WEBVTT - Listener Mail Grab Bag 0:00:04.240 --> 0:00:07.800 Get in touch with technology with text Stuff from hast 0:00:07.800 --> 0:00:15.240 dot com. Heyl and welcome to text Stuff. I'm Jonathan Strickland, 0:00:15.240 --> 0:00:17.919 and today I thought I would address some listener mail. 0:00:18.040 --> 0:00:20.400 I haven't done that in a while. And by address, 0:00:20.480 --> 0:00:23.320 I mean read it and answer it, as opposed to 0:00:23.520 --> 0:00:26.000 spinning out an address. You know what I meant at 0:00:26.000 --> 0:00:28.560 any rate to We're going to be looking at several 0:00:28.680 --> 0:00:34.120 questions and comments, including a correction, and also a little 0:00:34.120 --> 0:00:37.040 bit later, I'm going to bring in a special mystery 0:00:37.120 --> 0:00:40.800 guest to talk about one of the specific pieces that 0:00:40.840 --> 0:00:43.800 were sent in to me. So let's get started. The 0:00:43.880 --> 0:00:48.080 first message says, hello, longtime listener, first time emailer. I 0:00:48.120 --> 0:00:50.680 wanted to slip in a quick correction in regards to 0:00:50.720 --> 0:00:54.120 the Aircraft Carriers episode. In the episode, you said that 0:00:54.200 --> 0:00:57.600 the US aircraft carrier, the Hornet, was sunk. It's actually not. 0:00:57.880 --> 0:01:01.760 It's anchored in Oakland, California, across the Bay from San Francisco, 0:01:02.120 --> 0:01:04.600 and it's open as a museum to teach visitors about 0:01:04.680 --> 0:01:08.360 how aircraft carriers work. The flight deck, maintenance deck, and 0:01:08.440 --> 0:01:11.240 some lower decks are open to explore with or without 0:01:11.280 --> 0:01:14.560 a tour. The island and engine room are open for tours. 0:01:14.760 --> 0:01:18.600 There's even an Apollo capsule on board, as the Hornet 0:01:18.680 --> 0:01:21.800 was the recovery ship for two Apollo missions. If you're 0:01:21.800 --> 0:01:27.120 ever in or around Oakland, check it out. Regards Alan, Alan, 0:01:27.240 --> 0:01:31.560 thanks for sending in that correction. That's really awesome. The 0:01:31.600 --> 0:01:33.360 Hornet was one of the stories that I thought was 0:01:33.360 --> 0:01:36.800 particularly cool, and uh, and on it was an honest 0:01:36.840 --> 0:01:39.440 mistake on my part. I had so many notes about 0:01:39.480 --> 0:01:42.560 so many different aircraft carriers, and I should have been 0:01:42.560 --> 0:01:45.759 more careful making sure that all of those were accurate. 0:01:46.319 --> 0:01:50.640 And uh, Scott is not his fault at all. It's 0:01:50.720 --> 0:01:56.600 all on me. I shall admonish myself repeatedly. Next, Dan 0:01:56.800 --> 0:02:03.200 from Twitter asked, did I buy an Apple Uch? No? Okay, 0:02:03.240 --> 0:02:05.680 well we're ready to move on. Well, I guess I 0:02:05.680 --> 0:02:08.360 can address this a little further. Uh, I did not 0:02:08.520 --> 0:02:11.560 buy an Apple watch. I don't have an iPhone, so 0:02:11.720 --> 0:02:14.840 an Apple watch would be useless to me, and I 0:02:14.880 --> 0:02:18.679 don't want to invest in an iPhone just to get 0:02:18.720 --> 0:02:21.600 an Apple watch. That would end up being an incredibly 0:02:21.800 --> 0:02:28.240 expensive endeavor. I mean, you're talking around bucks for the watch, 0:02:28.600 --> 0:02:31.200 and that's you know, before you really start looking at 0:02:31.280 --> 0:02:34.400 really nice bands. Or anything like that. Then you've got 0:02:34.400 --> 0:02:37.000 another couple of hundred bucks for the iPhone, plus the 0:02:37.400 --> 0:02:40.240 monthly fee for it and everything, and all of my 0:02:40.320 --> 0:02:44.160 stuff is currently in the Android operating system universe. I 0:02:44.480 --> 0:02:48.240 use a Nexus six as my smartphone. That's not a 0:02:48.280 --> 0:02:50.720 plug for Android, it's not a plug for the Nexus 0:02:50.760 --> 0:02:54.840 line of phones. I like it, and I'm used to it, 0:02:54.880 --> 0:02:58.400 and all of my stuff is in that ecosystem, so 0:02:58.440 --> 0:03:02.400 it would be very arduous to switch to a different 0:03:02.520 --> 0:03:05.960 one at this point. I think the Apple Watches an 0:03:06.000 --> 0:03:10.400 interesting