1 00:00:04,400 --> 00:00:07,760 Speaker 1: Welcome to tex Stuff, a production from I Heart Radio. 2 00:00:12,039 --> 00:00:14,680 Speaker 1: Hey there, and welcome to tech Stuff. I'm your host 3 00:00:14,760 --> 00:00:17,920 Speaker 1: job and Strickland. I'mond executive producer with I Heart Radio 4 00:00:18,000 --> 00:00:21,520 Speaker 1: and how the tech area. It is time for a 5 00:00:21,720 --> 00:00:26,360 Speaker 1: classic episode of tech Stuff. This episode originally published on 6 00:00:26,520 --> 00:00:32,160 Speaker 1: June two thousand fifteen. It is titled The Basic Components 7 00:00:32,280 --> 00:00:35,760 Speaker 1: of Electronics. I bet you'll never guess what it's about. 8 00:00:37,640 --> 00:00:41,000 Speaker 1: Don't be alarmed. I'm going in medias race. This is 9 00:00:41,040 --> 00:00:44,680 Speaker 1: the middle of the email here or really the end. Lastly, 10 00:00:44,800 --> 00:00:47,360 Speaker 1: I was hoping in the future to see topics covered 11 00:00:47,400 --> 00:00:51,360 Speaker 1: like how electronics work, transistors, capascitors, chips, etcetera. I worked 12 00:00:51,360 --> 00:00:53,960 Speaker 1: at Radio Shack for five years and got really interested 13 00:00:53,960 --> 00:00:57,440 Speaker 1: in electronic components, but found them pretty confusing. That is 14 00:00:57,600 --> 00:01:02,120 Speaker 1: perfectly understandable. I still have to look up the various 15 00:01:02,160 --> 00:01:06,120 Speaker 1: components and remind myself what each one does, because I 16 00:01:06,120 --> 00:01:10,119 Speaker 1: don't tend to work with electronic circuits that frequently, and 17 00:01:10,160 --> 00:01:13,840 Speaker 1: I know in general what needs to happen, but sometimes 18 00:01:13,840 --> 00:01:17,640 Speaker 1: I forget the specifics because there's a lot of stuff there, 19 00:01:17,680 --> 00:01:20,800 Speaker 1: and if you aren't familiar, if you're not always working 20 00:01:20,840 --> 00:01:24,080 Speaker 1: in that world, it can very easily slip away from you. 21 00:01:24,200 --> 00:01:27,120 Speaker 1: And we are talking about lots of different components that 22 00:01:27,240 --> 00:01:30,600 Speaker 1: you measure using different units, And after a while you 23 00:01:30,680 --> 00:01:32,720 Speaker 1: just start to you know, if you again, if you're 24 00:01:32,760 --> 00:01:35,039 Speaker 1: not just naturally inclined to this kind of stuff, you 25 00:01:35,040 --> 00:01:37,040 Speaker 1: start to pull your hair out. Except in my case 26 00:01:37,480 --> 00:01:39,360 Speaker 1: that's already been done for me, so I just kind 27 00:01:39,360 --> 00:01:42,360 Speaker 1: of rubbed my head. So let's start with the basics. 28 00:01:43,080 --> 00:01:46,360 Speaker 1: And I know this is going to sound incredibly basic, 29 00:01:46,520 --> 00:01:49,040 Speaker 1: but we have to build a foundation before we can 30 00:01:49,040 --> 00:01:52,480 Speaker 1: start talking about the components. So electronics are all about 31 00:01:52,560 --> 00:01:57,600 Speaker 1: leveraging electricity. Not a big surprise, you're you're leveraging electricity 32 00:01:57,600 --> 00:02:01,280 Speaker 1: in order to do something to accomplis something like a 33 00:02:01,440 --> 00:02:06,440 Speaker 1: radio is meant to receive and amplify radio signals and 34 00:02:06,440 --> 00:02:08,880 Speaker 1: and convert them into acoustic signals so that you can 35 00:02:08,880 --> 00:02:12,760 Speaker 1: actually hear them. That that's a simple example. A flashlight 36 00:02:13,240 --> 00:02:18,480 Speaker 1: is meant to channel electricity to end up powering a 37 00:02:18,600 --> 00:02:21,240 Speaker 1: light bulb, which is essentially a resistor. We will talk 38 00:02:21,280 --> 00:02:25,519 Speaker 1: about those that heats up. We're talking about a basic 39 00:02:25,560 --> 00:02:28,960 Speaker 1: incandescent light bulb here um and gives off light as 40 00:02:28,960 --> 00:02:33,280 Speaker 1: a result. That's your basic use of that kind of electronics. 41 00:02:33,639 --> 00:02:39,119 Speaker 1: So we're gonna talk about how electronics control electricity. These 42 00:02:39,160 --> 00:02:42,760 Speaker 1: basic components are all used to do that so that 43 00:02:42,840 --> 00:02:47,120 Speaker 1: you can accomplish whatever the goal of your electronic device is. Now, 44 00:02:47,160 --> 00:02:50,720 Speaker 1: most electronic devices have lots and lots of different components 45 00:02:50,760 --> 00:02:54,919 Speaker 1: to them, sometimes worked in various configurations, whether they're in 46 00:02:55,040 --> 00:02:57,880 Speaker 1: series or in parallel. I'm not going to get into 47 00:02:57,919 --> 00:03:00,880 Speaker 1: all of that because that's be on what I really 48 00:03:00,919 --> 00:03:05,040 Speaker 1: wanted to focus on in this episode. Instead, in this episode, 49 00:03:05,360 --> 00:03:09,120 Speaker 1: I want to talk about the very basic components and 50 00:03:09,240 --> 00:03:12,519 Speaker 1: what they are intended to do. These are the things 51 00:03:12,560 --> 00:03:15,360 Speaker 1: that make up the circuits that you would see in 52 00:03:15,400 --> 00:03:18,360 Speaker 1: physical circuitry. So if you ever have, uh, you know, 53 00:03:19,200 --> 00:03:21,480 Speaker 1: an old electronic device and you were to take it 54 00:03:21,520 --> 00:03:24,600 Speaker 1: apart and you saw all these little weird do dads 55 00:03:24,680 --> 00:03:27,160 Speaker 1: on a circuit board, I'm gonna tell you what those 56 00:03:27,200 --> 00:03:33,520 Speaker 1: do dads do. Dad. Alright, So first we describe an 57 00:03:33,560 --> 00:03:37,720 Speaker 1: electronics materials is having electrons that fall into certain energy 58 00:03:37,800 --> 00:03:41,240 Speaker 1: bands or electronic bands. Now, the two important ones that 59 00:03:41,320 --> 00:03:44,560 Speaker 1: to talk about are the valence band and the conduction band. 60 00:03:45,200 --> 00:03:47,640 Speaker 1: Electrons and the conduction band are able to move freely 61 00:03:47,680 --> 00:03:50,760 Speaker 1: through the material in question. Assuming the conduction band isn't 62 00:03:50,760 --> 00:03:52,880 Speaker 1: totally full, you can think of it kind of like 63 00:03:52,960 --> 00:03:57,160 Speaker 1: a think of it like a nightclub. It's a nightclub 64 00:03:57,200 --> 00:04:02,480 Speaker 1: that's maybe you know, full, so you can still move 65 00:04:02,520 --> 00:04:06,200 Speaker 1: through it freely. Now that nightclubs packed, you're not going anywhere, 66 00:04:06,280 --> 00:04:08,520 Speaker 1: so there has to be you know, almost but not 67 00:04:08,600 --> 00:04:10,640 Speaker 1: quite full for you to be able to move around. 68 00:04:11,160 --> 00:04:16,120 Speaker 1: That's the conduction band. That's the basics of electrical conductivity. UH. 69 00:04:16,279 --> 00:04:19,279 Speaker 1: Whereas the valance band is kind of this um this 70 00:04:19,279 --> 00:04:22,800 Speaker 1: this basic energy level, and there is a gap between 71 00:04:22,800 --> 00:04:25,680 Speaker 1: the valence band and the conduction band. UH. It is 72 00:04:25,720 --> 00:04:29,200 Speaker 1: called the band gap. And depending upon the material, that 73 00:04:29,240 --> 00:04:31,680 Speaker 1: band gap will be of a certain size, and in 74 00:04:31,720 --> 00:04:35,720 Speaker 1: some cases the gap is insurmountable. You cannot get electrons 75 00:04:36,240 --> 00:04:39,840 Speaker 1: from the valence band into the conductance band, and you 76 00:04:39,880 --> 00:04:43,240 Speaker 1: cannot get them to flow, at least not under normal 77 00:04:43,279 --> 00:04:48,360 Speaker 1: operating circumstances. So in that sense, think of you've got 78 00:04:48,360 --> 00:04:50,520 Speaker 1: a like a holding room before you can get into 79 00:04:50,560 --> 00:04:56,240 Speaker 1: the nightclub, and the the doorway going into the nightclub 80 00:04:56,240 --> 00:04:58,160 Speaker 1: has got a big old bouncer, and that big old 81 00:04:58,160 --> 00:05:01,960 Speaker 1: bouncers not letting anyone through that's your band