We’re very proud of Make: Electronics, the beginner’s guide to electronics written by MAKE contributing editor Charles Platt. It has consistently been an O’Reilly bestseller and has already been through several printings. It’s a hit! It seems to fulfill the exact purpose we set for it, which was to basically be a truly accessible, plain-spoken, visual beginner’s guide to electronics for the early hours of the 21st century. If you’re new to electronics and interested in diving right in, experimenting with components, and then learning about the theories behind them (a process Charles dubbed “learning by discovery”), you really should check out this book.
To give you a chance to do just that, we’re running a giveaway, thanks to our pals in the Maker Shed. To be eligible, all you have to do is tell us in comments what’s the biggest nagging question you have about electronics. Are you wondering in which direction electrons actually flow? What all of those little letters after “V” (voltage) are for on a circuit diagram? What the third power post on a common breadboard is for? What flux is all about? No question is too basic. And after the drawing, we’ll try and answer as many of these questions as we can. If you don’t have any questions, you can help (and be eligible for the drawing) by answering questions or sharing some interesting information about electronics that beginners might benefit from.
We’ll be giving away five (5) copies of the book. Deadline for comment entries is 11:59pm PST, Wednesday, Jan 26th. Winners will be announced on Thursday morning. Good luck.
More:
- Make: Electronics – Interview with Charles Platt & Gareth Branwyn
- James Floyd Kelly completes Make: Electronics
- Make: Electronics and the 555 man
In the Maker Shed:
Make: Electronics
Want to learn the fundamentals of electronics in a fun and experiential way? Start working on some excellent projects as soon as you crack open this unique, hands-on book. Build the circuits first, then learn the theory behind them! With Make: Electronics, you’ll learn all of the basic components and important principles through a series of “learn by discovery” experiments. And you don’t need to know a thing about electricity to get started.
As DIP packages become less and less common, how are we going to respond? Is PCB etching and surface mount soldering just going to become another requirement of electronics, or will breakout boards for every chip become a competitive enough secondary market to keep us going?
Why is Electroboards the only company I can find selling good general-purpose SMD breakout boards?
I get the relationship between voltage, current, and resistance, but I don’t know how to do anything more interesting with it than light up a bulb or make a motor spin. Even then, I’m not confident I won’t set fire to anything, and while I’m not afraid to tinker (and have actually fixed some electronic via basic troubleshooting), complex circuits make me feel like I’m missing out on the secret handshake.
I guess I know how a capacitor works… I just don’t know why you would want one. If this book would lift the shroud of confusion and get me on track to building and modding, I’d love a copy!
There is a bit of a secret handshake. Electronics is a vast field that can appear quite overwhelming. But ohm’s law is part of the secret, so you are off to a great start. Further more, much design is individual circuits chained together. Then tweak your circuit empirically, and how it all works together becomes harder to see.
So how do you know if you are going to start a fire or not? Ohm’s law says the voltage equals the current multiplied by the resistance. So with any two of these, you can calculate the third. Power equals current times voltage. By lowering resistance, for the same voltage, you have increased the current. So you have increased the power. Put a wire with very little resistance across a battery, then the wire and battery will get hot. The wire might melt. (try a 9 volt battery on steel wool) But if the battery gets too hot, it might pop, exposing you to the nasty chemicals inside or worse. So be careful when you play with fire.
For your next question, there are many uses for a capacitor. A capacitor is made up of two conductive parts that are not touching. If you put a voltage across a capacitor, positive and negative charge will build up on it’s two sides, with charge on one side attracted to the opposite charge on the other side. If you remove the external voltage, the capacitor will still have the charge you gave it. That charge across a capacitor creates a voltage of it’s own. The voltage is the same as that external voltage that we just removed. So a capacitor stores voltage. If you put a resistor across the capacitor the charge will flow through the resistor to the opposite charge on the other side of the capacitor. The larger the capacitor, the more charge you can bleed off this way before you run out of charge, and thus reduce the voltage to zero.
Continuing, using ohm’s law we can calculate the initial current through the resistor. That current through the resistor creates a voltage across it equal to what the capacitor holds. That voltage holds back more charge from flowing. So the resistor limits the speed of the capacitor discharging. The smaller the resistor, the faster the charge discharges. A new law to know is the RC time constant. The resistance multiplied by the capacitance equals the time it takes for the voltage to drop 63%. It will take the same amount of time to drop the next 63%, and so on. This also works going the other way, and charging a capacitor through a resistor. It will take one RC time constant to charge 63%.
