'll probably only see a ST or DT switch. So since there are multiple different states each switch can be in, you know, on or off, how would we indicate that? Well, the only factor that affects the number of states is the throws. If you have a SPST switch, there's the off position and the on position so that leads it to be an ON-OFF switch. If you have a switch with two poles, it'd be an ON-ON position. I know I'm stating the obvious here, but you need to know this. Why? Well some DP switches will actually have a middle position in-between the two on positions called the OFF position. This sucker is a life saver because without it, a DP switch would always be on. Always, no matter what. When the switch is in the off position, no current can flow through, which is brilliant. So, a DP switch with an off position would be an ON-OFF-ON. There's an actual reason for this. Push button switches can be momentary or not and they specify this by using the on/off system. If a momentary button only turns on if you hold it down because if you release it, it turns back off. How would you specify the secondary position is monetary? OFF-(ON). The parenthesis tell you the on position is momentary. Man... aren't switches fun? I made all this sound much more complicated than it really is but once it clicks in your head, it really seems simple.

Now, if you'd like to see a nice, wide variety of switches and buttons out there, click here to check them out!

Gadgets: Amazon Prime Air

Now, you can't just go out and buy this thing like you can with most the other gadgets I've talked about here, but this still deserves some attention. How would you like to order something from Amazon and have it at your house in about a half hour? Yeah. Thirty minutes. So... how would they do it? Drones baby! A little drone will pick up your package from the warehouse and fly it to your house. Pretty cool, right? Click here for more. 

Gadgets: Super Bra

This one's for all you ladies out there. What we have here is exactly what it sounds like! No, they didn't make a bra that's as comfortable as Nike's Dri-Fit gym shorts (and my Lord those things are holy. Seriously, if you don't own a pair, go out and get one or ten; you'll thank me later) but they did completely geek-ify it. They implanted a chip and a sensor that records and guesses your emotions with 75% accuracy by picking up EKG activity (electronic pulses) near your heart. Are you stressed? The bra knows. You joy eating? The bra knows. Now you may be wondering... what's the practical purpose of this? Actually, I have no idea. Since it sends it's readings to a smartphone, maybe us men can use it to make you gals more predictable and easier to understand! *Wink* Here's the link!

Lessons: #4 Soldering

Ok. Lets say you wanted to take that LED circuit we "made" a while back in lesson 2 and make it into a permanent circuit. How would you go about doing that? You wouldn't super glue the leads to the wires and you sure wouldn't tape them together. So, how would you do it? 

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Here's the answer. It's soldering! (Yay..!) Anyways, it's essentially a metal super glue. Solder is a metal that melts at a relatively low temperature; about 360 degrees fahrenheit to be exact. When you want to connect two components together, you tie their leads together and heat them up to that temperature so the solder will melt and flow around the contact, then hardening to get a more-or-less permanent bond. The process is pretty simple, it takes a little practice, but once you do it a few times, simple soldering is a piece of cake. Let me take you through some of the basic steps. 

1. Plug in your soldering iron and let it set out for about five minutes; giving it time to heat up.

2. Tin your iron. You'll do this by taking a bit of solder and touching it to the tip of your iron. This'll help with the heat transfer. 

3. Twist the leads of your components together, preferably a couple times. This will allow the solder to flow in between the joints, giving you a really solid connection when it hardens.

4. If you're soldering some delicate components together, you'll want to put some heat sink by the components base so the heat from the iron won't burn it out. Heat sink is usually just a small copper clip you clip onto your component that will redirect the heat into the clip instead of allowing it to go directly into your component. 

5. Hold your iron against the soon-to-be connection for a few seconds.

6. With your iron still on the joint, take your solder and touch it to the joint. The solder should flow right into it. 

7. Pull iron away and there ya go! Don't touch it for a bit, it's most likely hotter than no other. 

For the more visual learners, here's a Youtube link for ya. 

Components: #2 The Symbols

Alright, so understanding the purpose and functions of electronic components is important, but being able to understand various schematics is just as important. You need to know what a schematic is saying so you can replicate it in the real world; this is how you learn. You learn by going along with trial and error.

Take a look at the chart to the left. Here are just some of the symbols used to represent components. There are resistors, capacitors, diodes, transistors, LEDs, switches, relays... you name it. Unfortunately, well, depending on how you look at it, there are a lot of symbols to memorize, but like I said, that can go either way because, sure there may be more symbols out there, but that also means more options when it comes to making your circuits. So personally, I see this as a great thing! I like to have a variety when it comes to designing instead of being restricted to a certain set of limitations. That's just sucky.