gap. You 82 00:05:02,160 --> 00:05:06,240 Speaker 1: cannot there's no one even collectively, all of you working together, 83 00:05:06,320 --> 00:05:09,359 Speaker 1: you're not gonna be able to budge that bouncer. That 84 00:05:09,400 --> 00:05:12,200 Speaker 1: would be as if you were in a non conducting 85 00:05:12,279 --> 00:05:14,880 Speaker 1: material and I'll get into more of that later. Whereas 86 00:05:14,880 --> 00:05:18,239 Speaker 1: if you're in a room where there's a wide open 87 00:05:18,320 --> 00:05:20,880 Speaker 1: door and you're allowed to go through as long as 88 00:05:21,120 --> 00:05:24,279 Speaker 1: someone else is coming in, that would mean that you 89 00:05:24,320 --> 00:05:28,039 Speaker 1: could flow through properly. You've got you got electrical electrical 90 00:05:28,080 --> 00:05:31,000 Speaker 1: conductivity going on there, and I'll talk more about that 91 00:05:31,080 --> 00:05:33,880 Speaker 1: in a second. I realized this analogy isn't perfect, but 92 00:05:34,000 --> 00:05:37,279 Speaker 1: I'm just trying to simplify things for those who haven't 93 00:05:37,279 --> 00:05:41,600 Speaker 1: really taken this kind of class in physics. So a 94 00:05:41,680 --> 00:05:45,480 Speaker 1: large gap would represent a great deal of energy needed 95 00:05:45,520 --> 00:05:49,520 Speaker 1: to move electrons from the valence band to the conductance band, 96 00:05:50,480 --> 00:05:53,799 Speaker 1: and sometimes that gap is so large as to be 97 00:05:54,240 --> 00:06:00,360 Speaker 1: impossible to cross again under normal operating conditions. So let's 98 00:06:00,360 --> 00:06:06,920 Speaker 1: look at the basic materials that we talk about in electronics, conductors, insulators, 99 00:06:06,920 --> 00:06:14,120 Speaker 1: and semiconductors. Pretty simple to understand. Conductors have high electrical conductivity. 100 00:06:14,160 --> 00:06:17,479 Speaker 1: That means they facilitate the flow of electrons uh. They 101 00:06:17,480 --> 00:06:20,680 Speaker 1: have a nearly full but not completely full conduction band. 102 00:06:21,000 --> 00:06:24,880 Speaker 1: Electrons can move freely through this material in response to 103 00:06:24,880 --> 00:06:27,960 Speaker 1: an electric field applied to that material. So you apply 104 00:06:28,000 --> 00:06:31,080 Speaker 1: an electrical field to this material, it will then allow 105 00:06:31,080 --> 00:06:34,960 Speaker 1: electrons to flow through freely. This is the stuff that 106 00:06:35,080 --> 00:06:38,080 Speaker 1: moves electrons from point A to point B. You apply 107 00:06:38,160 --> 00:06:41,080 Speaker 1: a voltage across it, you get electrons to flow. That's current, 108 00:06:41,440 --> 00:06:45,680 Speaker 1: Although technically current flows from positive to negative as opposed 109 00:06:45,720 --> 00:06:48,560 Speaker 1: to the flow of electrons, which is from negative to positive. 110 00:06:49,200 --> 00:06:54,960 Speaker 1: We can thank lots of early thinkers for that confusion. 111 00:06:55,520 --> 00:06:58,360 Speaker 1: So current flow and electron flow are in opposite directions, 112 00:06:58,400 --> 00:07:03,080 Speaker 1: Thank you, Benjamin Franklin. Uh. Alright, So then you've got insulators. 113 00:07:03,560 --> 00:07:06,440 Speaker 1: These do not have electrons within the conduction band, or 114 00:07:06,480 --> 00:07:09,680 Speaker 1: they have a full conduction band, so again no room 115 00:07:09,720 --> 00:07:13,000 Speaker 1: for electrons to move around, so there are no free electrons. 116 00:07:13,400 --> 00:07:17,240 Speaker 1: They impede the flow of electrons through that material, and 117 00:07:17,320 --> 00:07:21,560 Speaker 1: most solids fall into this category. Metals are uh an exception, 118 00:07:21,680 --> 00:07:26,640 Speaker 1: but most solids are insulators. So at normal operating parameters, 119 00:07:26,680 --> 00:07:29,080 Speaker 1: you wouldn't be able to apply a strong enough electric 120 00:07:29,160 --> 00:07:33,200 Speaker 1: field to make them conduct electricity. So you could apply 121 00:07:33,240 --> 00:07:36,920 Speaker 1: an electric field to these things, but it wouldn't be 122 00:07:37,000 --> 00:07:40,480 Speaker 1: able to jump that gap between the valence band and 123 00:07:40,520 --> 00:07:44,800 Speaker 1: the conductance band, so it would just stop. You wouldn't 124 00:07:44,800 --> 00:07:47,320 Speaker 1: have any electrical flow through that at all. So we 125 00:07:47,480 --> 00:07:50,720 Speaker 1: use insulators for things like insulation on wires where we 126 00:07:51,160 --> 00:07:56,760 Speaker 1: wrapped the wires in that to help prevent leakage or interference, because, 127 00:07:56,800 --> 00:08:00,160 Speaker 1: as we've talked about many times on this show, the 128 00:08:00,200 --> 00:08:05,400 Speaker 1: flow of electricity is also very closely related to magnetism 129 00:08:05,440 --> 00:08:08,080 Speaker 1: and vice versa. So you have to be able to 130 00:08:08,200 --> 00:08:12,360 Speaker 1: limit interference between different wires if you don't want there 131 00:08:12,400 --> 00:08:17,400 Speaker 1: to be that interaction obviously, otherwise you can end up 132 00:08:17,600 --> 00:08:21,400 Speaker 1: causing shorts, which is when you have an unintended connection 133 00:08:21,440 --> 00:08:24,360 Speaker 1: between two different elements of a circuit and it allows 134 00:08:24,360 --> 00:08:27,440 Speaker 1: electricity to pass from one to the other, almost like 135 00:08:27,480 --> 00:08:29,360 Speaker 1: you think of it like a short cut, you know, 136 00:08:29,360 --> 00:08:32,400 Speaker 1: when we say an electrical short and it means that 137 00:08:32,440 --> 00:08:35,880 Speaker 1: the device itself will not work properly because the electricity 138 00:08:35,920 --> 00:08:38,840 Speaker 1: is not flowing through the pathway you had intended it 139 00:08:38,920 --> 00:08:42,080 Speaker 1: to go in. All right, then we've got semiconductors, and 140 00:08:42,120 --> 00:08:44,880 Speaker 1: we'll talk more about them a little bit later, but 141 00:08:45,000 --> 00:08:48,400 Speaker 1: in general, semi conductors have an almost empty conduction band 142 00:08:48,880 --> 00:08:52,199 Speaker 1: and an almost full valence band, and the band gap 143 00:08:52,360 --> 00:08:56,440 Speaker 1: is relatively narrow, so if you don't apply a strong 144 00:08:56,520 --> 00:08:59,760 Speaker 1: enough electric field, it acts as an insulator. But when 145 00:08:59,840 --> 00:09:02,920 Speaker 1: you apply the right amount of energy and electric field, 146 00:09:02,920 --> 00:09:05,520 Speaker 1: it will allow electrons jump from the valence band to 147 00:09:05,520 --> 00:09:08,520 Speaker 1: the conductor band and move freely within the material. You 148 00:09:08,600 --> 00:09:12,000 Speaker 1: do this by doping the material, which is when you 149 00:09:12,200 --> 00:09:18,160 Speaker 1: insert impurities into the semiconductor on purpose. Doping a semiconductor, 150 00:09:18,240 --> 00:09:24,280 Speaker 1: which is all about introducing impurities specifically at at predetermined levels, 151 00:09:24,920 --> 00:09:27,959 Speaker 1: will determine the energy levels required to do this, and 152 00:09:28,000 --> 00:09:31,200 Speaker 1: that's the basis for solid state electronics. We'll get into 153 00:09:31,240 --> 00:09:35,600 Speaker 1: more about semiconductors towards the end of this. And we 154 00:09:35,679 --> 00:09:39,280 Speaker 1: also have to remember voltage and current, something that I 155 00:09:39,400 --> 00:09:43,600 Speaker 1: always have trouble remembering. So voltage is a lot like 156 00:09:43,679 --> 00:09:46,960 Speaker 1: water pressure, all right. That's that's the the amount of 157 00:09:47,600 --> 00:09:52,320 Speaker 1: electrical pressure being applied, and the higher the voltage, the 158 00:09:52,320 --> 00:09:57,160 Speaker 1: more electrons want to move from the concentration of electrons 159 00:09:57,200 --> 00:10:01,480 Speaker 1: to the more positive side. Now, the actual flow of 160 00:10:01,480 --> 00:10:05,959 Speaker 1: electricity is the current, so they are related but not 161 00:10:06,000 --> 00:10:08,679 Speaker 1: the same thing. So voltage and current, and then you 162 00:10:08,760 --> 00:10:11,280 Speaker 1: multiply those two de patent together and you get the power. 