1 00:00:00,320 --> 00:00:02,880 Speaker 1: Brought to you by the reinvented two thousand twelve camera. 2 00:00:03,240 --> 00:00:08,959 Speaker 1: It's ready. Are you get in touch with technology with 3 00:00:09,039 --> 00:00:17,720 Speaker 1: tech stuff from how stuff works dot com. Hello, everyone, 4 00:00:17,760 --> 00:00:20,479 Speaker 1: welcome to tech stuff. My name is Chris Poulette and 5 00:00:20,520 --> 00:00:23,080 Speaker 1: I am an editor at how stuff works dot com. 6 00:00:23,079 --> 00:00:26,800 Speaker 1: Sitting across from me is senior writer Jonathan Strickland. I 7 00:00:26,880 --> 00:00:30,040 Speaker 1: hear that train of coming. It's coming around the bend. 8 00:00:31,680 --> 00:00:35,440 Speaker 1: So did you engineer that quote? No, actually I did 9 00:00:35,440 --> 00:00:39,120 Speaker 1: not engineer that. That was That was something conducted by 10 00:00:39,159 --> 00:00:42,479 Speaker 1: someone else. That was such a terrible stretch. But you 11 00:00:42,520 --> 00:00:45,040 Speaker 1: know what, I'm gonna save myself here by going into 12 00:00:45,080 --> 00:00:53,320 Speaker 1: a little listener mail. This listener mail comes from Weston, 13 00:00:53,360 --> 00:00:56,280 Speaker 1: who says, Hi, my name is Weston. Well I know Weston. 14 00:00:56,320 --> 00:00:59,360 Speaker 1: I just said that I'm from South Carolina and looking 15 00:00:59,400 --> 00:01:02,279 Speaker 1: through your white extensive list of podcasts, I could not 16 00:01:02,400 --> 00:01:06,039 Speaker 1: find one that involved how railroad crossing signals work. So 17 00:01:06,080 --> 00:01:07,959 Speaker 1: I was wondering if you could explain that, and if 18 00:01:07,959 --> 00:01:10,760 Speaker 1: you could explain how railroad crossing systems tie into traffic 19 00:01:10,760 --> 00:01:13,960 Speaker 1: signals in more urban districts. Thanks a lot, keep doing 20 00:01:14,000 --> 00:01:17,560 Speaker 1: your thing. Well, thanks Weston. Yes it is true. We 21 00:01:17,680 --> 00:01:21,920 Speaker 1: had not done a podcast on railroad crossing signals. Uh, 22 00:01:22,800 --> 00:01:25,760 Speaker 1: it just never honestly occurred to me, and in fact, 23 00:01:25,880 --> 00:01:29,759 Speaker 1: until I started researching this, I had no idea how 24 00:01:29,800 --> 00:01:33,959 Speaker 1: complicated it really was. That's true, although they have changed 25 00:01:34,000 --> 00:01:36,480 Speaker 1: over the years too to some degree. Yeah, it used 26 00:01:36,480 --> 00:01:39,360 Speaker 1: to be that the railroad crossing signal was that the 27 00:01:39,480 --> 00:01:42,319 Speaker 1: train in very busy areas, the train would come to 28 00:01:42,360 --> 00:01:45,920 Speaker 1: a stop. A flag man would go to the crossing 29 00:01:45,959 --> 00:01:49,640 Speaker 1: area and and manually stop traffic for the train to 30 00:01:49,640 --> 00:01:53,360 Speaker 1: pass through, and then would go jog get back on 31 00:01:53,400 --> 00:01:55,520 Speaker 1: the train and then everything would start up again. So 32 00:01:55,560 --> 00:02:00,120 Speaker 1: that's about you know, that's pretty simple technology. Yeah, have 33 00:02:00,160 --> 00:02:02,440 Speaker 1: to agree that that's uh well, there's not a lot 34 00:02:02,480 --> 00:02:05,840 Speaker 1: of electronic technology involved in that. At night, sometimes they'd 35 00:02:05,880 --> 00:02:10,079 Speaker 1: use flares. I've actually seen that. I've there was a 36 00:02:10,160 --> 00:02:14,280 Speaker 1: rural crossing, a railroad crossing in northern Georgia, which is 37 00:02:14,320 --> 00:02:16,720 Speaker 1: where I grew up. What you can tell because of 38 00:02:16,760 --> 00:02:21,160 Speaker 1: my deep Southern accent, But in in rural Georgia there 39 00:02:21,240 --> 00:02:23,920 