product. I'm curious how well it will do in 0:03:10.440 --> 0:03:12.720 the long run. As I record this, there are plenty 0:03:12.720 --> 0:03:17.400 of stories about the Apple Watch getting some recalls because 0:03:17.680 --> 0:03:21.520 of a faulty vibrating motor that's in some of them, 0:03:22.120 --> 0:03:25.520 and that the production may have slowed down quite a bit, 0:03:25.560 --> 0:03:27.720 which means it's going to take even longer for people 0:03:27.720 --> 0:03:31.680 to get their pre ordered watches. Um it's it's a 0:03:31.680 --> 0:03:35.800 bit of an issue for Apple, And honestly, the wearables 0:03:36.400 --> 0:03:39.000 field is still one of those where a lot of 0:03:39.000 --> 0:03:42.480 people are expressing a lot of skepticism about, you know what, 0:03:42.480 --> 0:03:44.960 what's actually the utility of a smart watch? Is there 0:03:45.000 --> 0:03:49.520 a need for it? Um, I own a Pebble, which 0:03:49.560 --> 0:03:53.360 I would say is a smart ish watch. It is 0:03:53.560 --> 0:03:56.360 good for giving me notifications that are coming through my phone, 0:03:56.400 --> 0:03:59.280 which is actually really useful for me. I don't always 0:03:59.320 --> 0:04:02.160 notice when my phone vibrates in my pocket, even though 0:04:02.200 --> 0:04:04.600 the next of six is as large as some countries. 0:04:05.080 --> 0:04:09.000 I don't always notice when it's vibrating. However, the motor 0:04:09.040 --> 0:04:11.280 that's inside my watch, when it vibrates on my wrist, 0:04:11.360 --> 0:04:15.080 I absolutely noticed that. And uh, it gives me the 0:04:15.120 --> 0:04:17.719 notifications of who is calling or if I've received a 0:04:17.760 --> 0:04:21.440 text message or some other notification. And I love that. 0:04:21.440 --> 0:04:24.560 That to me is perfect, And uh, you know, it's 0:04:24.600 --> 0:04:28.400 it's not super high tech as far as smart watches go. 0:04:28.520 --> 0:04:31.400 It's not like there's a whole bunch of other usefulness 0:04:31.480 --> 0:04:33.160 with it, apart from some of the cool apps you 0:04:33.200 --> 0:04:35.600 can have, and you can do some controls with your smartphone, 0:04:35.640 --> 0:04:39.040 like advancing through tracks in an audio list, that kind 0:04:39.040 --> 0:04:42.120 of thing. That stuff is interesting and neat, but it 0:04:42.160 --> 0:04:45.039 doesn't have a whole lot of utility beyond that. The 0:04:45.080 --> 0:04:49.440 Apple Watch obviously is supposed to be more robust, and 0:04:49.480 --> 0:04:53.120 I hope it does well because I want to see 0:04:53.240 --> 0:04:57.080 this kind of technology. This, this whole branch of technology 0:04:57.120 --> 0:05:01.800 continue and advance and evolve. And my worry is that 0:05:01.880 --> 0:05:05.200 if the Apple Watch ultimately does not do well, because 0:05:05.240 --> 0:05:09.839 it's such a high profile product, it could sink the 0:05:10.000 --> 0:05:14.159 entire branch of technology or set it back by a 0:05:14.200 --> 0:05:16.599 couple of years. It kind of reminds me of the 0:05:16.680 --> 0:05:21.279 days when virtual reality things were coming out and people 0:05:21.279 --> 0:05:23.680 were first getting a chance to actually use them, and 0:05:23.720 --> 0:05:27.880 they became disappointed, disenchanted with the technology that they thought 0:05:27.920 --> 0:05:30.680 was going to be amazing and turned out not to 0:05:30.760 --> 0:05:33.200 be as amazing as they had hoped, and it's set 0:05:33.240 --> 0:05:37.800 the entire field back by at least five years because 0:05:37.800 --> 0:05:40.440 no one wanted to fund something that people no longer 0:05:40.520 --> 0:05:43.880 had any interest or faith in. So my hope is 0:05:43.920 --> 0:05:46.200 that the Apple Watch does well. I do not plan 0:05:46.279 --> 0:05:48.560 to get one again, because I don't have an iPhone. 0:05:49.320 --> 0:05:51.560 I may end up picking up a different smart watch. 0:05:51.600 --> 0:05:56.360 There were a few that I supported on various crowdsourcing campaigns. 0:05:57.000 --> 0:06:00.240 I'm still waiting on all three of the one that 0:06:00.320 --> 0:06:03.400 I supported, one of which is not even a smart watch. 