163 00:10:11,679 --> 00:10:15,440 Speaker 1: So voltage times current equals power. Alright, So those are 164 00:10:15,440 --> 00:10:18,520 Speaker 1: your basics. Now we're gonna go through and talk about 165 00:10:18,640 --> 00:10:22,760 Speaker 1: the very individual components and what they do. So first 166 00:10:22,800 --> 00:10:26,840 Speaker 1: we have resistors. Resistor does pretty much what it sounds like. 167 00:10:26,880 --> 00:10:30,640 Speaker 1: It does. It resists but does not halt the flow 168 00:10:30,760 --> 00:10:34,880 Speaker 1: of electricity. I'm gonna talk a lot about electricity in 169 00:10:34,960 --> 00:10:38,160 Speaker 1: terms of water because it is a useful analogy, and 170 00:10:38,360 --> 00:10:42,800 Speaker 1: it's also very common to talk about the similarities between 171 00:10:42,800 --> 00:10:47,000 Speaker 1: electricity flowing and water flowing when you're discussing these components. 172 00:10:47,520 --> 00:10:50,319 Speaker 1: So let's say that you have two different pipes. You've 173 00:10:50,320 --> 00:10:54,040 Speaker 1: got a brand spanking new pipe. It's shiny and beautiful 174 00:10:54,120 --> 00:10:58,880 Speaker 1: and free from any any irregularities, and it allows water 175 00:10:58,920 --> 00:11:02,200 Speaker 1: to flow through the minimum of resistance. That water is 176 00:11:02,240 --> 00:11:05,360 Speaker 1: just flowing right through easily. You've got a second, old, 177 00:11:05,400 --> 00:11:09,440 Speaker 1: gnarly pipe, and this one's got calcium build up in it. 178 00:11:09,559 --> 00:11:11,840 Speaker 1: They're all these bumps and stuff on the inside. So 179 00:11:11,960 --> 00:11:16,600 Speaker 1: water actually encounters resistance friction if you will, as it's 180 00:11:16,600 --> 00:11:20,840 Speaker 1: flowing through, and it does not flow through as easily. 181 00:11:21,440 --> 00:11:24,840 Speaker 1: Resistors are like that old gnarly pipe, and they are 182 00:11:25,400 --> 00:11:30,240 Speaker 1: invented on purpose for specific reasons. So why would you 183 00:11:30,320 --> 00:11:34,520 Speaker 1: want to have an electronic component that actually slows down 184 00:11:34,600 --> 00:11:37,520 Speaker 1: or impedes the flow of electricity for some reason. Well, 185 00:11:38,360 --> 00:11:40,599 Speaker 1: sometimes you have to limit the amount of electricity that 186 00:11:40,640 --> 00:11:43,360 Speaker 1: can flow through part of a circuit within a given 187 00:11:43,400 --> 00:11:47,360 Speaker 1: amount of time, sort of like how a faucet going 188 00:11:47,400 --> 00:11:49,600 Speaker 1: back to water, how fauce it can limit how much 189 00:11:49,600 --> 00:11:52,440 Speaker 1: water it can flow through your water pipes into your sink. 190 00:11:53,160 --> 00:11:56,160 Speaker 1: So you wouldn't want just an on off switch for 191 00:11:56,240 --> 00:11:58,560 Speaker 1: the water coming into your home. That water is at 192 00:11:58,559 --> 00:12:01,320 Speaker 1: a much higher pressure, know it's it's a higher pressure 193 00:12:01,360 --> 00:12:03,800 Speaker 1: to deliver the water to your house. And if all 194 00:12:03,840 --> 00:12:06,040 Speaker 1: you had wasn't on off switch and you flipped it, 195 00:12:06,320 --> 00:12:10,720 Speaker 1: you would have water blasting through the pipe according to 196 00:12:10,800 --> 00:12:12,760 Speaker 1: the amount of pressure that was built up behind it. 197 00:12:13,240 --> 00:12:16,440 Speaker 1: That'd be a little bit nerving, especially if you just 198 00:12:16,440 --> 00:12:19,080 Speaker 1: wanted to have a nice, frusty glass water. So you 199 00:12:19,120 --> 00:12:21,720 Speaker 1: want to have some sort of limiter on that to 200 00:12:21,920 --> 00:12:24,719 Speaker 1: control the amount of water that's or the pressure of 201 00:12:24,760 --> 00:12:27,880 Speaker 1: the water that's coming in. So resistors reduced the amount 202 00:12:27,880 --> 00:12:32,040 Speaker 1: of voltage placed on other electronic components within a circuit 203 00:12:32,440 --> 00:12:34,960 Speaker 1: by restricting the amount of current that can flow through 204 00:12:35,000 --> 00:12:38,800 Speaker 1: the resistor. The reason why this is important is that 205 00:12:39,360 --> 00:12:45,240 Speaker 1: we cannot create a battery for every single type of 206 00:12:45,280 --> 00:12:49,520 Speaker 1: electronic device that's out there. It's not practical. So batteries 207 00:12:49,600 --> 00:12:54,880 Speaker 1: different batteries. Different types of batteries have different voltages. So 208 00:12:55,400 --> 00:13:01,319 Speaker 1: you could, in theory, develop a battery specifically for a 209 00:13:01,360 --> 00:13:05,280 Speaker 1: particular type of electronic device that would not require resistors 210 00:13:05,400 --> 00:13:09,240 Speaker 1: because the battery is providing exactly the voltage needed for 211 00:13:09,440 --> 00:13:13,840 Speaker 1: whatever electronic components are in net. But it's not practical 212 00:13:13,880 --> 00:13:17,480 Speaker 1: to do that for everything. We want standardized batteries, and 213 00:13:17,520 --> 00:13:20,599 Speaker 1: then we use things like resistors to help control the 214 00:13:20,720 --> 00:13:24,280 Speaker 1: voltage in those electronic components so that the right amount 215 00:13:24,320 --> 00:13:27,240 Speaker 1: of voltage is applied to those specific parts of the 216 00:13:27,240 --> 00:13:32,120 Speaker 1: electronic circuit, rather than having to have a billion different 217 00:13:32,120 --> 00:13:36,280 Speaker 1: types of batteries. That would not be practical. So there 218 00:13:36,320 --> 00:13:39,280 Speaker 1: are many different types of resistors designed to work on 219 00:13:39,360 --> 00:13:43,480 Speaker 1: specific amounts of electrical power. Now, some have changeable resistor 220 00:13:43,640 --> 00:13:47,040 Speaker 1: values dependent upon the amount of voltage placed across them. 221 00:13:47,120 --> 00:13:52,560 Speaker 1: They're called nonlinear or voltage dependent resistors. Resistor values can 222 00:13:52,559 --> 00:13:56,400 Speaker 1: also change when the temperature of the resistor changes UH. 223 00:13:56,600 --> 00:13:59,720 Speaker 1: Different types of resistors do this. Some can also be 224 00:14:00,000 --> 00:14:04,360 Speaker 1: mechanically adjusted. So it all depends upon what you need 225 00:14:04,400 --> 00:14:07,120 Speaker 1: the resistor form. Why what you needed to do, that's 226 00:14:07,160 --> 00:14:10,360 Speaker 1: what would determine which type of resistor you would use. 227 00:14:11,000 --> 00:14:13,600 Speaker 1: The unit of measurement for a resistor is the ohm 228 00:14:14,440 --> 00:14:18,400 Speaker 1: oh h M. Resistor values are ten percent apart from 229 00:14:18,440 --> 00:14:22,080 Speaker 1: each other, and resistors are color coded with bands of 230 00:14:22,120 --> 00:14:24,880 Speaker 1: color or or rings of color. So the first ring 231 00:14:24,960 --> 00:14:28,440 Speaker 1: represents the first digit of the resistors value. So what 232 00:14:28,560 --> 00:14:30,160 Speaker 1: you would do is you would look at the first ring, 233 00:14:30,240 --> 00:14:33,040 Speaker 1: whatever color it was, you would cross reference that with 234 00:14:33,640 --> 00:14:38,000 Speaker 1: the with a color UH index, and we'll tell you 235 00:14:38,040 --> 00:14:41,080 Speaker 1: what the value of the resistor is for the first digit. 236 00:14:42,000 --> 00:14:44,640 Speaker 1: The second ring tells you the value of the second digit. 