Speaker 1: was a crossing at one point. I remember as a 40 00:02:24,000 --> 00:02:25,760 Speaker 1: kid we came up to it, and I think the 41 00:02:25,800 --> 00:02:30,040 Speaker 1: reason for using the flares was not because there was 42 00:02:30,080 --> 00:02:34,120 Speaker 1: no modern crossing signal there. I think the modern crossing 43 00:02:34,120 --> 00:02:37,919 Speaker 1: signal was unfortunately out of order, and so they were 44 00:02:38,000 --> 00:02:41,320 Speaker 1: using the flares as a backup system and UH, and 45 00:02:41,440 --> 00:02:43,720 Speaker 1: that's exactly what they did. They stopped the train, a 46 00:02:43,760 --> 00:02:47,320 Speaker 1: guy got out and lit some flares along the side 47 00:02:47,400 --> 00:02:51,200 Speaker 1: of the tracks, and then the train went through and 48 00:02:51,240 --> 00:02:54,359 Speaker 1: we had to wait, and then we drove on by. 49 00:02:54,680 --> 00:02:57,359 Speaker 1: Well then it actually seems like it could be a 50 00:02:57,400 --> 00:02:59,720 Speaker 1: little bit more reliable than some of the technology that 51 00:02:59,800 --> 00:03:03,720 Speaker 1: we we're researching. UM. I have to have to give 52 00:03:03,760 --> 00:03:09,000 Speaker 1: any shout out actually to uh matt Enus who has 53 00:03:09,040 --> 00:03:15,000 Speaker 1: a really awesome website about the electronics behind railroad crossing 54 00:03:15,120 --> 00:03:18,280 Speaker 1: signal technology and it's it's very very through. Apparently he 55 00:03:18,360 --> 00:03:21,239 Speaker 1: really likes electronics and trains, so this was sort of 56 00:03:21,240 --> 00:03:23,600 Speaker 1: a natural for him. Yeah, you can find his his 57 00:03:24,440 --> 00:03:28,160 Speaker 1: website at Matt dot z o n T dot org. 58 00:03:28,960 --> 00:03:31,160 Speaker 1: I thought i'd give a shout out because I also 59 00:03:31,200 --> 00:03:34,200 Speaker 1: found it really helpful. He has lots of of of 60 00:03:34,200 --> 00:03:39,080 Speaker 1: technical drawings for for circuitry as well as some great animations. 61 00:03:39,400 --> 00:03:43,240 Speaker 1: It really makes understanding this UH a lot easier, although 62 00:03:43,280 --> 00:03:46,560 Speaker 1: again it's still a very when you get if you 63 00:03:46,600 --> 00:03:50,640 Speaker 1: really dig down, it's still really complicated. Well A said it. 64 00:03:50,680 --> 00:03:53,320 Speaker 1: As it turns out, just about every type of signal 65 00:03:54,080 --> 00:03:59,320 Speaker 1: UH crossing signal uses some form of an electronic relay 66 00:03:59,880 --> 00:04:02,880 Speaker 1: or I should say electrical relay. Um. And a lot 67 00:04:02,880 --> 00:04:06,520 Speaker 1: of it has to do with basically detecting that a 68 00:04:06,600 --> 00:04:10,480 Speaker 1: train is coming. Now it's not necessarily from a distance. 69 00:04:10,840 --> 00:04:13,119 Speaker 1: In a lot of cases, it's basically when it's right 70 00:04:13,200 --> 00:04:16,599 Speaker 1: on top of the crossing, not literally right now, when 71 00:04:16,760 --> 00:04:19,520 Speaker 1: when it's right there at the crossing before it gets 72 00:04:19,560 --> 00:04:22,600 Speaker 1: to the uh for it actually gets to the intersection 73 00:04:22,640 --> 00:04:26,480 Speaker 1: with a roadway. Yeah. Yeah, so there are some there 74 00:04:26,480 --> 00:04:29,200 Speaker 1: are lots of different types of these these systems, we 75 00:04:29,240 --> 00:04:32,640 Speaker 1: should say, because first of all, uh, it's it's easy 76 00:04:32,720 --> 00:04:37,880 Speaker 1: to forget that the railroad system is not a unified 77 00:04:38,120 --> 00:04:41,960 Speaker 1: thing overseen by a single entity. No, that's correct. There 78 00:04:42,000 --> 00:04:46,320 Speaker 1: are several railroad systems