0:06:03.440 --> 0:06:07.839 It's it's a just a cool concept watch. And so 0:06:09.000 --> 0:06:10.800 I don't think i'd be eager to jump on the 0:06:10.800 --> 0:06:14.360 smart watch train even if I did have an iPhone, 0:06:14.480 --> 0:06:19.080 simply because I've already spent money on watches that I 0:06:19.120 --> 0:06:23.920 don't have. Um and that's another discussion for another day. 0:06:23.960 --> 0:06:30.720 The entire idea of crowdsourcing, you know, crowdfunding a technology project. 0:06:30.920 --> 0:06:33.920 Is that a good idea? What are the dangers? I 0:06:33.960 --> 0:06:36.320 should probably do a full episode about that. I know 0:06:36.360 --> 0:06:39.240 I've talked about once or twice in previous episodes, but 0:06:39.440 --> 0:06:42.440 we should probably go into an in depth discussion about 0:06:42.640 --> 0:06:45.880 what is What should your expectations be if you participate 0:06:45.920 --> 0:06:48.359 in that sort of thing. So there's your long answer 0:06:48.640 --> 0:06:53.080 to your simple question. Uh no, And because all right, 0:06:53.120 --> 0:06:55.200 we'll move on to the next one. Luke on Twitter 0:06:55.279 --> 0:06:58.320 asks how soon I expect we'll see stores like Kinko's 0:06:58.360 --> 0:07:01.560 get three D printers for customers to us. I think 0:07:01.600 --> 0:07:05.800 that's actually gonna be probably at least a couple of 0:07:05.880 --> 0:07:08.840 years further down the line from the thing I think 0:07:08.839 --> 0:07:10.720 three D pryers are really going to be useful for 0:07:11.320 --> 0:07:16.400 is gonna be on demand fabrication for small businesses, meaning 0:07:16.640 --> 0:07:19.680 that instead of having a giant furniture store with an 0:07:19.760 --> 0:07:25.280 enormous warehouse, like Ikea, where you've got, you know, tons 0:07:25.600 --> 0:07:29.480 of inventory, and you have no way of knowing how 0:07:29.480 --> 0:07:33.080 how well one is going to sell versus other versions 0:07:33.120 --> 0:07:35.400 of the same sort of stuff, Like how how well 0:07:35.480 --> 0:07:39.120 is this one cabinet gonna sell compared to this other cabinet, 0:07:39.640 --> 0:07:42.880 both of which have Norwegian or Danish or Swedish or 0:07:42.960 --> 0:07:47.160 Swiss or some Scandinavian name that has far more oom 0:07:47.160 --> 0:07:52.160 louds than is remotely necessary. Um, how well is that 0:07:52.200 --> 0:07:54.720 going to sell versus any other one? You have to 0:07:54.960 --> 0:07:58.120 keep enough in stock so that you meet whatever demands 0:07:58.160 --> 0:08:00.480 you expect there to be, but there's no way of 0:08:00.560 --> 0:08:03.960 knowing from one day to the next how popular an 0:08:04.000 --> 0:08:05.560 item is going to be, even if you put one 0:08:05.560 --> 0:08:09.280 on sale and one's not on sale. Three D printers, however, 0:08:09.280 --> 0:08:11.120 can let you get around that. You don't have to 0:08:11.200 --> 0:08:14.840 have a huge warehouse to store all of your inventory. 0:08:15.240 --> 0:08:18.480 You can have essentially a storage space for the raw 0:08:18.560 --> 0:08:22.560 material for your printer, and then you create the items 0:08:22.640 --> 0:08:25.800 on demand when you get in order. So if someone 0:08:25.880 --> 0:08:28.040 wants a particular cabinet, you print out the parts and 0:08:28.080 --> 0:08:32.719 then sell the kit to the customer. You don't have 0:08:32.800 --> 0:08:36.040 to keep eight different types of cabinets and storage. You 0:08:36.120 --> 0:08:38.920 just keep the digital plans and you print them as needed. 