237 00:14:45,120 --> 00:14:48,000 Speaker 1: So then you've got the two the two digits that 238 00:14:48,040 --> 00:14:50,120 Speaker 1: are involved. The third tells you the power of ten 239 00:14:50,200 --> 00:14:54,960 Speaker 1: to multiply by, so it might be ten thousand, and 240 00:14:55,000 --> 00:14:58,200 Speaker 1: then you would multiply. Let's say that your first two 241 00:14:58,200 --> 00:15:00,960 Speaker 1: digits are a twenty two and seven, and you would 242 00:15:01,000 --> 00:15:03,440 Speaker 1: multiply that by ten thousand. You have twenty seven thousand homes. 243 00:15:03,480 --> 00:15:07,000 Speaker 1: There and the fourth ring would tell you the tolerance 244 00:15:07,080 --> 00:15:11,520 Speaker 1: of the resistor plus or minus whatever percentage. Uh. So 245 00:15:11,600 --> 00:15:14,000 Speaker 1: the physical size the resistor and the amount of power 246 00:15:14,040 --> 00:15:16,360 Speaker 1: it can handle tends to be proportional. So in other words, 247 00:15:16,400 --> 00:15:20,080 Speaker 1: the larger the resistor, the more power it can handle. 248 00:15:20,400 --> 00:15:24,920 Speaker 1: In general, So those are resistors covers that basic component. 249 00:15:25,200 --> 00:15:30,280 Speaker 1: Now let's move on to capacitors. Alright, So capacitors are 250 00:15:30,680 --> 00:15:33,760 Speaker 1: similar to batteries and that it's a means of storing 251 00:15:33,920 --> 00:15:40,080 Speaker 1: electrical energy, but unlike batteries, instead of creating an a uh, 252 00:15:40,400 --> 00:15:44,200 Speaker 1: electrical flow through a chemical reaction that is steady the 253 00:15:44,400 --> 00:15:48,960 Speaker 1: entire time, it is designed to release a it's it's 254 00:15:49,160 --> 00:15:55,600 Speaker 1: entire stored electrical charge all at once. So let's say 255 00:15:55,640 --> 00:15:58,680 Speaker 1: they've got two leads of a capacitor. You have a 256 00:15:58,720 --> 00:16:01,680 Speaker 1: difference in voltage across us these two leads. That's when 257 00:16:01,720 --> 00:16:05,240 Speaker 1: a capacitor is charged, So one lead has a greater 258 00:16:05,320 --> 00:16:09,160 Speaker 1: build up of electrons than the other lead does. Uh. Now, 259 00:16:09,200 --> 00:16:12,040 Speaker 1: if you were to connect the leads together, you would 260 00:16:12,040 --> 00:16:15,920 Speaker 1: short them. You would have a discharge of that capacitor, 261 00:16:16,080 --> 00:16:19,200 Speaker 1: and the voltage would equalize across the two, so you 262 00:16:19,240 --> 00:16:22,040 Speaker 1: get a release of a quick burst of electricity, so 263 00:16:22,120 --> 00:16:26,560 Speaker 1: capacitors can pass alternating current freely. A C current will 264 00:16:26,600 --> 00:16:28,880 Speaker 1: just pass through a capacitor as if it were not 265 00:16:29,040 --> 00:16:32,800 Speaker 1: really there. Direct current, however, will charge a capacitor. It 266 00:16:32,800 --> 00:16:36,800 Speaker 1: will have that build up of electrons on one side 267 00:16:37,200 --> 00:16:40,000 Speaker 1: while the other side doesn't get that build up of electrons, 268 00:16:40,040 --> 00:16:43,600 Speaker 1: and then you have that difference in voltage. Alternating current 269 00:16:43,640 --> 00:16:48,640 Speaker 1: just will pass back and forth through it without any problems. 270 00:16:48,640 --> 00:16:52,400 Speaker 1: So capacitors contain the same fundamental parts. You have at 271 00:16:52,480 --> 00:16:57,040 Speaker 1: least two conductive plates separated by a non conductive material 272 00:16:57,120 --> 00:17:00,680 Speaker 1: that's the dielectric. The amount of charge held a capacitor 273 00:17:00,760 --> 00:17:04,000 Speaker 1: is measured in units called faret's. But a faret is 274 00:17:04,119 --> 00:17:08,520 Speaker 1: a large amount of capacitance, so large that you don't 275 00:17:08,600 --> 00:17:12,119 Speaker 1: really talk about a ferret. Instead we end up talking 276 00:17:12,160 --> 00:17:16,000 Speaker 1: about micro ferrets, which are about a well, which are 277 00:17:16,160 --> 00:17:20,639 Speaker 1: one million of a ferret, so much smaller. Ferret, by 278 00:17:20,640 --> 00:17:25,720 Speaker 1: the way, not ferret, two different things. Nice Marmot capacitance 279 00:17:26,000 --> 00:17:29,919 Speaker 1: is dependent upon surface area, so it's directly proportional to 280 00:17:29,960 --> 00:17:33,119 Speaker 1: the surface area of those leads, those those capacity plates. 281 00:17:33,640 --> 00:17:38,040 Speaker 1: Um it is indirectly proportional to the distance between the 282 00:17:38,119 --> 00:17:41,119 Speaker 1: plates so the greater the distance between the plates, the 283 00:17:41,200 --> 00:17:46,760 Speaker 1: lower the capacitance. Uh. It's also uh dependent upon the 284 00:17:46,880 --> 00:17:51,760 Speaker 1: dielectric constant of the insulating material. And they are used 285 00:17:51,800 --> 00:17:54,479 Speaker 1: for things that need a quick release of electricity rather 286 00:17:54,560 --> 00:17:59,000 Speaker 1: than a steady flow. So for example, a traditional flash 287 00:17:59,119 --> 00:18:01,960 Speaker 1: on a camera. So you've got an old camera and 288 00:18:01,960 --> 00:18:05,160 Speaker 1: you've got the the the flash, Uh, you know it 289 00:18:05,200 --> 00:18:07,560 Speaker 1: bursts in this quick burst of light. Will It needs 290 00:18:07,640 --> 00:18:10,560 Speaker 1: that quick It needs access to a quick burst of 291 00:18:10,720 --> 00:18:14,240 Speaker 1: electricity in order to do that, and that's what capacitors 292 00:18:14,240 --> 00:18:16,440 Speaker 1: are good for. And it takes some time for the 293 00:18:16,480 --> 00:18:18,719 Speaker 1: capacitors to build up the charge again so it can 294 00:18:18,760 --> 00:18:21,080 Speaker 1: do it another time. That's sort of you know, if 295 00:18:21,119 --> 00:18:25,000 Speaker 1: you're using the old ones, you hear that noise. It's 296 00:18:25,040 --> 00:18:28,800 Speaker 1: the the discharge and then charging of the capacitors that 297 00:18:29,000 --> 00:18:32,600 Speaker 1: require you to take a moment between taking pictures with 298 00:18:32,680 --> 00:18:38,159 Speaker 1: those old style camera flashes. Now, obviously newer ones use 299 00:18:38,240 --> 00:18:41,760 Speaker 1: different a different approach, but you often have capacitors that 300 00:18:41,840 --> 00:18:46,159 Speaker 1: actually provide the electricity for those Now, the voltage of 301 00:18:46,160 --> 00:18:51,359 Speaker 1: a capacitor cannot change instantly, it's important to remember, and 302 00:18:51,560 --> 00:18:56,720 Speaker 1: quick voltage changes in a capacitor produced large current changes. 303 00:18:57,080 --> 00:19:01,200 Speaker 1: Capacitor store energy in an electric field. The reason I 304 00:19:01,240 --> 00:19:03,600 Speaker 1: mentioned all that is because we're now going to talk 305 00:19:03,880 --> 00:19:09,760 Speaker 1: about inductors, and inductors are kind of, um, the opposite 306 00:19:10,200 --> 00:19:12,919 Speaker 1: of capacitors, or really maybe not even opposite is the 307 00:19:13,000 --> 00:19:15,880 Speaker 1: right way of saying it. In many ways that they 308 00:19:15,920 --> 00:19:19,000 Speaker 1: behave in opposite ways than capacitors do. But we'll get 309 00:19:19,040 --> 00:19:22,120 Speaker 1: to that. We'll be back with more of this classic 310 00:19:22,160 --> 00:19:36,879 Speaker 1: episode of tech stuff after this quick break. So basically, 311 00:19:36,920 --> 00:19:40,639 Speaker 1: an inductor at its most basic level is a coil 312 00:19:40,680 --> 00:19:43,159 Speaker 1: of wires, so sometimes we just call them coils and 313 00:19:43,280 --> 00:19:48,119 Speaker 1: not inductors. Uh. They deal with what is the electrical 314 00:19:48,200 --> 00:19:54,119 Speaker 1: equivalent of momentum. So if you're familiar with momentum, essentially, 315 00:19:54,240 --> 00:19:56,919 Speaker 1: this is that idea that you get a you know, 316 00:19:57,000 --> 00:19:59,400 Speaker 1: objects in motion tend to stay in motion. So let's 317 00:19:59,440 --> 00:20:04,320 Speaker 1: say you've got a large mass moving at a particular velocity. 