Well, anyway... you'll see these symbols everywhere. You even saw them back in lesson #3 with the simple LED circuit. You saw a battery, a resistor, a switch, and of course, the LED. So, yeah. That's all I got for ya. We'll definitely use this very soon when we look over and dissect more complicated circuits in the next lesson or so. Credit for the photo goes to Forest M. Mims III from his engineering mini notebooks.

Gadgets: Leap Motion

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Leap Motion. Something I thought I would only see in the future. Something you would see being used in the Enterprise or Tony Stark's house, not something you could get for $80 and plug into your Dell. Leap Motion sets out an invisible foot by foot by foot cube in the air that, incredibly accurately, scans your hand's every movement. You can interact with things on your computer screen by swiping thought the air, you can make a finger-gun and play first-person shooters, you can sculpt digital clay pots. This thing is so accurate that you can sign your name with your finger and it will look exactly how you wrote it. Exactly. Every inch and cranny my man, it's insane, and all for 80 bucks? When I was at Best Buy a few days ago I about picked one up! Here's their website, check it out

Discussion: Circuit Scribe

So my friends, I've got something for you, and quite frankly, I'm excited just sitting here typing this! This is such a cool, innovative idea that'll let you literally draw out your circuits and test them on paper you drew them on. Yep, you heard me (or more appropriately, "read me")! 

 

I draw out my circuits all the time. If I have an idea, I do draw it out! Then I have to find the free time to piece it together on my breadboard, which is just a solder-less test-board for circuits. Piecing together the components on that slap of plastic can be time consuming and sometimes frustrating! But man... the worst part is having to take it apart when I'm done with it having to completely re-construct it when I need it again! Getting the components out is no biggie, but having to arrange them all into the correct order and positions is just awful. That's why I love this pen so much. You could literally have a notebook full of schematics that already has the wires laid out along with spots for your components, then all you'd have to do is put the components in and shazam! You've got your circuit. So, how does it work? Simple. They made a water-based conductive ink and instantly dries on paper. Smart, right? It works just like a normal ballpoint pen too. This would be especially good for students taking electronic engineering classes because instead of having to draw out the circuit and having to build it to test it, you can just test it on your paper. Not only that, but it would allow hands on note-taking that will show you how the circuit is working. Isn't that awesome? Now, do you know what's even cooler? It was made by the University of Illinois. Yep, our university invented it! You can fund this awesome project here on Kickstarter; and please do! I did my share and put $35 towards it. It's actually crazy how fast they've gotten their funding. They're not even 24 hours from me posting this and they already have $50,000 with a goal of $85,000. Now, if you'd like to learn even more, click here to go to their website. Since they introduced this project yesterday, their website is pretty boring, but it's surely going to improve in the near future! 

Components: #1 Intro + Resistors

The electronic components. Your phone, computer, TV, lights, everything out there that feeds off of electricity wouldn't be here without them. Every one of them: resistors, capacitors, diodes, batteries, solenoids, transistors, wires, MOSFETs, gates, ICs, relays... the list goes on and on my friend. Each one of these little wonders has their own unique job, and when you combine these components correctly, you may just come out with something as useful and awesome as a computer. 

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Here are what some of the components look like in the real world. When you're designing a circuit, you don't just jump in and start soldering things together, you design it sort of like you would with a blueprint. Go to a piece of paper and draw it out! Then with a little math magic (or a computer program), you could see if it works. If you want to go onto making circuits, then you're going to need to know what each component does and how to draw it out. 

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The resistor. This component is probably one of the most used ones out there. Remember how back in lesson 2 we didn't want too much coming out of the spout? Reason is, if there was too little resistance, too much would come out and your cup would overflow, but if the resistance was too high and not enough water was coming out, your cup would sit there for days. Well this is why this component is so important. The units used for measuring resistance is in "ohms." Now, looking at the picture to the left, you may be wondering how you can tell how many ohms each resistor provides. Well that's easy. First one is 330, second 33k, 560, 150k and so on. Now, how can I tell? The colored bands that wrap around each one. Black = 0, Brown = 1, Red = 2, Orange = 3, Yellow = 4, Green = 5, Blue = 6, Purple = 7, Grey = 8, and White = 9. Now, if the resistor has three bands and one off to the side, the first two will tell you what the first two digits are and the third will tell you what the multiplier is ("a" and "b" times 10 ^ "x" power) So, if a resistor has, in this order, a red band, a purple band, and a yellow band, you know that the first two digits are 2 and 7 and the multiplier is 10 to the 4th power. Now for the math! 27 x 10^4 = 27k. That resistor is 27k ohms. Pretty easy, huh? It especially is once you have the color codes memorized like yours truly. Blue stands for 5, yellow for 4, grey for 8, black for 0. I am just that good. Now, I said earlier that there is usually 4 bands on there... we only talked about 3. So, what's that fourth band for? Not all resistors are perfect. Some have a plus or minus percentage from the stated value due to it being near impossible to make a component perfect. Now, the color codes are different for this band, but luckily, chances are, you won't need to learn them. The only two you'll need to know it Gold which is +-5% and Silver which is +-10%. So, if a resistor of 220 ohms has a silver band on it, it means the true resistance is somewhere between 198 - 242 ohms. If we have a 1k ohm resistor with a gold band, then the rating will be 950 - 1050 ohms. Easy enough, right? For additional info, click here.