So a capacitor tries to maintain it’s voltage. The larger the capacitance, the larger the time constant, and the slower the change in voltage. So one use of a capacitor is to reduce fluctuations in the voltage in part of a circuit. So you can use a capacitor to quiet the noise on a power supply. The noise is the fluctuations you don’t want. Similarly, if you put capacitors across the power pins of IC’s, you can create more stable power for all your chips.
There is much more, but this is getting long, and I am typing on my iPad.
As others have pointed out, capacitors store energy in electric fields, and inductors store energy in magnetic fields. But it’s also useful to think of them as resistors — but very odd resistors.
Capacitors are like resistors that decrease in value with frequency. For “DC” (non-changing) voltages, they have infinite resistance; for very high frequencies, they have very low resistance. Thus if one were to replace the lower resistor in a resistor divider with a capacitor, one would get a divider network in which the lower resistor looked very big for low frequencies and very small for high frequencies — this is a low-pass filter. You will often see them used this way in power supplies.
Inductors are like resistors that _increase_ in value with frequency. For “DC” voltages, they have almost no resistance; for very high frequencies, they have a very high resistance. If you substitute an inductor for the _upper_ resistor in a divider network, you _also_ get a low-pass filter — and again, you will often see them used this way in power supplies.
Why must they be color coded?
I’m colorblind, and would prefer to just read the numbers on them.
If there is a place I can purchase Numbered resistors, I’d greatly appreciate it.
A magnifying glass is much better than asking a friend to help me with a hobby they have no interest in, or using my Color Guessing program on my phone, which has had limited success (though not completely useless).
You may look into surface mount resistors. Although there are the obvious connection differences, which can be overcome by being creative, many have the value written right on them, especially the larger sizes. Look into 0805 and 1206 sizes. Anything smaller becomes much more difficult to handle.
My color vision is fine, but I seldom bother decoding the color bars on resistors. You should have a digital multimeter handy anytime you’re working on electronics, so just set it to ohms and measure the resistor you’re holding. The only times I’ve bothered with the color codes are when I’m teaching the concept, or when I’m sorting a large number of resistors from a mixed package. Otherwise, it’s much quicker to just measure.
And as the previous reply mentioned, surface-mount resistors dispense with this silly color code entirely (though you’ll need a powerful loupe to read the tiny digits on them).
I’ve always wondered exactly how a wire carries information along. I understand it’s electrical pulses along the wire, but what converts it to information that can be received by the user? If it’s a simple on/off thing then what was the point of anything beyond binary since the wire would only essentially be carrying binary signals of yes and no, off and on.
Have you ever played telephone with two paper cups and a string? This article does a good job of explaining the game and how it relates to electrical signals:
http://science.howstuffworks.com/question410.htm
A wire can carry a changing voltage. The speed of change and the magnitude of voltage are two ways varying information can be transmitted on a wire. With the invention of the microphone we have a direct way of converting sound to an electrical signal. The invention of the speaker converts the electrical signal back to sound.
Did I give you an intuitive feeling for how a signal can be more than on and off?
How and why do you use a capacitor, in specific with power supplies? I occasionally see a diagram that needs it but not really more than “used as a surge protector” or “just a good idea”.
In a power supply converting AC to DC, there is always a big capacitor on the output to smooth the voltage. Without it, the voltage would be a 120 cycle per second of pulses, and they would come through on any audio as a buzz. It also acts as a reservoir of electrons for time when the circuit uses more current than the power supply can make.
Capacitors are actually extremely critical components and they do a lot of different things. When you put AC across the cap it will charge up during the rise and discharge during downswing, which will smooth out the pulse.
It’s not able to convert AC to DC or anything (we use diodes for that) but you can use it to turn a choppy line into a solid DC voltage or you can use it with an inductor (which is basically the opposite of a capacitor) to make filters that clip out specific frequencies (in audio).
Capacitors are neurotic little devices that don’t like change (in voltage).
For example, a bypass capacitor is the one that usually hangs off your circuit and goes to ground and seems to have no purpose. Because capacitors can hold a reserve of charge, they release that charge to try and fill any little dip and keep a constant voltage and shunt extra energy out.