throughout the United States alone, and 79 00:04:46,360 --> 00:04:47,960 Speaker 1: you know that's just the United States where you know, 80 00:04:48,240 --> 00:04:50,640 Speaker 1: it gets way more complicated when you're looking at things 81 00:04:50,680 --> 00:04:54,039 Speaker 1: like international railroad systems that go through most of Europe 82 00:04:54,160 --> 00:04:57,960 Speaker 1: for example. UM. So, because there are all these different 83 00:04:58,040 --> 00:05:00,000 Speaker 1: entities that are running the railroads, I mean there are 84 00:05:00,000 --> 00:05:04,560 Speaker 1: are certain standards, like railroads are railroad rails are at 85 00:05:04,600 --> 00:05:08,640 Speaker 1: a standard with where else your trains cannot go from 86 00:05:08,640 --> 00:05:13,599 Speaker 1: one system to another. But things like the signaling systems 87 00:05:13,640 --> 00:05:17,840 Speaker 1: the electronics they use are not necessarily standard across the board. 88 00:05:17,839 --> 00:05:20,200 Speaker 1: They're all supposed to operate in a standard way, but 89 00:05:20,640 --> 00:05:23,760 Speaker 1: the way you get there is not necessarily standard. If 90 00:05:23,760 --> 00:05:26,560 Speaker 1: that makes sense. Well, what I thought we might do 91 00:05:26,680 --> 00:05:29,520 Speaker 1: is actually talk about the signals themselves, and then we 92 00:05:29,520 --> 00:05:33,440 Speaker 1: could talk about the way that they're triggered me because um, 93 00:05:33,720 --> 00:05:37,160 Speaker 1: you know, and at a given intersection. Actually, that's that's 94 00:05:37,240 --> 00:05:39,599 Speaker 1: another good point back to what you just said, was 95 00:05:40,200 --> 00:05:45,160 Speaker 1: um that not every signal, uh, not every crossing has 96 00:05:45,200 --> 00:05:49,200 Speaker 1: the same types of signals either, even on the same uh, 97 00:05:49,279 --> 00:05:52,280 Speaker 1: even on the same railroad. So you know a lot 98 00:05:52,320 --> 00:05:54,840 Speaker 1: of times you'll see you know, the signal mast, which 99 00:05:54,880 --> 00:05:57,479 Speaker 1: is that poll with the lights on either side of it. Hum. 100 00:05:57,520 --> 00:06:01,680 Speaker 1: And basically this is just a current flowing through, just 101 00:06:01,760 --> 00:06:04,560 Speaker 1: like you would with a typical light bulb. Um, but 102 00:06:04,760 --> 00:06:09,080 Speaker 1: it's it's got a relay, a flasher relay between that 103 00:06:09,240 --> 00:06:12,000 Speaker 1: basically alternates the circuits. So one light goes on the 104 00:06:12,040 --> 00:06:14,200 Speaker 1: other one goes off. Then they switch back and forth, 105 00:06:14,240 --> 00:06:15,960 Speaker 1: back and forth. Yeah, I think it pretty easy. Think 106 00:06:15,960 --> 00:06:18,279 Speaker 1: of the flasher relay is kind of like a switch 107 00:06:18,960 --> 00:06:21,360 Speaker 1: that opens and closes, but when it when it when 108 00:06:21,400 --> 00:06:24,040 Speaker 1: it opens for one side, it's closed for the other 109 00:06:24,120 --> 00:06:27,240 Speaker 1: and vice versa. So as long as power is running 110 00:06:27,240 --> 00:06:29,720 Speaker 1: through this, one side of the lights will light up 111 00:06:29,760 --> 00:06:32,640 Speaker 1: and the other side will remain dark. And it alternates, 112 00:06:32,640 --> 00:06:36,120 Speaker 1: and that's what creates the flashing pattern. And they alternated. 