Gadgets: Foldio

If you sell stuff on Ebay, this is for you. Foldio is an origami-type pop-up thing that gives you a really nice background for the things you're taking pictures of.  Once you put your item in the box and take your picture, it'll look like it's floating in mid air! So, this product isn't out yet but if you'd like to see it a reality, then back it on Kickstarter here!

Gadgets: The Kano Computer

This Kickstarter project is going places. I don't know if you've tried to learn programming by teaching yourself, but it is BEYOND difficult... well it was until someone had this idea. It's basically a tiny computer you get to build! You know what's better? The computer you build is full of games that'll teach you programming. The lessons are sorta like Luminosity, you learn without knowing it! Just take a look at it, and fund it if you'd like! Click here. 

Gadgets: Livescribe 3

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I'll admit it. I love taking notes on paper. I'd much rather right them out than use my fat thumbs to try and poke letters on my phone's touchscreen in a feeble attempt to type something down, only to lose the document into the depths of its memory card. Thank the Lord there's a solution for it!

Discussion: 3D Printers

This field is about to EXPLODE!! Seriously, explode like a bomb. It's going to be equivalent to like the smartphone. Why do I think this? Well, imagine being able to create almost anything you ever dreamt  in a matter of a few minutes. Want a new cutting board? Go print it. Oh no! Your phone case broke? Go print it. The handle on your toilet snapped off? Go print it. Seriously, anything you would ever need could be printed right in the comfort of your own home. 

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Here's one now. Look at its beauty! You can see that this one just finished printing a toy car. Just look at it for a minute. What do you think its made of? Well, there are actually a lot of different methods out there. They usually lay down successive layers of liquid resin or metal, powder, or sheet material successively so that that each layer will form a small bit of whatever you're printing. Now, what's really cool is how it knows what you want to print. You go into a computer program and design your object and simply upload it into the printer, and bam! You now have yourself whatever you want printed. 

These wonders aren't just restricted to solid plastic objects, they can actually go as far as to print food. Yes, food. You may not be able to print like a whole turkey yet, but something like chocolate? That's easy. Put some melted chocolate into the printer and have it print a bunny. Maybe in a few years you'll get your turkey, but what you can do so far is still pretty sweet. 

So, why hasn't the market exploded with these printers? Simple. There are key patents out there that restrict them from being produced cheaply, but there's some good news! Those patents will expire in 2014, so like I said earlier, they will EXPLODE!! So my suggestion? Go to the stock market and invest in major 3D printing companies before the turn of the year. Hopefully, you'll make some big dollars!

Gadgets: The Camera For Travel Enthusiasts.

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Are you a travel junkie? Then you may consider getting this panoramic awesomeness. This ball will help you get the shot of a lifetime, and all it needs is a few seconds of hang-time. Here's where you can read more.

Lessons: #3 Our Very First Circuit

Lesson three is upon us! Here today we are going to (kinda) make our own circuit. We know almost enough already to do so so why not? So... what kind of circuit? One that will light up an LED, or a light emitting diode. Now, before we can get started, we need to discuss something, and that'd be a component called a resistor.

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Remember from lesson 2 when there was the water tank analogy, and the width of the spout was the resistance? Well, sometimes you really need some resistance in a circuit for it to function properly. Imagine your spout was really, really wide and there was an enormous amount of volume traveling through it and you were trying to fill up a small cup. The cup would almost immediately fill up and start to overflow, spilling water everywhere. So, in other words, a complete catastrophe. Same concept goes for electricity. Imagine you're building an LED circuit. The LED is your cup, the battery is the tank and the resistance is your nozzle width. Now, you obviously need a certain resistance so your cup doesn't overflow too quickly and, well, one that's not too thin so the water doesn't slowly drip out like a faucet in an old building. You want a resistance that will fill your cup up right at a nice pace. Now, back to the circuit. You need a resistance that will keep your amps right in the LED's butter-zone. So, how do you get that resistance? Use a component called a resistor! A resistor is a component that will deliver a certain amount of ohms to your current so the amps are satisfactory. Now, how do you find out how many ohms you need? 10? 1,000? Simple. Do you remember Ohm's Law? You know your voltage because you have to know what kind of battery you're using, and you also know your amps because your LED will tell you how much you need. So, let's figure this out.