0:08:39.320 --> 0:08:42.160 I think that's gonna be a very popular business model 0:08:42.360 --> 0:08:45.400 once we get to a point where these printers that 0:08:45.480 --> 0:08:49.960 are are ready for commercial use like that fall into 0:08:50.000 --> 0:08:52.880 the range that a small business can can actually make 0:08:52.920 --> 0:08:55.680 that a workable business model. It's pretty expensive if you 0:08:55.720 --> 0:08:59.040 want a really high quality three D printer, especially one 0:08:59.080 --> 0:09:02.240 that can produced on an industrial level, even a small 0:09:02.320 --> 0:09:06.959 industrial level, asked for things like Kinko's. I think that's 0:09:06.960 --> 0:09:09.520 gonna take more time. Uh. And I think there's gonna 0:09:09.520 --> 0:09:14.120 be some barriers as well, because obviously, you if you 0:09:14.200 --> 0:09:17.200 are a business like Kinkos, you want to be able 0:09:17.240 --> 0:09:19.600 to have at least some control over what is getting 0:09:19.679 --> 0:09:23.400 sent to that three D printer. Uh. If it's something 0:09:23.440 --> 0:09:27.240 that is illegal, for example, or the legality is questionable, 0:09:27.360 --> 0:09:31.560 for example, a three D printed gun. That's that could 0:09:31.600 --> 0:09:36.800 be a concern, especially if there were any crime associated 0:09:36.800 --> 0:09:39.120 with that weapon down the line, and it gets brought 0:09:39.160 --> 0:09:42.000 in that your establishment was the one that allowed it 0:09:42.040 --> 0:09:45.120 to be printed. There could be some legal complications that. 0:09:45.200 --> 0:09:48.360 I bet a lot of the big companies don't want 0:09:48.400 --> 0:09:52.200 to get bogged down in and it may be that 0:09:52.280 --> 0:09:57.480 eventually things work out where the accountability lies with other 0:09:57.760 --> 0:10:00.800 other players and not the company that act is housing 0:10:00.840 --> 0:10:03.360 the three D printer, in which case you know it 0:10:03.400 --> 0:10:06.439 may be open season. No pun intended with the gun 0:10:06.480 --> 0:10:10.760 thing to allow everyone to send whatever they want to 0:10:10.800 --> 0:10:13.320 the printer, and as long as they're paying the rate 0:10:13.400 --> 0:10:17.400 for however much plastic is going through the extruder, they're fine. 0:10:18.320 --> 0:10:22.200 So I think we'll see the fabrication on demand model first. 0:10:23.559 --> 0:10:25.640 Of course, three D printers are already being used in 0:10:25.720 --> 0:10:30.199 research and development as well as in manufacturing for other reasons. 0:10:30.200 --> 0:10:33.640 But but the as far as customers getting access to 0:10:33.679 --> 0:10:36.560 three D printers, I think it will be fabrication on demand, 0:10:36.640 --> 0:10:40.920 where the company will be the one responsible for sending 0:10:41.000 --> 0:10:44.559 the specific plan to the specific printer, and the customer 0:10:44.600 --> 0:10:47.320 only says okay, I want this item, so they don't 0:10:47.320 --> 0:10:50.520 get to say exactly what gets printed. And then maybe 0:10:50.520 --> 0:10:53.559 a couple of years later we'll see models where people 0:10:53.600 --> 0:10:57.240 can send their their digital file to a printer directly 0:10:57.440 --> 0:11:01.120 without having to just choose from a catalog of files. 0:11:01.840 --> 0:11:04.400 Um In the meantime, you know there will be plenty 0:11:04.400 --> 0:11:05.840 of people who will just go out and buy their 0:11:05.840 --> 0:11:09.280 own three D printer. Depending upon how much money they spend, 0:11:10.280 --> 0:11:12.800 the stuff they print may or may not look really great, 0:11:13.480 --> 0:11:16.160 or it may look kind of clunky. I've seen some 0:11:16.280 --> 0:11:21.080 three D printers where the the fidelity, the resolution is 0:11:21.280 --> 0:11:26.480 incredible and you you can feel the edges of each layer, 0:11:27.000 --> 0:11:29.360 but you can't really see them easily. And then I've 0:11:29.360 --> 0:11:33.000 seen other ones where it's very apparent where each layer 0:11:33.120 --> 0:11:36.040 is kind of overhanging the next layer by you know, 0:11:36.120 --> 0:11:39.679 a millimeter or whatever, and it's very noticeable. Uh So 0:11:39.840 --> 0:11:43.000 we'll see. Maybe I'm wrong about that, but I suspect not. 0:11:43.600 --> 0:11:47.160 All right, we'll go to the next question. Nathaniel from 0:11:47.160 --> 0:11:50.880 Twitter asked how track pads register input. How does a 0:11:50.960 --> 0:11:54.120 track pad know where your finger is? There are two 0:11:54.240 --> 0:11:59.559 main ways that track pads are manufactured. There are resistive 0:11:59.600 --> 0:12:03.800 track pads and capacitive track pads or touch pads. And 0:12:03.920 --> 0:12:05.880 I