113 00:06:36,360 --> 00:06:39,480 Speaker 1: There's one way that it can be alternated. Again. There 114 00:06:39,480 --> 00:06:42,560 Speaker 1: are lots of systems, but one way that they can 115 00:06:42,600 --> 00:06:47,120 Speaker 1: alternate is through using electromagnets. Our old friend, the electromagnets, right, 116 00:06:47,200 --> 00:06:51,680 Speaker 1: So the electro magnets will have a set of coils 117 00:06:51,680 --> 00:06:54,320 Speaker 1: on either side, and when one set of coils gets power, 118 00:06:54,760 --> 00:06:57,960 Speaker 1: that pulls the switch to that side and creates a 119 00:06:58,000 --> 00:07:01,159 Speaker 1: magnetic field which pulls the switch her. That's what lights 120 00:07:01,240 --> 00:07:04,640 Speaker 1: up the lights on one side, and then the other 121 00:07:04,680 --> 00:07:06,760 Speaker 1: set of coils will get power. The first set will 122 00:07:06,760 --> 00:07:09,679 Speaker 1: lose power, so now the switch will be pulled back 123 00:07:09,760 --> 00:07:11,720 Speaker 1: to the other side, which will light up the other 124 00:07:11,760 --> 00:07:14,400 Speaker 1: side of the lights. And alternating this back and forth 125 00:07:14,520 --> 00:07:17,160 Speaker 1: is what gives you that click click click click as 126 00:07:17,200 --> 00:07:21,360 Speaker 1: the as the flashers go on and off. Uh. I 127 00:07:21,400 --> 00:07:26,080 Speaker 1: will have to say, though, that this behavior changes dramatically 128 00:07:26,200 --> 00:07:30,360 Speaker 1: if you happen to be within a certain distance of UFOs, 129 00:07:31,160 --> 00:07:36,720 Speaker 1: as seen in the documentary but nothing but Close Encounters 130 00:07:36,720 --> 00:07:38,560 Speaker 1: of the Third Kind? Man, did you not watch it? 131 00:07:38,600 --> 00:07:42,080 Speaker 1: I mean those lights went crazy. This means something, This 132 00:07:42,160 --> 00:07:45,680 Speaker 1: is important. Okay, that was That was clearly a joke. 133 00:07:45,720 --> 00:07:48,960 Speaker 1: I was referencing a Spielberg movie, Close Encounters of the 134 00:07:48,960 --> 00:07:52,080 Speaker 1: Third Kind. I do not, in fact believe that aliens 135 00:07:52,120 --> 00:07:55,680 Speaker 1: affect our railroad crossings at some too busy messine with 136 00:07:55,720 --> 00:07:59,280 Speaker 1: our fast food restaurants. At some point we should uh 137 00:07:59,600 --> 00:08:03,720 Speaker 1: do a podcast on why every time aliens come down 138 00:08:04,120 --> 00:08:09,720 Speaker 1: your radio dial changes and the rail road You're always 139 00:08:09,760 --> 00:08:13,120 Speaker 1: near a railroad. You know what drives me stuff podcast? 140 00:08:13,120 --> 00:08:15,520 Speaker 1: I'm listening to the radio and next thing, you know, 141 00:08:15,600 --> 00:08:18,160 Speaker 1: aliens come down and it switches the golden oldies. I 142 00:08:18,200 --> 00:08:21,720 Speaker 1: just hate that. Um And we got a little off 143 00:08:21,880 --> 00:08:27,560 Speaker 1: track on our railroad podcast speaking speaking of electromagnets, so 144 00:08:27,640 --> 00:08:31,400 Speaker 1: that the same the same uh things sort of applies 145 00:08:31,440 --> 00:08:34,640 Speaker 1: to the bell. The bell that goes clian client client clang, 146 00:08:34,679 --> 00:08:37,840 Speaker 1: that tells you that's going on, except, um, what's going 147 00:08:37,920 --> 00:08:41,680 Speaker 1: on there is the electromagnet is pushing the clapper to 148 00:08:41,760 --> 00:08:43,400 Speaker 1: the bell. The clapper is the thing. If you're not 149 00:08:43,400 --> 00:08:46,959 Speaker 1: familiar with bell technology, and I'm not talking about mob bell, 150 00:08:47,920 --> 00:08:51,960 Speaker 1: it's got the il communication. Um, you got the clapper 151 00:08:52,040 --> 00:08:54,800 Speaker 1: being pushed to the side of the bell by an electromagnet. 