Filter capacitors are usually paired with a resistor and attenuate signals outside a frequency range determined by the values of the components.
Coupling capacitors are placed in-line to a signal path so only the AC signal (eg a sine wave) can pass through, but the DC component (eg an offset or bias voltage) is blocked.
This is used if your signal is going into a device that can’t handle a high voltage well. It’s common in between amplifier stages.
I hope that helps a little and is ok info!
One of the things that fascinate me most about electronics is the ability to not only amplify sound but also effect the way it sounds.
One of the things I’d love to learn about electronics is how amplifiers work, so . . . . How do they work? How do we effect the way an electric guitar sounds?
Why can we see electricity when it arcs across two wires, but are normally unable to see it?
You can never see electricity, just as you can’t see wind. You can only see the effects. Sometimes electricity causes heat, and the heat produces light. In other cases, the electrons interact in more interesting ways with matter: When an electron falls from one level to a lower level in an atom, it emits a photon, a particle/wave of light.
I’ve always been confused by inductors. I could never figure out what they’re for, or when I would want one in a circuit.
Inductors generally work with caps. They’re coils that when you have voltage across them they build up a magnetic field and “eats up” voltage and when the voltage goes away the field collapses and creates a burst of voltage.
An inductor is a device that resists a change in current. For another question, I explained how a capacitor resists a change in voltage. If you put the two together in parallel, you create a resonant circuit. Energy stored as voltage in a capacitor will want to flow through the inductor as current, but the inductor resists this. An initial current will be low, but will then grow with time. The voltage meanwhile falls to zero. At this point the inductor has stored energy in a current. So continuing, this current flows into the capacitor, with the voltage starting at zero and eventually growing to be the reverse/negative voltage that we started at. Except for losses to resistance in the components, the process continues in reverse.
This is an oscillation in a resonant LC circuit. The size of the inductor L and capacitor C effect the natural frequency of the oscillation. If you put an external oscillating signal to an LC circuit, like pushing on a swing, the closer the natural oscillation frequency is to your external signal frequency, the larger the voltage/current signals can flow through it. When you go farther away in frequency, the signal is lower. By adjusting the L or C, you can tune to new resonant frequencies.
A tunable LC circuit is useful for selecting a particular frequency radio station with a radio receiver circuit.
Really, I wanna know what milliamps are all about.
If I have 2 9v power supplies and one is 100ma and the other is 500ma, what does that mean? If I plug a 500ma supply into a device that is rated for 100ma what kind of damage would it do to the device if any? Also what is the main function? Are they a seperate part of a power supply circuit or just a measurement that is not always looked at?
mA rating is the current that the power supply can supply. If you you plug a 500mA device into a 100mA supply, you could blow the supply and damage the device. The purpose of the rating is so that you know that the power supply will provide a specific amount of current at the rated voltage.
Your 9 volt power supplies are limited in how much current they can put out before the voltage falls too much to be usable. A device rated at 100ma will work with both your 100ma limited supply, or your 500ma limited supply. Your 500ma limited supply can handle 5 of these 100ma devices at once, while the smaller supply can only supply the one device.
What is the history of the color coding system? How did it come about?
Not sure about the history, but it involves the colors of the rainbow – ROYGBIV (http://en.wikipedia.org/wiki/Roy_G._Biv).
For me it makes remembering values a lot easier, because I only need to remember 4 out of the 10 colors: All I remember is Black is Zero (low end of the scale), Brown is One, then ROY G BV, then gray, then White (high end of the scale) is Nine.
I have a basic understanding of most things electronic, but really am at a lost as how to put it all together to make more complex circuits. Hopefully this book will help.
Ive been baffled by trying to make a simple capacitor charged blinking led circuit that runs off of 1.5v(got that to work but) what i want is when increasing resistance on one part of it, the light blinks faster. ive only been able to do the inverse, make it blink slower.
you’re circuit is right, but by increasing resistance, electricity is taking longer to fill the cap, thus making the light blink slower. I you want it to blink faster, decrease the resistance. A 1k potentiometer hooked up right would do this pretty well and give you a pretty good range of values
Im still trying to learn all of this stuff, every time i look at a circuit im trying to understand the flow. But they seem to break off and there seems to be multiple points between the + and the -
is this normal? how does this not weaken the power in the device? Does this create a circuit within a circuit? And am i over thinking it at this stage?