Let's say we have 2 AA batteries that gives out a total of 3VDC (volts direct current) and the LED, for our convenience, operates at 3VDC at 25mA (milli amps). So, we know our numbers, so all that's left to do is plug and chug! I = V/R plug our numbers into our equation: 0.025A = 3VDC/R. Once you do the math, you should come out with 120 as your answer. So, for your LED to opperate well, you'll need a 120 ohm resistor in your circuit!

For more awesomeness, head to lesson 4!

Lessons: #2 Circuitry Basics 2

So, besides AC, or alternating current, and DC, or direct current, there are other specifications that will help define the electricity your dealing with. What's the currents pressure? What's it's volume? Whatever circuit you're dealing with, you need to know these things.

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Voltage (volt) is current's pressure and amperage (amp) is the current's volume. Another important variable to know is how much resistance the current is encountering and we use "ohms" to represent that. Now, take a look at the diagram to the right. We have a tank full of water with a spout at the bottom. The difference between the two is the resistance, or "ohms," which is another very important factor. Now, the amount of water is the "voltage," the width of the nozzle is the resistance, and the "amps" is a result of the resistance. Now, you need to know that more resistance = less flow and this diagram illustrates that. The thinner the nozzle the more resistance there is and that reduces the volume of water allowed out, or amperage. There's a really simple equation out there to calculate this and that would be Ohm's law. I = V/R  where "I" is your amps, "V" is your current, and "R" is your resistance. This makes since because 1/1 = 1 and 1/2 = .5 proving the illustrations above are true.

Want more? Head on to lesson 3!

Gadgets: Your Own Robot Butler

  

How cool would it be to build a robot? To have your own personal remote controlled tank that could run over soda cans and stuff? Well, Makeblok made that a reality. All you need is a little software and electronic know-how and you can make whatever your nerdy heart desires with the completely customizable aluminum pieces you can put together like Legos to form your robot's body. Here's where you can get them.

Lessons: #1 Circuitry Super Basics

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Ok, so while we're on the topic of cool gadgets like projecting keyboards and remote controlled paper airplanes, why not talk about how they work? I bet you're curious as to how the guts of these contraptions make them do what they do, so... I'm going to teach you! But before you get to understanding something complex like a projector, we need to start with the basics.

Look at the picture to the right. Kind of obvious what's going on here, right? You have a battery that powers a bulb. Now, this picture isn't correct for a few reasons but I'll discuss those later.

There are two ends to the battery: the positive end and the negative end. When a circuit is formed, the electrons flow from positive end to the negative end; powering any components that come between them. Well, that's how we initially thought it flowed; but further study showed electrons flowed from negative to positive, but it was too difficult to change the math equations we had already formed to fix our mistake so we continue to think it flows the wrong way. So, any way, there are two more broader classifications of electric flow out there. There's AC voltage and DC voltage, or alternating current or direct current. There's basically only one difference and that's how they travel. Direct current is the kind of electricity you'd find pumping through your phone or flashlight. This electricity flows in one direction; kind of like water flowing through a pipe. Now, alternating current does something funky. Imagine you have that pipe of water, but instead of the water constantly flowing in one direction, it sloshes back in forth. It goes forward then back, forward then back. It still moves in a general direction, kind of like taking two steps forward and one step back. You'd find AC in your outlets.

Hopefully, you very vaguely know how electricity flows now. So, why do you think the diagram above is false? Think about it. That light bulb was probably made to be powered from an outlet, but it's hooked up to battery. What's the difference? Batteries supply DC and outlets supply AC! Plus, outlets supplly much much more power than a dinky little battery.

So, want more? Go on to lesson two!

Gadgets: Remote Controlled Paper Plane

How disappointed  were you when you threw a paper airplane, hoping to see it soar like an eagle but to really watch it painfully fly straight into the ground? Yeah, it sucks; it's all happened to us, but there's a really cool solution that Gajitz has come up with that will turn your airplane from a stinky ground-magnet into a remote controlled super-plane that can fly like a fighter jet. Here's where you can get one.

Gadgets: A Keyboard That's Better Than Yours

This seems to be something you would only see in Tony Stark's house, but since technology is growing like a fungus in an incubating room, it's now a reality.