know I've talked about this on the show before, 0:12:05.960 --> 0:12:08.560 but it you know, I'll go ahead and explain how 0:12:08.600 --> 0:12:12.520 these work because I think it is interesting. So the 0:12:12.600 --> 0:12:16.120 resist of touch pads or track pads are the easiest 0:12:16.160 --> 0:12:22.520 to understand. Um they're also not as not necessarily as 0:12:23.720 --> 0:12:27.280 resilient as capacity, but we'll get there. So resistive touch 0:12:27.320 --> 0:12:33.679 pads use a couple of different films with kind of 0:12:33.720 --> 0:12:38.320 a uh electrodes. Well, one film will have an electrode 0:12:38.320 --> 0:12:41.480 on it, uh, the next film like a sandwich filling 0:12:41.840 --> 0:12:46.559 that one would be uh somewhat resistive, and then you 0:12:46.600 --> 0:12:49.960 would have a bottom plate that would also have an 0:12:49.960 --> 0:12:54.360 electrode on it. So you've got electrodes separated by a 0:12:54.400 --> 0:13:00.400 resistive film. When you press down on the surface of 0:13:00.480 --> 0:13:06.680 the top layer, it presses that electrode closer to the 0:13:06.760 --> 0:13:10.559 other electrode on the bottom and you end up creating 0:13:10.640 --> 0:13:14.880 essentially a circuit. There is a connection there. And if 0:13:14.920 --> 0:13:18.920 you think about the two films as as sort of wires, 0:13:19.240 --> 0:13:21.959 right like, you have a series of horizontal wires along 0:13:22.000 --> 0:13:26.640 one film and vertical wires along the other electrode. Then 0:13:26.679 --> 0:13:29.440 you've got a grid. So imagine you've got this grid there. 0:13:30.559 --> 0:13:34.240 When you put pressure on the touch pad, it acts 0:13:34.280 --> 0:13:38.080 like these It pushes these these two wires together at 0:13:38.200 --> 0:13:41.600 some point on that grid, and by locating the the 0:13:41.840 --> 0:13:48.000 area of connection along that grid, a computer knows, oh, 0:13:48.200 --> 0:13:50.960 there has been a touch registered at this point on 0:13:51.080 --> 0:13:53.920 the touch pad. So um, you know, it's almost like 0:13:53.920 --> 0:13:56.640 a spider web, right, So you've got this this grid 0:13:56.800 --> 0:14:00.600 of connections and when you press down, it sends the signal, 0:14:01.320 --> 0:14:05.040 and by measuring that signal, the computer can tell where 0:14:05.080 --> 0:14:09.400 along the touchpad you are touching. Capacity is a little different, 0:14:09.800 --> 0:14:12.280 so instead of instead of it being the series of 0:14:12.320 --> 0:14:16.120 wires and the physical connection is what indicates where there's 0:14:16.120 --> 0:14:21.360 a touch, Capacity creates an electric field when your finger 0:14:21.760 --> 0:14:26.560 encounters that electric field. Really, any capacitive or conductive surface 0:14:26.640 --> 0:14:29.720 I should say, not capacity, but a conductive surface, it 0:14:29.880 --> 0:14:35.840 alters that electric field, and sensors inside the device can 0:14:35.920 --> 0:14:41.400 detect where that that point of contact is based upon 0:14:41.480 --> 0:14:45.000 the change of the electric field itself. Now, this is 0:14:45.080 --> 0:14:49.480 why if you use gloves that don't have a conductive 0:14:49.640 --> 0:14:51.880 surface on them, so they don't have like conductive thread 0:14:51.960 --> 0:14:55.800 woven into them or anything, it's very difficult to get 0:14:55.840 --> 0:14:59.120 a capacitive touchscreen to work because you're you don't have 0:14:59.160 --> 0:15:03.400 a conductive urface interfering with that electric field. Generally speaking, 0:15:03.440 --> 0:15:06.600 gloves don't tend to be conductive unless again, you have 0:15:06.680 --> 0:15:10.000 that conductive thread woven into them. It's also why I 0:15:10.040 --> 0:15:13.760 remember a story from several years ago that people. I 0:15:13.760 --> 0:15:15.760 want to say it was in Japan, we're starting to 0:15:15.880 --> 0:15:19.400 use hot dogs as a stylus for their smartphones when 0:15:19.400 --> 0:15:22.280 it would get cold, so they would have gloves and 0:15:22.360 --> 0:15:25.040 use a hot dog, which would be conductive if they 0:15:25.040 --> 0:15:30.360 would