152 00:08:55,040 --> 00:08:56,880 Speaker 1: But the thing is the thing. I thought it was 153 00:08:56,920 --> 00:08:59,560 Speaker 1: cool about this at least according to to Matt's page. 154 00:09:00,120 --> 00:09:02,720 Speaker 1: Is what happens is once the clapper reaches the bell, 155 00:09:02,920 --> 00:09:07,040 Speaker 1: it's breaking the connection uh to the electrone, so it 156 00:09:07,120 --> 00:09:09,760 Speaker 1: pulls it back and it pushes it back again. So 157 00:09:09,800 --> 00:09:12,560 Speaker 1: it's just snapping back and forth. It's the momentum that 158 00:09:12,600 --> 00:09:15,080 Speaker 1: carries it forward so that it actually makes contact with 159 00:09:15,120 --> 00:09:17,560 Speaker 1: the bell. Yes, and then it gets pulled back to 160 00:09:17,600 --> 00:09:20,800 Speaker 1: its original position where again where and then it gets 161 00:09:20,800 --> 00:09:23,680 Speaker 1: pushed again. Yeah and yeah, that's kind of that's pretty neat. 162 00:09:24,240 --> 00:09:26,360 Speaker 1: And of course it's happening at a regular interval because 163 00:09:26,400 --> 00:09:29,240 Speaker 1: of the the length I guess of the piece, the 164 00:09:29,280 --> 00:09:33,480 Speaker 1: physical clapper piece. It's it's a centrical same same principle 165 00:09:33,559 --> 00:09:36,480 Speaker 1: that you'll find on other alarm bells, things like you 166 00:09:36,520 --> 00:09:39,480 Speaker 1: know the classic fire station alarm bell works on the 167 00:09:39,520 --> 00:09:42,840 Speaker 1: same principle. I'm sorry that kind of alarms me. Yeah, 168 00:09:42,920 --> 00:09:44,680 Speaker 1: well I live right next to a fire station, so 169 00:09:45,720 --> 00:09:51,120 Speaker 1: really familiar with the fire station bell. Okay. So the 170 00:09:51,160 --> 00:09:55,240 Speaker 1: gates that drop down in front of the uh the crossing, 171 00:09:55,280 --> 00:09:58,160 Speaker 1: you know, the red and white bars basically if that, 172 00:09:58,360 --> 00:10:01,520 Speaker 1: sometimes have lights on them. Sometimes I don't. UM, they 173 00:10:01,640 --> 00:10:04,440 Speaker 1: use a different kind of technology. They actually use a 174 00:10:04,440 --> 00:10:07,600 Speaker 1: motor UM and there's a relay called the motor control 175 00:10:07,600 --> 00:10:12,679 Speaker 1: relay that basically allows the the motor to operate in 176 00:10:12,679 --> 00:10:15,400 Speaker 1: one direction as the gate comes down. So basically it 177 00:10:15,559 --> 00:10:17,600 Speaker 1: is starting to push the gate down and at a 178 00:10:17,600 --> 00:10:19,640 Speaker 1: certain point, of course, you know, there's a weight on 179 00:10:19,640 --> 00:10:22,920 Speaker 1: the other end to counterbalance and um, at a certain 180 00:10:22,920 --> 00:10:26,000 Speaker 1: point the gate would come crashing down, so about midway 181 00:10:26,040 --> 00:10:30,080 Speaker 1: down or so, the relay switches the motor to prevent 182 00:10:30,160 --> 00:10:33,720 Speaker 1: it from the gate from crashing down too quickly. So 183 00:10:33,760 --> 00:10:35,680 Speaker 1: on what you know, at the beginning, it's starting it 184 00:10:35,760 --> 00:10:37,959 Speaker 1: down and then the bottom is like oh okay, okay, okay, 185 00:10:38,000 --> 00:10:40,040 Speaker 1: not too fast, not too fast, all right, there you go. 186 00:10:40,280 --> 00:10:42,920 Speaker 1: So yeah, so in one case it's actually pushing it downward, 187 00:10:42,960 --> 00:10:45,120 Speaker 1: and in the other case, it's pushing upward, but not 188 00:10:45,360 --> 00:10:47,439 Speaker 1: so hard that it makes the gate go right back 189 00:10:47,520 --> 00:10:50,959 Speaker 1: up again, right, and just slows the gates decent. Yeah. 190 00:10:51,160 --> 00:10:53,760 Speaker 1: And and of course there are many ways to achieve 191 00:10:53,840 --> 00:10:56,720 Speaker 1: this effect. Apparently it has to do with the manufacturer 192 00:10:56,760 --> 00:11:00,440 Speaker 1: of the gear. Um, at least according to Matt, it's 193 00:11:00,440 --> 00:11:04,560 Speaker 1: really useful railroad signal technology page. Yeah. And and the 194 00:11:04,600 --> 00:11:07,120 Speaker 1: reason you don't want those gates coming down too quickly, 195 00:11:07,200 --> 00:11:08,920 Speaker 1: I mean, apart from the fact that it's gonna cause 196 00:11:09,000 --> 00:11:11,360 Speaker 1: way too much wear and tear in your equipment, is 197 00:11:11,400 --> 00:11:15,600 Speaker 1: that you don't want to whack cars that are in 198 00:11:15,679 --> 00:11:21,040 Speaker 1: the the the railroad area when the signal is activated. 