318 00:20:04,440 --> 00:20:06,800 Speaker 1: It has a certain amount of momentum and you have 319 00:20:06,840 --> 00:20:10,879 Speaker 1: to overcome that momentum to slow down and stop that uh, 320 00:20:10,880 --> 00:20:14,040 Speaker 1: that that mass. So it's the same type of thing 321 00:20:14,119 --> 00:20:17,920 Speaker 1: with inductors, except we're talking about the electrical equivalent of momentum. 322 00:20:17,920 --> 00:20:22,040 Speaker 1: We're talking about the flow of electricity. So again going 323 00:20:22,040 --> 00:20:25,240 Speaker 1: back to the water analogy, Let's say that you've got 324 00:20:25,280 --> 00:20:28,840 Speaker 1: a water hose, a really long one, several hundred feet long, 325 00:20:29,000 --> 00:20:32,400 Speaker 1: and you've coiled it up so it's in a nice 326 00:20:32,480 --> 00:20:36,280 Speaker 1: long coil and it's filled with water. There are gallons 327 00:20:36,480 --> 00:20:39,560 Speaker 1: of water inside this hose, and the end of the 328 00:20:39,600 --> 00:20:41,680 Speaker 1: hose is tilted at such an angle so the water 329 00:20:41,760 --> 00:20:44,440 Speaker 1: is not just flowing right out. You put a plunger 330 00:20:44,480 --> 00:20:47,679 Speaker 1: into the other end and you start to press on 331 00:20:47,760 --> 00:20:51,000 Speaker 1: the plunger to push the water out. Now, all of 332 00:20:51,000 --> 00:20:54,000 Speaker 1: that water is not just going to simultaneously start to 333 00:20:54,119 --> 00:20:56,800 Speaker 1: move together. It actually is going to take some time 334 00:20:57,440 --> 00:21:01,080 Speaker 1: for the pressure you are applying to exert enough force 335 00:21:01,200 --> 00:21:05,240 Speaker 1: to push the water out to overcome the inertia within 336 00:21:05,480 --> 00:21:09,159 Speaker 1: that coil of water hose. And once you get that 337 00:21:09,200 --> 00:21:12,040 Speaker 1: water coming out at the speed at which it can 338 00:21:12,160 --> 00:21:13,920 Speaker 1: come out and you let go of the plunger, the 339 00:21:13,920 --> 00:21:17,840 Speaker 1: plunger is going to continue going down that tube because 340 00:21:17,920 --> 00:21:21,080 Speaker 1: of inertia. That's the same sort of thing with inductors, 341 00:21:21,080 --> 00:21:24,680 Speaker 1: except instead of water, we're talking about electricity. So coils 342 00:21:24,720 --> 00:21:28,199 Speaker 1: of wire will pass D C current but will block 343 00:21:28,520 --> 00:21:31,160 Speaker 1: a C current. So in other words, direct current can 344 00:21:31,240 --> 00:21:36,160 Speaker 1: flow through an inductor, but alternating current would be blocked 345 00:21:36,200 --> 00:21:39,080 Speaker 1: because it cannot flow the opposite way through the coil. 346 00:21:39,800 --> 00:21:43,760 Speaker 1: So that makes it the opposite of capacitors. Remember, capacitors 347 00:21:43,760 --> 00:21:47,240 Speaker 1: would pass alternating current that can flow straight through, but 348 00:21:47,320 --> 00:21:50,480 Speaker 1: would block direct current. Direct current would charge a capacitor 349 00:21:50,520 --> 00:21:52,960 Speaker 1: a capacitor, but could not just flow through the capacitor. 350 00:21:53,320 --> 00:21:56,600 Speaker 1: In this case, direct current can flow through an inductor, 351 00:21:56,680 --> 00:22:00,719 Speaker 1: but a c altering current would be blocked. The standard 352 00:22:00,840 --> 00:22:05,520 Speaker 1: unit of inductance is the henry. I wish I could 353 00:22:05,520 --> 00:22:08,120 Speaker 1: tell you why, but I honestly don't know. I'm sure 354 00:22:08,160 --> 00:22:11,280 Speaker 1: some of you out there, you electricians, are very familiar 355 00:22:11,280 --> 00:22:14,040 Speaker 1: with the reason why and could tell me and feel 356 00:22:14,080 --> 00:22:17,200 Speaker 1: free to I I honestly do not off hand. No, 357 00:22:17,920 --> 00:22:21,240 Speaker 1: the inductance of a coil is indirectly proportional to the 358 00:22:21,359 --> 00:22:25,080 Speaker 1: length of the coil, but directly proportional to the cross 359 00:22:25,200 --> 00:22:29,000 Speaker 1: sectional area of the wire, So, in other words, the 360 00:22:29,040 --> 00:22:32,040 Speaker 1: gauge of the wire is important here. It's also proportional 361 00:22:32,080 --> 00:22:35,000 Speaker 1: to the square of the number of turns in the coil, 362 00:22:35,480 --> 00:22:39,320 Speaker 1: and it's directly proportional to the permeability of the core material. Now, 363 00:22:39,320 --> 00:22:42,560 Speaker 1: the core is whatever this coil is wrapped around. Now 364 00:22:42,560 --> 00:22:44,840 Speaker 1: it could be wrapped around air, or it could be 365 00:22:44,840 --> 00:22:48,760 Speaker 1: wrapped around something like iron, which is incredibly effective. So 366 00:22:49,200 --> 00:22:51,320 Speaker 1: those are that's what we're talking about with the cords, 367 00:22:51,400 --> 00:22:56,399 Speaker 1: whatever the wire or is coiled around. So when current 368 00:22:56,520 --> 00:22:59,560 Speaker 1: first starts flowing into the coil, the coil wants to 369 00:22:59,600 --> 00:23:03,280 Speaker 1: build up a magnetic field. We talked about this again 370 00:23:03,320 --> 00:23:08,439 Speaker 1: and again that you start running electricity through a coil 371 00:23:08,520 --> 00:23:12,439 Speaker 1: of wire that's coiled around like an iron core, like 372 00:23:12,480 --> 00:23:16,800 Speaker 1: a nail, and you start to you create an electro magnet. Well, 373 00:23:16,880 --> 00:23:20,320 Speaker 1: once that field is built. While while the magnetic field 374 00:23:20,359 --> 00:23:22,840 Speaker 1: is building, the coil inhibits the flow of current through 375 00:23:23,040 --> 00:23:26,440 Speaker 1: the wire, But once the field is built, current can 376 00:23:26,480 --> 00:23:30,280 Speaker 1: flow normally through the wire. So if you were to 377 00:23:30,720 --> 00:23:34,360 Speaker 1: have an inductor hooked up to a light bulb, let's 378 00:23:34,359 --> 00:23:37,840 Speaker 1: say and you flip a switch so that you know, 379 00:23:37,920 --> 00:23:40,720 Speaker 1: technically in an electronics we'd say that you close the switch, 380 00:23:40,760 --> 00:23:43,440 Speaker 1: so you have created a closed path so electrons can 381 00:23:43,440 --> 00:23:46,760 Speaker 1: flow through. The electrons would flow through the inductor, which 382 00:23:46,800 --> 00:23:49,560 Speaker 1: would start to build up a magnetic field. So at 383 00:23:49,600 --> 00:23:52,320 Speaker 1: first you would get the light bulb coming on. Then 384 00:23:52,320 --> 00:23:54,520 Speaker 1: it would start to dim a bit because as that 385 00:23:54,600 --> 00:23:58,720 Speaker 1: magnetic field is getting built up the lightbulb, you know, 386 00:23:58,760 --> 00:24:01,080 Speaker 1: the electricity would be it did to the light bulb, 387 00:24:01,080 --> 00:24:03,720 Speaker 1: it would actually act as sort of a resistor, and 388 00:24:03,760 --> 00:24:06,120 Speaker 1: the light bul would start to get dimmer. But then 389 00:24:06,160 --> 00:24:09,360 Speaker 1: eventually that that magnetic field would get charged up as 390 00:24:09,440 --> 00:24:12,919 Speaker 1: much as it can because it's direct current, not alternating current, 391 00:24:13,600 --> 00:24:16,560 Speaker 1: and you would reach a level where it was stabilized. 