On your car, you have headlights, taillights, radio, ignition, starter, etc. They are all individual circuits connected in parallel to the battery. When you turn the key to start the car, some of these other circuits are temporaraly disconected from the battery. So the overall car schematic has interaction between subcircuits. The starter motor uses so much power that disconecting the other subcircuits leaves more battery current capacity to do the job. This is especially important if your battery is low on charge.
So, yes, your power supply or battery has limits to how much power it can supply. Adding more circuits in parallel will discharge the battery quicker, and create a voltage drop through resistance in the wires and battery itself. If you load the battery too far, the voltage will drop below the designs of the circuit.
If you can run so much current through a circuit before it starts heating up from resistance, why isn’t this factor used and circuit materials engineering done more, or heard of? Couldn’t energy be shaped with facts like these? Wires with energy flow could be shaped in a similar to car engines.
If you can run so much current through a circuit before it starts heating up from resistance, why isn’t this factor used and circuit materials engineering done more, or heard of? Couldn’t energy be shaped with facts like these? Wires with energy flow could be shaped in a similar manner to car engines.
why can computers only use binary? Wouldn’t it be theoretically possible to use a .5 in addition to 0 and 1? Instead of on and off, on half on, and off, maybe even more middle values.
I’m with Matt and d.moonfire – I think get what a capacitor is (basically) and how it works (sort of), but I don’t really understand what it’s *for*….
Also, what is the “water analogy” representation of a capacitor?
I’m kinda new at this so I wonder, what does arduino has that made it so popular?
1. Arduino is easy to get started with. You don’t need expensive tools, programmers and parts, you just hook it up and go.
2. Arduino is inexpensive. You can get an Arduino for $20-30. Comparable board can cost from $50 up.
3. Arduino is open source. All the software, the language, and even the hardware itself is open source. So the software is free and the hardware is cheap.
4. Arduino has an active community. There are thousands of people in the Arduino community and lots of projects out there that you can use as a starting point for your own unique projects.
5. Arduino is easy to program. One of the tools is a programming language that is similar to well known languages like C/C++ and Java.
There is lots of interest in the Arduino, even by non-technical folks. In fact, Arduino was first created as a way for Artists to add electrical controls to their creations.
Thank you bro, just one more question, Arduino is only a brand that creates boards by getting components together or it makes its componentes like µC, crystals and others.
Arduino the trademarked name of an open source development board and associated open source tools to program it (including a language). Only the original team makes official Arduino boards, all 3rd party boards–even the ones that are identical to the original–can only be called “Arduino Compatible.” It used to cost hundreds of dollars and hours of effort to get your first LED to blink. Now for $20 you can buy a compatible board, plug it in to an $8 breadboard, hook up a battery and you’re in business in 10 minutes. Arduino has democratized the technology, making it available to the general public, where before you practically had to be an electrical engineer to get anything at all done. Arduino is based on the popular Atmel AVR series of microcontrollers.
Thank you man I think I’m ready to enter arduino community now =) .
I read about them, and they seem obvious, then in a few days they seem so complex and mysterious again. It is very frustrating, if only I had more time to dedicate to such things! I am sure this book would help me!
I’m in high school and trying to teach myself electronic through books. Two of my biggest problems/ frustrations is using conversions and formulas between energy, voltage, power etc. and also knowing when to use certain values of a component (ei. resistors or capactors)
Good question, unfortunately it’s a longish answer…
Your basic equation is
OHM’S LAW: V = I*R
that is Voltage = Current * Resistance.
Boring and meaningless. Let’s do an example:
An LED needs about 30mA (30*10^-3 Amperes) to light up, and you have a 9V battery. What value resistor do you need?
Start with V=IR and rearrange to solve for R = V/I.
9V/30mA = 300-ohm resistor.
So the circuit is: +Battery Terminal -> 300-ohm -> (+) LED lead (-) -> -Battery Terminal
Before we connect it together, let’s make sure we’re not going to blow up our Resistor (Let’s assume our 300-ohm is rated for 1/4 Watt).
Power = Voltage*Current (P = V*I)
V and I can be substituted for using Ohms Law, for example:
P = (I*R)*I
P = V*(V/R)
We have 9V and 30mA, so P = (9V)*(30mA) = 0.27-Watts
P = (9V)^2/(300-ohm) = 0.27-Watts
Whoa! That’s a little more than our 1/4-Watt resistor can handle! Let’s play it safe.