199 00:11:21,080 --> 00:11:22,400 Speaker 1: You know, you have to have enough time for the 200 00:11:22,440 --> 00:11:26,280 Speaker 1: car to clear. Um. That's also that's really the chief 201 00:11:26,320 --> 00:11:29,240 Speaker 1: reason for the bell. The bell is really there to 202 00:11:29,320 --> 00:11:32,280 Speaker 1: let people know people who are on the tracks at 203 00:11:32,320 --> 00:11:34,640 Speaker 1: that moment as they're crossing over, that hey, there's a 204 00:11:34,679 --> 00:11:38,719 Speaker 1: train in coming, your best get some moving. But that 205 00:11:38,840 --> 00:11:40,720 Speaker 1: they use the bell ringing noise because they found that 206 00:11:40,800 --> 00:11:42,960 Speaker 1: having an old guy send and they're yelling that out 207 00:11:43,040 --> 00:11:47,760 Speaker 1: just wasn't nearly as effective. Yeah. Yeah, it's um one 208 00:11:47,800 --> 00:11:51,240 Speaker 1: of those things that people still try to circumvent quite 209 00:11:51,240 --> 00:11:55,079 Speaker 1: frequently terrible, terrible idea. It's a very very bad idea 210 00:11:55,120 --> 00:11:58,880 Speaker 1: to try to drive around the gates um or you know, 211 00:11:59,520 --> 00:12:01,960 Speaker 1: if you have to be any crossing, like there is 212 00:12:02,040 --> 00:12:06,840 Speaker 1: one near my house, Um, people often go through and 213 00:12:06,880 --> 00:12:09,560 Speaker 1: sit there on the track waiting for the light change. 214 00:12:10,440 --> 00:12:13,360 Speaker 1: And that's just a bad idea. Yeah, you don't want 215 00:12:13,360 --> 00:12:15,480 Speaker 1: to be there. There are stories I could tell, but 216 00:12:15,520 --> 00:12:19,160 Speaker 1: I won't, but yeah, it's just a bad idea. So 217 00:12:19,200 --> 00:12:22,080 Speaker 1: that got that. That covers the UH the basics of 218 00:12:22,120 --> 00:12:26,439 Speaker 1: the arms and the mast, yeah, and the lights that 219 00:12:27,520 --> 00:12:30,880 Speaker 1: in the so and the these this system. By the way, 220 00:12:30,960 --> 00:12:35,040 Speaker 1: you asked Weston specifically about how that works within urban areas. 221 00:12:35,559 --> 00:12:42,760 Speaker 1: The system can be keyed into any adjacent UH traffic signal. Essentially, 222 00:12:42,760 --> 00:12:46,559 Speaker 1: it's just part of that traffic signals cycle. So if 223 00:12:46,600 --> 00:12:52,319 Speaker 1: the traffic signal receives UM signal from the railroad crossing 224 00:12:52,400 --> 00:12:57,160 Speaker 1: its superseds, anything else on that intersection, so instead of 225 00:12:57,160 --> 00:12:59,760 Speaker 1: the lights cycling through as they normally would, it'll be 226 00:13:00,080 --> 00:13:04,440 Speaker 1: stuck on a particular setting. So maybe like the parallel 227 00:13:04,520 --> 00:13:08,120 Speaker 1: road would still get green, but the road that would 228 00:13:08,120 --> 00:13:12,160 Speaker 1: intersect would have a red until the until the signal 229 00:13:12,280 --> 00:13:15,720 Speaker 1: from the railroad crossing gave the all clear. Yes, that's 230 00:13:15,720 --> 00:13:18,559 Speaker 1: that's exactly how it works. At the crossing near my house. 