392 00:24:16,680 --> 00:24:20,439 Speaker 1: Current would flow fine. At that point, you could actually 393 00:24:20,480 --> 00:24:25,639 Speaker 1: turn off the switch, you can open it. In other words, 394 00:24:26,160 --> 00:24:29,440 Speaker 1: the magnetic field around the coil would keep current flowing 395 00:24:29,480 --> 00:24:33,240 Speaker 1: through the coil until that magnetic field collapsed. So even 396 00:24:33,240 --> 00:24:36,560 Speaker 1: though you turn the switch to off, because you have 397 00:24:36,600 --> 00:24:40,280 Speaker 1: an inductor, that light bulb would stay lit until the 398 00:24:40,280 --> 00:24:43,359 Speaker 1: magnetic field and the inductor collapsed, in which case it 399 00:24:43,400 --> 00:24:46,840 Speaker 1: would stop inducing current to flow through and the light 400 00:24:46,840 --> 00:24:50,760 Speaker 1: bulb would go off. So the experience you would have 401 00:24:50,960 --> 00:24:54,520 Speaker 1: is turn the switch on, light bulb comes on, light 402 00:24:54,560 --> 00:24:57,840 Speaker 1: bulb starts to get dim, light bulb gets bright again, 403 00:24:58,080 --> 00:25:00,439 Speaker 1: You turn the switch off, light bulb stays lit for 404 00:25:00,480 --> 00:25:02,960 Speaker 1: a while, and then turns off. That's what it would 405 00:25:03,000 --> 00:25:08,159 Speaker 1: look like to you, So pretty interesting to me now. So, 406 00:25:08,200 --> 00:25:11,679 Speaker 1: an inductor stores energy in its magnetic field, and it 407 00:25:11,720 --> 00:25:14,440 Speaker 1: tends to resist any change in the amount of current 408 00:25:14,640 --> 00:25:18,480 Speaker 1: flowing through it, thus making it different from capacitors. Because 409 00:25:18,480 --> 00:25:23,520 Speaker 1: capacitors store things an electric field, inductor store things energy, 410 00:25:23,800 --> 00:25:27,040 Speaker 1: not just things. Capacitor store energy and electric fields, and 411 00:25:27,240 --> 00:25:32,560 Speaker 1: inductor store energy and magnetic fields. And capacitors resist changes 412 00:25:32,680 --> 00:25:37,720 Speaker 1: to voltage, whereas inductors resist changes to current. So really 413 00:25:37,760 --> 00:25:41,639 Speaker 1: interesting about that. We've got more to say in this 414 00:25:41,800 --> 00:25:52,879 Speaker 1: classic episode of tech stuff after these quick messages. So 415 00:25:52,960 --> 00:25:57,440 Speaker 1: because of this relationship between inductors and capacitors, these two 416 00:25:57,520 --> 00:26:02,119 Speaker 1: different components are sometimes referred together as duel components because 417 00:26:02,119 --> 00:26:06,320 Speaker 1: they they are opposites that complement one another. The current 418 00:26:06,400 --> 00:26:09,479 Speaker 1: in an inductor cannot change instantly the quick current changes 419 00:26:09,520 --> 00:26:12,560 Speaker 1: produced the large voltage, and inductors store their energy in 420 00:26:12,560 --> 00:26:16,400 Speaker 1: those magnetic fields. That's what sets them opposite of capacitors, 421 00:26:16,400 --> 00:26:19,600 Speaker 1: because they are all the opposite of those things. And 422 00:26:19,640 --> 00:26:21,760 Speaker 1: you might wonder, well, what are inductors used for. I mean, 423 00:26:21,760 --> 00:26:25,280 Speaker 1: that light bulb example seems kind of crazy. Well, they're 424 00:26:25,600 --> 00:26:27,400 Speaker 1: used for lots of stuff. For example, if you've ever 425 00:26:27,440 --> 00:26:31,280 Speaker 1: gone to uh, like traffic lights, that are the respond 426 00:26:31,320 --> 00:26:35,040 Speaker 1: to the presence of vehicles. Most of those are using inductors. 427 00:26:35,080 --> 00:26:38,719 Speaker 1: So underneath the pavement where you're driving on top of 428 00:26:39,000 --> 00:26:43,800 Speaker 1: you know, there are giant coils of wire, and when 429 00:26:43,880 --> 00:26:47,240 Speaker 1: you stop your car at a stoplight that has one 430 00:26:47,240 --> 00:26:50,640 Speaker 1: of these systems, your car starts to act as the 431 00:26:50,680 --> 00:26:53,679 Speaker 1: core for that inductor loop. You've got this massive amount 432 00:26:53,680 --> 00:26:58,119 Speaker 1: of steel that's right there that affects the inductance of 433 00:26:58,160 --> 00:27:01,159 Speaker 1: the that cable. You of a meter attached to the 434 00:27:01,160 --> 00:27:05,000 Speaker 1: cable that measures the inductance. So when it measures a 435 00:27:05,160 --> 00:27:09,640 Speaker 1: change in inductance, that meter knows there's a vehicle at 436 00:27:09,680 --> 00:27:13,960 Speaker 1: that location and sends that information to the control unit 437 00:27:14,040 --> 00:27:17,919 Speaker 1: for the traffic system and thus changes the traffic cycle 438 00:27:18,040 --> 00:27:20,919 Speaker 1: so that you get a green light faster. So if 439 00:27:20,960 --> 00:27:24,639 Speaker 1: you're ever at one of those intersections where the the 440 00:27:24,760 --> 00:27:28,200 Speaker 1: light cycles depend heavily upon whether or not their cars 441 00:27:28,280 --> 00:27:33,040 Speaker 1: present at the intersection, that's generally speaking, what is happening. 442 00:27:33,040 --> 00:27:36,159 Speaker 1: You've got these inductors. The inductance changes, sends the message 443 00:27:36,160 --> 00:27:39,320 Speaker 1: to the meter, or rather the meter detects the inductor 444 00:27:39,320 --> 00:27:42,080 Speaker 1: the change in inductance and then sends that onto the 445 00:27:42,119 --> 00:27:46,200 Speaker 1: traffic control system. That will then, at least in theory, 446 00:27:46,600 --> 00:27:50,439 Speaker 1: gets you on your way a little faster. So that's inductors. 447 00:27:52,080 --> 00:27:56,120 Speaker 1: Now let's take a look at transformers, which are more 448 00:27:56,160 --> 00:27:59,320 Speaker 1: than meets the eye. So I'm not talking about autobots 449 00:27:59,359 --> 00:28:02,160 Speaker 1: in Decepticon, as much as I would love to do that, 450 00:28:02,359 --> 00:28:06,040 Speaker 1: instead of talking about the basic electronic component. So let's 451 00:28:06,080 --> 00:28:10,000 Speaker 1: say you've got a single core, like like that iron nail. 452 00:28:10,280 --> 00:28:15,120 Speaker 1: Let's say and you put multiple coils of wire over 453 00:28:15,160 --> 00:28:18,639 Speaker 1: this same iron core, and then you force a DC 454 00:28:18,800 --> 00:28:21,880 Speaker 1: current through one of those coils of wire, not all 455 00:28:21,920 --> 00:28:25,399 Speaker 1: of them, just one. Now, as that current charges, it 456 00:28:25,440 --> 00:28:28,479 Speaker 1: will induce current to flow through the other coils wrapped 457 00:28:28,480 --> 00:28:32,639 Speaker 1: around that same core, and constantly changing the voltage of 458 00:28:32,680 --> 00:28:35,879 Speaker 1: that primary coil. The one that you've got attached to 459 00:28:35,920 --> 00:28:40,000 Speaker 1: some sort of voltage generator, will cause currents that change 460 00:28:40,040 --> 00:28:43,600 Speaker 1: in a similar fashion in the other coils. Now, if 461 00:28:43,640 --> 00:28:46,400 Speaker 1: the other coils have more loops than the primary coil, 462 00:28:46,720 --> 00:28:50,240 Speaker 1: the voltage will be greater, but the current will be lower. 463 00:28:50,360 --> 00:28:52,240 Speaker 1: I'll explain that in a second. So let's say we've 464 00:28:52,280 --> 00:28:54,760 Speaker 1: got we'll make it really simple. We'll just do two coils. 465 00:28:55,560 --> 00:28:58,160 Speaker 1: Let say we've got an iron core and we've got 466 00:28:58,240 --> 00:29:02,200 Speaker 1: a primary wire coiled a fund it ten times, and 467 00:29:02,240 --> 00:29:04,920 Speaker 1: we have a second wire coiled in the same direction 468 00:29:05,000 --> 00:29:08,560 Speaker 1: around that iron core, but it is coiled twenty times, 469 00:29:09,120 --> 00:29:12,760 Speaker 1: and we apply a varying voltage across the primary wire. 470 00:29:13,240 --> 00:29:15,560 Speaker 1: The voltage across the second wire will be twice as 471 00:29:15,640 --> 00:29:19,160 Speaker 1: much because there are twice as many coils, but the 472 00:29:19,240 --> 00:29:21,840 Speaker 1: current will be half as much as that in the 473 00:29:21,880 --> 00:29:25,680 Speaker 1: primary coil. And that's because you have to conserve power. 