use that to make selections and commands on their phones. Um. 0:15:30.480 --> 0:15:34.000 So with the resistive approach, it's all dependent upon pressure 0:15:34.560 --> 0:15:37.000 you have to press, and if you're not pressing hard 0:15:37.080 --> 0:15:39.280 enough to make the contact with those wires, then it 0:15:39.320 --> 0:15:42.680 won't be registered. With the capacity of it's not dependent 0:15:42.760 --> 0:15:45.360 upon pressure. You don't need to push harder to make 0:15:45.400 --> 0:15:49.080 a stronger electric field, although it may by pressing harder 0:15:49.240 --> 0:15:52.920 indicate a larger surface area coming into contact with the screen, 0:15:52.960 --> 0:15:55.680 which you know, you could design a program that would 0:15:55.680 --> 0:15:59.080 react differently depending upon how much pressure was applied, simply 0:15:59.120 --> 0:16:03.560 by many sharing how much surface areas being affected. Ah. 0:16:04.000 --> 0:16:06.280 The problem with the resilience that was talking about earlier 0:16:06.280 --> 0:16:10.440 is that, at least with earlier resistive touch pads, the 0:16:10.520 --> 0:16:13.400 more you would move around, the more you would use it, 0:16:13.560 --> 0:16:16.280 the more it would start to wear down, and over 0:16:16.360 --> 0:16:19.800 time your touch pad would become less responsive because it 0:16:19.880 --> 0:16:25.280 was starting to just wear away from use. Whereas capacitive ones. 0:16:25.480 --> 0:16:27.920 You know, you don't have to have this hard contact 0:16:28.160 --> 0:16:30.720 to make sure that it's registering a touch, and they 0:16:30.720 --> 0:16:34.880 could last longer for a while. Capacity of touch pads 0:16:34.880 --> 0:16:39.240 were much more expensive than resistive, so resistive we're very popular, 0:16:39.320 --> 0:16:42.680 particularly in industrial uses where you might have like a 0:16:42.720 --> 0:16:45.840 tablet that has a resistive screen and it's meant for 0:16:45.920 --> 0:16:49.040 heavy duty use. There's no point in making it delicate 0:16:49.040 --> 0:16:51.760 because it was going to be in a tough environment anyway, 0:16:52.280 --> 0:16:55.760 and resistive was really popular. These days, the difference in 0:16:55.840 --> 0:16:59.280 price is not as great, so we mostly see capacity 0:16:59.280 --> 0:17:02.320 of screens but reicularly in things like smartphones and tablets. 0:17:02.520 --> 0:17:13.280 So I hope that answers that question. All right, let's 0:17:13.280 --> 0:17:18.240 move on to the next email. This one comes from 0:17:18.280 --> 0:17:20.760 Greg and says, Hey, Jonathan, I enjoy your show Tech 0:17:20.840 --> 0:17:24.640 Stuff and forward Thinking a lot. Y'all are some real 0:17:24.760 --> 0:17:28.040 gangster's thanks. I don't really think of myself as gangster. 0:17:28.240 --> 0:17:30.360 That's that's a new one for me. So you did 0:17:30.400 --> 0:17:34.080 an episode on TV Connectors recently and mentioned impedance gain 0:17:34.200 --> 0:17:37.400 and attenuation and then said that could be its own podcast. 0:17:37.440 --> 0:17:39.320 So I'd love to hear a podcast about those topics. 0:17:39.359 --> 0:17:43.440 Maybe also explain decibels as well. All right, Greg, here goes. 0:17:43.880 --> 0:17:46.840 This is gonna be an attempt on my part to 0:17:46.880 --> 0:17:50.280 explain these concepts. First of all, I gotta come clean, 0:17:50.320 --> 0:17:54.320 because you know, have you ever had that experience where 0:17:54.359 --> 0:17:56.119 you encounter a word and you have to say the 0:17:56.160 --> 0:18:00.000 word out loud, and then you realize as you're about 0:18:00.040 --> 0:18:01.760 to say the word out loud that you have never 0:18:01.840 --> 0:18:05.280 really heard that word spoken before, or if you had, 0:18:05.480 --> 0:18:08.199 you hadn't really paid attention, and so you just have 0:18:08.280 --> 0:18:11.840 to give a wild guess as to how it's pronounced, 0:18:12.160 --> 0:18:15.840 and then you guess wrong. Because that is exactly what 0:18:15.880 --> 0:18:17.880 happened to me the last time I talked about impedance. 