You can fix this by putting resistors in parallel (||) to dissipate the power. The current will split across the two resistors coming in, and join back up on the other side so it acts like one resistor.
Resistors in parallel:
REquivalent = 1/((1/R1) + (1/R2))
So, (after setting up a quick calculator in Excel), you look at your kit you pick a 500-ohm and an 820-ohm.
Your Req = 311-ohm,
quickly you calculate the current, I = 9V/311-ohms = 29mA Great!
Quick power calculation to check:
R1: P = (9V^2)/(500-ohm) = 0.162-Watt OK
R2: P = (9V^2)/(820-ohm) = 0.099-Watt OK
Good to go!
(Alternatively, you select a 5-V battery and a 200-ohm resistor for 25mA of current and 1/8-Watt of power!)
Whew! I hope that helps a little bit with your equation question, and gives you an easy project to test the equations!
How do lasers read the Oxygen levels in the blood?
The oxygen probes I use at work use LEDs, not lasers, but the concept is still the same. Hemoglobin carries oxygen in the blood. Each molecule of hemoglobin can carry 4 atoms of oxygen. As hemoglobin becomes more saturated with oxygen, it becomes a brighter red color. The probes use a combination of a red LED and an infrared LED on one side and receptor on the other side. The light shines through a body part (usually a finger or toe, but an earlobe or nose will work too), and differing amounts of light make it out of the other side. By looking at the difference in the absorbtions of the 2 wavelengths, an oxygen saturation can be calculated.
I understand they store electricity, But I can’t seem to understand how to select one.
Shamefully, I can do the math as I’ve studied electricity and magnetism in college level physics, but I never actually learned how to apply that knowledge in any tangible way. So really, what is everything I need in order to get started building solutions with electronics and related components?
I undersand there are red diode lasers and even infra red lasers. I was wondering if there is an ultra violet laser could be used for etching or burning.
When do I use a bipolar transistor and when do I use a MOSFET? I know MOSFET’s are used in most modern electronics, so why would I use a bipolar transistor?
BJTs can output a higher current and are current-controlled device (need a current-driver).
MOSFETs are voltage-controlled. They have a larger bandwidth (switch faster), are stable over temperature and generally introduce less distortion.
I’d love to learn about the Arduino and the ability to test and build circuits.
How do diodes stop current from reversing? I know that it acts like a check valve, but how exactly do they do it?
They’re made of two different materials, designated P and N.
A diode is a sandwich of P and N materials; a transistor is just a diode with another amount P or N material layered on in addition (making it either NPN or PNP).
Think of P material like a grate with holes in it and the N material as a valve mechanism that fills the holes. (correct me if I’m backwards on this, community
When current flows from N to P the “valves” are pushed into the P material and locks off current flow. You still get some leakage (should be about .7 volts but special Zener diodes can leak a specific amount, like 5v) but for the most part the valve is shut. If the current flows the other way then the N material isn’t ‘clogging’ the P material and so it flows freely.
Hope my layman explanation helps.
If I understand your explanation, I think some of this is backward. Instead of valves, the N material has loose electrons. When the electrons flow from N to P, the electrons fill the holes in the P material, and jump from hole to hole continuing the current.
When the diode is reverse biased, the loose N electrons and P holes are pulled apart at the barrier, and current no longer flows. If you put a large enough reverse bias voltage, two types of breakdown can occur. Electrons that were held in their bonds, finally have enough force to break free, and conduct in the reverse bias direction, and in Zener diodes quantum mechanical tunneling allows a current. Regular diodes can be damaged by this because of overheating, but Zener diodes are built for this and have adequate heat sinking. Zener diodes are also designed to breakdown at a particular voltage.
I’ve always seen a resistor connecting to the base of a BJT – if you’re just turning it on and off, do you really need this, or can you connect an IC logic pin directly to the transistor base?
I’ve also had trouble finding a complete V-I curve. What happens when you reverse-bias a BJT? Does it act as a diode and block E/C current? Does current flow through the base?
Always connect a resistor to the base of the BJT. A BJT is a current controlled device, i.e. the amount of current going into the base of the transistor controls the amount of current going through the collector.
When the transistor is ON the voltage from the base to the emitter, V(be), will only get to around 0.7 volts. If you put a logic level, 5 volts, across the base-emitter junction you will damage the device.