474 00:29:26,200 --> 00:29:29,120 Speaker 1: You cannot create or destroy power. You have to conserve it. 475 00:29:29,440 --> 00:29:32,600 Speaker 1: And power, like I said earlier, is equal to voltage 476 00:29:32,600 --> 00:29:36,480 Speaker 1: times current. So if we double the voltage, but ultimately 477 00:29:36,520 --> 00:29:38,800 Speaker 1: the power in the secondary coil has to be the 478 00:29:38,840 --> 00:29:41,680 Speaker 1: same as the primary coil, and the only way to 479 00:29:42,080 --> 00:29:46,520 Speaker 1: address that is to have the current. So that's you know, 480 00:29:46,600 --> 00:29:50,680 Speaker 1: that's what happens. So if the second coil is coiled 481 00:29:50,680 --> 00:29:52,720 Speaker 1: in the same direction as the primary, like I was 482 00:29:52,760 --> 00:29:56,520 Speaker 1: saying before, the voltage is in the same polarity as 483 00:29:56,560 --> 00:30:00,720 Speaker 1: that of the generator the primary coil. If second coil 484 00:30:00,840 --> 00:30:04,120 Speaker 1: is coiled in the opposite direction of the primary coil, 485 00:30:04,680 --> 00:30:08,000 Speaker 1: then the voltage is in the opposite polarity from the 486 00:30:08,040 --> 00:30:12,080 Speaker 1: primary coil. Polarity is really important, but also pretty complicated, 487 00:30:12,200 --> 00:30:17,040 Speaker 1: So I'll probably spend another episode to explain that concept 488 00:30:17,200 --> 00:30:20,760 Speaker 1: because it's really a bit much to go into right now. 489 00:30:21,720 --> 00:30:26,280 Speaker 1: But anyway, this is the basics for power transmission using 490 00:30:26,320 --> 00:30:31,240 Speaker 1: alternating current. It's the reason why we have alternating current 491 00:30:31,240 --> 00:30:34,200 Speaker 1: distributing our power instead of direct current. So then that 492 00:30:34,320 --> 00:30:39,480 Speaker 1: old Tesla versus Edison argument, really i should say Westinghouse 493 00:30:39,720 --> 00:30:43,760 Speaker 1: versus Edison argument, where Edison was saying direct current was 494 00:30:43,840 --> 00:30:47,320 Speaker 1: best and westing Us was saying no alternating current was best. 495 00:30:48,040 --> 00:30:51,320 Speaker 1: The things that let alternating current win out over direct 496 00:30:51,360 --> 00:30:56,200 Speaker 1: current where that using transformers you could boost the voltage 497 00:30:56,280 --> 00:31:01,160 Speaker 1: to huge high voltage numbers, which were great for power transmission. 498 00:31:01,440 --> 00:31:06,440 Speaker 1: You could transmit over vast distances using high voltage wires, 499 00:31:06,520 --> 00:31:09,200 Speaker 1: and then you would use other transformers on the opposite 500 00:31:09,320 --> 00:31:12,840 Speaker 1: end to step down the voltage until you reach the 501 00:31:12,920 --> 00:31:15,040 Speaker 1: level that was safe for homes, which in the United 502 00:31:15,040 --> 00:31:18,680 Speaker 1: States is two forty volts. Uh. Now, keep in mind 503 00:31:18,680 --> 00:31:21,360 Speaker 1: that when you're talking about transmission voltages, it could be 504 00:31:21,400 --> 00:31:24,120 Speaker 1: anywhere between a hundred fifty five thousand to seven d 505 00:31:24,200 --> 00:31:28,760 Speaker 1: sixty thousand volts, So we're talking huge differences here, and 506 00:31:28,800 --> 00:31:32,440 Speaker 1: it's all because you can use this basic element of 507 00:31:32,480 --> 00:31:36,880 Speaker 1: electronics with these transformers to step up or step down 508 00:31:36,880 --> 00:31:41,160 Speaker 1: the voltage simply by using different coils along a core. 509 00:31:42,240 --> 00:31:46,240 Speaker 1: So that was incredibly useful. You could end up transmitting 510 00:31:46,240 --> 00:31:49,600 Speaker 1: power over great distances. Direct current, however, is very different. 511 00:31:50,000 --> 00:31:52,760 Speaker 1: It is most efficient if it is close to whatever 512 00:31:52,840 --> 00:31:56,680 Speaker 1: the load is on the line. So the load is 513 00:31:56,720 --> 00:31:59,800 Speaker 1: whatever the electricity is meant to power. So in the 514 00:31:59,840 --> 00:32:02,880 Speaker 1: case of homes, you would want the power plant to 515 00:32:02,920 --> 00:32:06,800 Speaker 1: be relatively close to the homes that are receiving electricity. 516 00:32:06,880 --> 00:32:10,560 Speaker 1: If you were using direct current, um this is you know, 517 00:32:10,840 --> 00:32:14,600 Speaker 1: it would be incredibly useful to have direct current powering 518 00:32:14,600 --> 00:32:18,080 Speaker 1: our homes because most of the stuff we have relies 519 00:32:18,280 --> 00:32:23,000 Speaker 1: on direct current. It actually has to convert the alternating 520 00:32:23,040 --> 00:32:26,120 Speaker 1: current that comes to the house into direct current. You 521 00:32:26,160 --> 00:32:29,840 Speaker 1: have these converters that are part of the electronics that 522 00:32:29,920 --> 00:32:32,240 Speaker 1: allow it to do that. If you had direct current 523 00:32:32,320 --> 00:32:36,200 Speaker 1: being uh supplied directly to your house, you wouldn't need 524 00:32:36,240 --> 00:32:40,160 Speaker 1: the conversion part of those devices. However, you wouldn't be 525 00:32:40,160 --> 00:32:42,800 Speaker 1: able to transmit it over great distances like you can 526 00:32:42,880 --> 00:32:46,800 Speaker 1: with alternating current. So in case you're wondering about the 527 00:32:46,840 --> 00:32:49,720 Speaker 1: power grids in the United States. We I mentioned that 528 00:32:49,800 --> 00:32:52,800 Speaker 1: you have those those high voltage lines that are carrying 529 00:32:52,800 --> 00:32:57,360 Speaker 1: between a d to center sixty volts. When you get 530 00:32:57,400 --> 00:33:01,960 Speaker 1: to distribution levels, you step down that voltage to less 531 00:33:01,960 --> 00:33:04,600 Speaker 1: than ten thousand volts typically, and then you get to 532 00:33:04,680 --> 00:33:08,120 Speaker 1: distribution busses that have transformers that reduce it further to 533 00:33:08,360 --> 00:33:11,120 Speaker 1: seven thousand, two hundred volts or less. And then you 534 00:33:11,200 --> 00:33:13,560 Speaker 1: have the homes that are connected to a final transformer 535 00:33:13,640 --> 00:33:16,400 Speaker 1: that step it down again to the voltage of volts 536 00:33:16,480 --> 00:33:24,920 Speaker 1: or so. So incredibly useful and here at how stuff works. Recently, 537 00:33:25,160 --> 00:33:27,680 Speaker 1: as of the recording of this podcast, we had a 538 00:33:27,800 --> 00:33:32,320 Speaker 1: lovely transformer fire right next to the building we work in, 539 00:33:32,440 --> 00:33:35,160 Speaker 1: which cut power to our part of the building for 540 00:33:35,240 --> 00:33:38,360 Speaker 1: some time. So if you've ever been near a transformer 541 00:33:38,400 --> 00:33:41,800 Speaker 1: when it's blown, it's a pretty spectacular thing. It's usually 542 00:33:41,920 --> 00:33:45,040 Speaker 1: lots of sparks and a really loud bang and often 543 00:33:45,120 --> 00:33:50,200 Speaker 1: requires the work of dedicated personnel to repair. And it 544 00:33:50,280 --> 00:33:53,520 Speaker 1: does also typically mean that you have a loss of 545 00:33:53,600 --> 00:33:59,000 Speaker 1: power for at least a localized area. Pretty impressive when 546 00:33:59,040 --> 00:34:02,000 Speaker 1: it happens. Luckily, it doesn't happen all that frequently the 547 00:34:02,120 --> 00:34:06,160 Speaker 1: electrical storms and areas of or times of great use 548 00:34:06,800 --> 00:34:11,160 Speaker 1: can make the more vulnerable. Now let's move on to 549 00:34:11,719 --> 00:34:15,439 Speaker 1: semiconductors and how they are used in electronics. So we've 550 00:34:15,480 --> 00:34:18,000 Speaker 1: got lots of different uses for semiconductors. I'm going to 551 00:34:18,120 --> 00:34:21,839 Speaker 1: talk about two specific ones. There are diodes. Diodes are 552 00:34:21,840 --> 00:34:24,960 Speaker 1: really useful. They allow current to flow in only one direction, 553 00:34:25,000 --> 00:34:27,840 Speaker 1: so it's like a one way channel or a valve. 