0:18:18.520 --> 0:18:23.160 I believe I meant I pronounced it impedence, which, while hilarious, 0:18:23.520 --> 0:18:26.800 is not correct. So if any of my listeners out 0:18:26.840 --> 0:18:31.399 there tried to follow my lead and found themselves in 0:18:31.480 --> 0:18:37.240 socially awkward situations because of their pronunciation, I humbly apologize, Um, 0:18:37.280 --> 0:18:39.320 but no, that was definitely one of those cases where 0:18:39.600 --> 0:18:41.280 in my brain I'm like, oh, it has to be 0:18:41.720 --> 0:18:45.440 spelled like are pronounced like this because the way it's spelled, 0:18:45.800 --> 0:18:47.879 and I was absolutely wrong. And in fact, if I 0:18:47.880 --> 0:18:50.679 had thought about it for a second, I would have 0:18:50.800 --> 0:18:55.240 realized how wrong I was, because it's about impeding. It's 0:18:55.400 --> 0:18:59.920 impedence because it impedes the flow of electricity. But I'm 0:19:00.000 --> 0:19:04.160 getting ahead of myself. So when when we talk about impedance, 0:19:04.200 --> 0:19:07.760 we need to first talk about voltage. And for those 0:19:07.760 --> 0:19:10.159 of you who have taken physics and you know all 0:19:10.200 --> 0:19:16.159 about circuitry and voltage and current uh and resistance, I apologize, 0:19:16.160 --> 0:19:18.240 But in order to explain impedance, I kind of have 0:19:18.320 --> 0:19:20.720 to lay some groundwork, So just stick with me here. 0:19:21.240 --> 0:19:25.840 Voltage is the difference in electrical energy charge of electrical 0:19:25.880 --> 0:19:30.760 potential energy between two points. Uh. And that sounds weird, 0:19:31.160 --> 0:19:33.280 but another way to look at is that voltage is 0:19:33.320 --> 0:19:37.240 how we describe an electric field. We measure electric fields 0:19:37.240 --> 0:19:41.159 and volts over a distance, so you have to have 0:19:41.200 --> 0:19:43.560 a difference in voltage in order for current to flow. 0:19:44.080 --> 0:19:46.240 Another way of thinking that is you need to have 0:19:47.119 --> 0:19:49.960 an excess of electrons on one side of your circuit 0:19:50.200 --> 0:19:53.120 and a place for electrons to go on the other 0:19:53.160 --> 0:19:56.000 side of your circuit, and that is a difference in voltage. 0:19:56.000 --> 0:19:58.040 You have a positive charge on one side and a 0:19:58.040 --> 0:20:01.080 negative charge on the other. And that allows the electrons 0:20:01.119 --> 0:20:04.399 to move from negative to positive. We won't go into 0:20:04.480 --> 0:20:06.800 the difference between the flow of electrons and the flow 0:20:06.840 --> 0:20:08.919 of current here. I know I've talked about that in 0:20:08.960 --> 0:20:11.440 previous episodes of tech Stuff, and it's not really relevant 0:20:11.440 --> 0:20:14.480 in this case. You just need to know that voltage 0:20:14.600 --> 0:20:19.200 is this difference in electric charge and electric potential energy 0:20:19.200 --> 0:20:23.960 between two points across some distance. When you apply voltage 0:20:24.000 --> 0:20:27.200 to a circuit, that's when you induce electricity to flow 0:20:27.440 --> 0:20:30.359 through that circuit. Now, the circuit is made of some 0:20:30.440 --> 0:20:34.879 sort of conductive material. Now, conductive material doesn't allow electricity 0:20:34.920 --> 0:20:38.879 to flow through effortlessly. There's an opposition to the flow 0:20:39.000 --> 0:20:43.199 of electricity, and it's called resistance. And resistance depends upon 0:20:43.280 --> 0:20:47.639 a couple of different factors um well several. Actually, it 0:20:47.680 --> 0:20:51.000 depends upon the material. It depends upon how much the 0:20:51.040 --> 0:20:52.720 material is there. In other words, if you have a 0:20:52.800 --> 0:20:56.840 very small copper wire that actually has a much higher 0:20:56.880 --> 0:21:01.320 resistance than say, very thick copper cable. It also depends 0:21:01.359 --> 0:21:06.840 upon temperature. You know, super cooling semiconductors can reduce the 0:21:06.960 --> 0:21:11.560 resistance to near zero or effectively zero, and you get 0:21:12.119 --> 0:21:15.920 you know, free and clear electricity. Flowing through without any resistance, 0:21:15.920 --> 0:21:19.320 and you know, otherwise what happens is the opposition to 0:21:19.400 --> 0:21:23.359 that electrical flow will end up having you uh, you know, 0:21:23.680 --> 0:21:26.399 the component will actually start to generate heat. And this 0:21:26.440 --> 0:21:29.919 is where we talk about how efficient and electronic devices. 