Hi,
This actually gets me confused, since I keep reading conflicting information. Yes, it was in the prompt, but I do wish to get an answer to this.
Should I follow the schematic from negative to positive or from positive to negative?
I know that electricity flows from negative to positive, but on British sources they say that schematics are written assuming a positive to negative flow. Later on, they said that it didn’t really matter.
Now, if you have diodes, it seems to me that it does matter. A diode is doing something very different depending on which direction the electricity is actually flowing, or at least I assume that.
So which way should I read them?
Thank Ben Franklin. He assumed current went one way, and so he labeled it as from positive to negative, as in from more to less, with 2 kinds of charge that like to be in balance. This is known as “conventional current”. It wasn’t until they started to understand the atom that they realized that he guessed it backwards. Since the electrons were moving the wrong way, they had to assign them negative charge. This is “electron current”. In any case until you look at the operation of the semiconductors, conventional current is ok.
So most schematics are written in conventional current then?
Yes, schematics assume conventional positive current flow. I like looking at circuits this way because the arrows on the diodes point in the direction of positive current flow. However, I recently read that electronics Instructors are split on which way to teach the subject. In fact the author of the article had taugt it one way for years and then changed to the other! One thing to do would be to get a good book (like Art of Electronics) and use the system used in your book.
What do inductors do in circuits and what is their heat and mechanical equivalents?
I understand what a memristor is, but I don’t quite understand how it works. I have heard many bold claims to the future potential of this amazing circuit element and would love to know how it does what it claims it can do.
It would also be neat to know the application of the memristor for the DIY community and how it would make things better for us, the makers.
Is the Arduino the modern equivalent of the Apple ][? The piece of hardware that is helping to spark a revolution by making electronics accessible to people the same way the Apple ][ made computers accessible to people?
I’d like to second hugoestr’s question about how to read schematics – I always somehow manage to make a horrible mess of circuits while trying to decipher them.
I have similar question, i have a schematic with electrolytic caps. I have a schematic with the symbol for a cap. Its just the 2 little bars, but instead of them either being both filled out or left empty, one is black and the other is white. I thought the white part was negative (like the stripe on a cap) but Idk, and ive looked but cant find an answer. I can reference the datasheet if youd like
Ok, simple enough question but I imagine it can have very different answers.
What is the best educational project for a beginner, where do start learning through practical application and what is the project that teaches the core skillsets?
How do you know when to use a pull down resistor?
I just started arduino related projects and have about a million questions… I have an lolsheild, i don’t really know how to program it, or how it works.. I mean i get how to make a basic multiplexed (i hope i used the right word) screen, but how would that work with arduino? Shift registers also baffle me. What exactly do they do? How do they work? I want to do big projects, maybe a 4×4 LED cube, and once that is mastered, maybe the huge 8×8. I have tried a few large projects, but whenever i do, they usually don’t work. And yes, most of my errors are on a component level. And what exactly is an inductor? Wire wrapped around a core to produce magnetic fields, which re used for what? I hope MAKE doesn’t mind that i downloaded all their circuit skills episodes and put them on my ipod, they’re a real help
So yeah, i have a lot more than one question.. i could go on for a long time but since i need to have one question, how about how a transistor works, it has always bothered me and i bought a few, but do not know how to get them to work
Thanks for the giveaway MAKE! You rock!
Where should a HS freshman start who wants to ‘jump in with both feet’ to the world of electronics?
I do not get the difference between them or understand what they mean. I still can solder stuff and make it work. LOL
Basic electronics uses basic, algebra 1 level math. Ohms law is the most important rule: amps=volts/ohms. (They usually use other symbols for the parts, I=E/R, but here I am using the units for simplicity.) Volts are the pressure of the electricity. Amps are the flow of electrons. Ohms is the resistance to flow. So Ohm’s law just says, “The flow is equal to the pressure divided by the resistance”. Some form of that applies to most things, like cars, or even politics.
I was wondering if the arduino clones can perform all of the functions that an original one can I would love to get involved with the arduino but am confused on what one to purchase and if I should get a starter set and then what kit to buy I do have the getting started with the Arduino book Also a easy explanation to Ohms Law would be great. Thanks
Don’t even know enough to ask an intelligent question! But electronics looks cool and I’d like to learn.
wondering the same
i mean its not like theres some tiny monkey in there stopping the current
you know, i cant remember where i got that quote from…