554 00:34:28,200 --> 00:34:30,760 Speaker 1: So electricity flowing one way is fine, but it cannot 555 00:34:30,800 --> 00:34:34,799 Speaker 1: flow back the other way, and semiconductor doping allows for 556 00:34:34,840 --> 00:34:37,839 Speaker 1: this to happen. Remember I mentioned earlier. Doping is when 557 00:34:37,880 --> 00:34:41,719 Speaker 1: you have introduced impurities into the semiconductor material to give 558 00:34:41,760 --> 00:34:46,200 Speaker 1: its specific UH features. So there are two different types 559 00:34:46,800 --> 00:34:49,680 Speaker 1: that we're going to talk about. There's IN type layers 560 00:34:49,760 --> 00:34:52,000 Speaker 1: of semiconductors, so you can think of that as an 561 00:34:52,040 --> 00:34:56,239 Speaker 1: excess of electrons. It has lots of negative electrons that 562 00:34:56,280 --> 00:34:59,560 Speaker 1: are just ready to flow out of there. And then 563 00:34:59,600 --> 00:35:03,880 Speaker 1: you have of P type layers, and these have electron 564 00:35:03,960 --> 00:35:06,000 Speaker 1: holes or at least you know, in other words, of 565 00:35:06,000 --> 00:35:10,040 Speaker 1: the capacity to take on electrons. So if you pair 566 00:35:10,080 --> 00:35:13,560 Speaker 1: this together, you get what's called a P N diode, 567 00:35:13,600 --> 00:35:16,280 Speaker 1: which all only allows electricity to flow in one direction. 568 00:35:16,480 --> 00:35:20,000 Speaker 1: It can the electrons can come through UH and flow 569 00:35:20,120 --> 00:35:24,200 Speaker 1: to the holes, but they can't go the other way, 570 00:35:24,280 --> 00:35:28,040 Speaker 1: so very useful and electronic components where you need to 571 00:35:28,080 --> 00:35:31,000 Speaker 1: direct the flow of electricity along a particular path and 572 00:35:31,040 --> 00:35:35,839 Speaker 1: prevent it from coming back through that pathway. Transistors are 573 00:35:35,880 --> 00:35:38,960 Speaker 1: another type of semiconductor that use a small amount of 574 00:35:38,960 --> 00:35:43,000 Speaker 1: current to control a large amount of current. So while 575 00:35:43,040 --> 00:35:47,400 Speaker 1: a diode is p n, transistors are either P n 576 00:35:47,560 --> 00:35:51,719 Speaker 1: P or N p n, and if you apply an 577 00:35:51,719 --> 00:35:54,520 Speaker 1: electrical current to the center layer, which is also known 578 00:35:54,560 --> 00:35:57,480 Speaker 1: as the base, electrons will move from the N type 579 00:35:57,520 --> 00:36:00,319 Speaker 1: side to the P type side, and that initial small 580 00:36:00,360 --> 00:36:02,719 Speaker 1: current allows for much larger current to flow through the 581 00:36:02,719 --> 00:36:07,920 Speaker 1: material at that point. So transistors act as switches or amplifiers. 582 00:36:08,520 --> 00:36:12,720 Speaker 1: Incredibly useful. So when we talk about transistors in solid 583 00:36:12,760 --> 00:36:16,279 Speaker 1: state electronics, these are the things that allow us to 584 00:36:17,120 --> 00:36:21,799 Speaker 1: build logic circuits. And it's because we can allow electrons 585 00:36:21,840 --> 00:36:25,400 Speaker 1: to either flow or prevent them from flowing. It's also 586 00:36:25,520 --> 00:36:28,840 Speaker 1: why things like electron tunneling can be such a problem. 587 00:36:29,520 --> 00:36:33,080 Speaker 1: Electron tunneling is a quantum effect, so you can think 588 00:36:33,080 --> 00:36:36,319 Speaker 1: of an electron as not really existing in a specific 589 00:36:36,640 --> 00:36:40,400 Speaker 1: point in space at any given time, but rather having 590 00:36:40,440 --> 00:36:44,560 Speaker 1: the potential to exist in an area of space at 591 00:36:44,600 --> 00:36:47,279 Speaker 1: any point in time. So think of it like a 592 00:36:47,280 --> 00:36:52,200 Speaker 1: cloud where an electron could be, and that cloud covers 593 00:36:52,239 --> 00:36:54,759 Speaker 1: all the potential places the electron could be, and there's 594 00:36:54,840 --> 00:36:58,600 Speaker 1: different probability for different parts of the cloud. If your 595 00:36:58,760 --> 00:37:03,040 Speaker 1: transistor gates are so small, so narrow, so thin, I 596 00:37:03,080 --> 00:37:06,600 Speaker 1: guess I should say not narrow, that the cloud of 597 00:37:06,680 --> 00:37:11,160 Speaker 1: potential can overlap the transistor gate. That means there is 598 00:37:11,200 --> 00:37:15,240 Speaker 1: the possibility that at some point the electron could exist 599 00:37:15,320 --> 00:37:17,719 Speaker 1: on the other side of the transistor gate, even if 600 00:37:17,719 --> 00:37:21,840 Speaker 1: the gate never opened. And if there's a possibility, that 601 00:37:21,880 --> 00:37:24,480 Speaker 1: means sometimes it does appear on the other side of 602 00:37:24,480 --> 00:37:27,480 Speaker 1: the gate. We call it electron tunneling. It's not really tunneling. 603 00:37:27,600 --> 00:37:30,279 Speaker 1: It's just if there is the possibility they could be 604 00:37:30,320 --> 00:37:33,120 Speaker 1: on the other side, sometimes it is on the other side, 605 00:37:33,760 --> 00:37:37,000 Speaker 1: which means that you cannot actually control the flow of electrons. 606 00:37:37,080 --> 00:37:40,120 Speaker 1: In that case, it would mean that your transistors would 607 00:37:40,120 --> 00:37:42,160 Speaker 1: be ineffective in doing what they're supposed to do. They 608 00:37:42,160 --> 00:37:44,920 Speaker 1: wouldn't really be able to act to switches reliably and 609 00:37:44,920 --> 00:37:49,120 Speaker 1: you would get errors in your computations. I might work 610 00:37:49,480 --> 00:37:51,719 Speaker 1: most of the time and then only some of the 611 00:37:51,760 --> 00:37:54,600 Speaker 1: time not work, but even then that's problematic, which is 612 00:37:54,640 --> 00:37:59,120 Speaker 1: one of the engineering challenges that transistor designers and multi 613 00:37:59,640 --> 00:38:02,960 Speaker 1: around their microprocessor designers encounter all the time, you know. 614 00:38:03,080 --> 00:38:08,320 Speaker 1: Finding new materials that are better at acting as transistors 615 00:38:08,320 --> 00:38:12,120 Speaker 1: switches it's a big part of it. And coming up 616 00:38:12,160 --> 00:38:15,919 Speaker 1: with different architectures to really take advantage of electron flow 617 00:38:16,000 --> 00:38:19,040 Speaker 1: is another big part of it, all right. So those 618 00:38:19,080 --> 00:38:22,920 Speaker 1: are the basics the basic electronic components that you can 619 00:38:22,960 --> 00:38:26,080 Speaker 1: talk about with, you know, if you're looking at it 620 00:38:26,120 --> 00:38:28,719 Speaker 1: from a very high level. Obviously there's tons of other 621 00:38:28,760 --> 00:38:31,040 Speaker 1: stuff that I didn't get into, and some of it 622 00:38:31,080 --> 00:38:36,080 Speaker 1: just requires you to pair up or otherwise put into 623 00:38:36,120 --> 00:38:38,759 Speaker 1: series or parallels some of the components I've mentioned to 624 00:38:39,120 --> 00:38:43,040 Speaker 1: to get whatever effects you want. I hope you enjoyed 625 00:38:43,080 --> 00:38:45,600 Speaker 1: that classic episode of tech Stuff as we covered the 626 00:38:45,640 --> 00:38:49,040 Speaker 1: basic components of electronics. It's probably something I'll end up 627 00:38:49,080 --> 00:38:53,239 Speaker 1: covering again in various Tech Stuff tidbits episodes where I 628 00:38:53,320 --> 00:38:58,319 Speaker 1: really focus on specific components and their place in electronics 629 00:38:58,360 --> 00:39:02,080 Speaker 1: and their purpose. Because us you can always do a 630 00:39:02,080 --> 00:39:05,319 Speaker 1: better job, right. I mean, I'm always proud of the 631 00:39:05,320 --> 00:39:08,880 Speaker 1: work I do, but I also recognize when I could 632 00:39:08,920 --> 00:39:11,839 Speaker 1: do it even better, and I think it's about time 633 00:39:11,880 --> 00:39:14,239 Speaker 1: I try and do that. If you have suggestions for 634 00:39:14,280 --> 00:39:16,480 Speaker 1: topics I should cover in future episodes of tech Stuff, 635 00:39:16,520 --> 00:39:18,600 Speaker 1: reach out to me on Twitter to handle for the 636 00:39:18,600 --> 00:39:21,799 Speaker 1: show is tech Stuff hs W, and I'll talk to 637 00:39:21,800 --> 00:39:30,399 Speaker 1: you again really soon. Text Stuff is an I Heart 638 00:39:30,480 --> 00:39:34,239 Speaker 1: Radio production. For more podcasts from I Heart Radio, visit 639 00:39:34,280 --> 00:39:37,319 Speaker 1: the I Heart Radio app, Apple Podcasts, or wherever you 640 00:39:37,440 --> 00:39:38,760 Speaker 1: listen to your favorite shows.