0:21:30.760 --> 0:21:32.639 If it's generating a lot of heat, you're losing a 0:21:32.720 --> 0:21:36.240 lot of energy to heat. That electricity is being converted 0:21:36.280 --> 0:21:39.639 into heat energy and not doing whatever it was you 0:21:39.680 --> 0:21:41.760 were hoping for it to do, unless, of course, it 0:21:41.840 --> 0:21:43.920 was a heating component, in which case it's doing exactly 0:21:43.960 --> 0:21:49.320 what you wanted it to do. So that's resistance. Now. 0:21:49.840 --> 0:21:53.800 In direct current circuits, resistance suffices as the term we 0:21:53.920 --> 0:21:58.880 use for this phenomenon. But with alternating current a C applications, 0:21:59.280 --> 0:22:02.760 these are different because the current alternates. It flows in 0:22:02.800 --> 0:22:06.960 one direction the circuit and then flows in the opposite direction. Uh. 0:22:06.960 --> 0:22:10.200 And it does this in cycles different frequencies that will 0:22:10.680 --> 0:22:14.239 usually it's in a single frequency, but the frequencies can 0:22:14.320 --> 0:22:17.919 vary depending upon the technology we're talking about. So in 0:22:17.960 --> 0:22:21.520 this case we don't use the term resistance. We actually 0:22:21.600 --> 0:22:26.120 use a different term, and that is impedance because uh, 0:22:26.200 --> 0:22:31.240 impedance relies on two factors, not just the magnitude, which 0:22:31.440 --> 0:22:34.080 is pretty much what resistance is considered concerned with, but 0:22:34.160 --> 0:22:39.240 the phase of the of the system as well. UH 0:22:39.440 --> 0:22:44.360 So impedance impedes the flow of electricity, but it consists 0:22:44.400 --> 0:22:47.840 of reactants as well as resistance, and reactance is the 0:22:47.880 --> 0:22:52.320 extent to which a circuit stores and releases energy as 0:22:52.359 --> 0:22:57.600 the current and voltage fluctuate with each alternating current cycle. 0:22:58.520 --> 0:23:01.399 So we describe reactance in terms terms of ohms, and 0:23:01.440 --> 0:23:05.399 it really only applies to a C circuits. Reactance allows 0:23:05.440 --> 0:23:08.640 us to use circuit components such as capacitors and inductors. 0:23:08.840 --> 0:23:13.040 Capacitors store energy in an electric field and inductor's store 0:23:13.160 --> 0:23:17.160 energy in a magnetic field, and both can operate as 0:23:17.200 --> 0:23:20.080 resistors and they don't generate heat the same way that 0:23:20.119 --> 0:23:23.800 resistors do, so they're very useful in a C circuitry. 0:23:24.359 --> 0:23:28.320 So that's impedance. Uh it's an important factor whenever you're 0:23:28.359 --> 0:23:31.720 designing any kind of electronic component that has that's working 0:23:31.800 --> 0:23:34.600 on a C. Next, we have gain, which is the 0:23:34.600 --> 0:23:37.919 next thing that that Greg asked us about. This is 0:23:38.000 --> 0:23:42.359 also known as the amplification factor, and it gives you 0:23:42.400 --> 0:23:44.920 some clue as to what's going on with gain. It's 0:23:44.960 --> 0:23:48.280 all about amplifying a signal to boost its strength from 0:23:48.400 --> 0:23:52.720 input to output. So you've got an incoming signal, then 0:23:52.760 --> 0:23:56.240 you use a means of amplification to increase the strength 0:23:56.359 --> 0:23:59.919 of that signal, so it's the same frequency but greater amplitude, 0:24:00.680 --> 0:24:02.919 and then you put it through the output. This is 0:24:03.000 --> 0:24:05.840 used in all sorts of applications. The easiest one to 0:24:05.960 --> 0:24:12.040 imagine happens to be sound, where a microphone will convert 0:24:12.160 --> 0:24:16.840 acoustic waves into electrical impulses that then will go to 0:24:17.240 --> 0:24:20.600 a an amplifier before going to a speaker in order 0:24:20.600 --> 0:24:23.359 to strengthen the signals so that you can get an 0:24:23.400 --> 0:24:26.400