231 00:13:18,679 --> 00:13:22,400 Speaker 1: It blocks out all the traffic that would necessarily cross. 232 00:13:22,440 --> 00:13:26,520 Speaker 1: And the thing is, I've I've seen cars unfortunately who 233 00:13:26,679 --> 00:13:30,080 Speaker 1: uh not unfortunately in the other sense we were speaking 234 00:13:30,080 --> 00:13:32,199 Speaker 1: of earlier, the ones who get there at the red 235 00:13:32,320 --> 00:13:35,600 Speaker 1: light waiting to cross. There's there are basically two sets 236 00:13:35,600 --> 00:13:38,319 Speaker 1: of there's two roads, one on either side of the 237 00:13:38,360 --> 00:13:41,040 Speaker 1: tracks parallel to it, and they'll go and they'll wait 238 00:13:41,040 --> 00:13:43,840 Speaker 1: on that red light and then the gates will come down. 239 00:13:43,840 --> 00:13:46,160 Speaker 1: They're going, Ah, you gotta be kidding me. I mean, 240 00:13:46,240 --> 00:13:48,040 Speaker 1: there's a train coming and now I have to wait 241 00:13:48,040 --> 00:13:50,040 Speaker 1: through this. Yeah, this was gonna be maybe a min 242 00:13:50,080 --> 00:13:52,440 Speaker 1: and a half way, and now I'm looking at upwards 243 00:13:52,440 --> 00:13:54,880 Speaker 1: of three to ten minutes just fitting on the train. 244 00:13:55,080 --> 00:13:57,160 Speaker 1: I gotta say, though, I did have that happen to 245 00:13:57,160 --> 00:13:59,360 Speaker 1: me not that long ago, but it ended up being 246 00:13:59,480 --> 00:14:02,400 Speaker 1: a thing as opposed to a bad thing, because it 247 00:14:02,480 --> 00:14:07,120 Speaker 1: was a circus train. It was actually really cool. That's yeah, 248 00:14:07,559 --> 00:14:13,240 Speaker 1: um Dumbo waved, Okay, Well, actually that's that. This is 249 00:14:13,280 --> 00:14:17,120 Speaker 1: where it stops being quite so simple to explain, because 250 00:14:17,440 --> 00:14:21,480 Speaker 1: those are the signals. But triggering the signals, that's that's 251 00:14:21,520 --> 00:14:24,480 Speaker 1: a little more more tricky. Let's let's talk in a 252 00:14:24,560 --> 00:14:27,360 Speaker 1: really high level way, because if you dig down, it 253 00:14:27,400 --> 00:14:29,840 Speaker 1: just gets to the point where you really need a 254 00:14:29,920 --> 00:14:35,000 Speaker 1: good I was about, say, grounding a good understanding of 255 00:14:35,280 --> 00:14:39,840 Speaker 1: electrical engineering in order to uh, to really follow and 256 00:14:39,920 --> 00:14:43,760 Speaker 1: because probably I would guess most of our audience doesn't 257 00:14:43,800 --> 00:14:46,120 Speaker 1: have that necessarily. I'm sure there's some of you who do, 258 00:14:46,880 --> 00:14:49,400 Speaker 1: but I think the general audience probably doesn't. It would 259 00:14:49,400 --> 00:14:51,920 Speaker 1: just be it would be torturous for us to try 260 00:14:51,960 --> 00:14:53,880 Speaker 1: and walk through it. Yeah, I'm not sure that I 261 00:14:53,920 --> 00:14:58,880 Speaker 1: have the the basics down enough. Sure I don't have 262 00:14:58,920 --> 00:15:01,200 Speaker 1: the basics down, but we can talk a little bit 263 00:15:01,200 --> 00:15:05,720 Speaker 1: about it from a high level. Um that virtually any 264 00:15:05,760 --> 00:15:08,960 Speaker 1: of the crossings that have electronic signals, you're gonna see 265 00:15:09,120 --> 00:15:11,520 Speaker 1: one of those boxes like you would see at a 266 00:15:11,520 --> 00:15:14,720 Speaker 1: at an intersection in an urban environment that has a 267 00:15:14,720 --> 00:15:18,280 Speaker 1: series of relays and basically a couple of batteries in it. 268 00:15:18,720 --> 00:15:22,440 Speaker 1: You might say, why does it need the batteries? Well, Um, 269 00:15:22,560 --> 00:15:27,400 Speaker 1: the tracks around the railroad crossing have a circuit in 270 00:15:27,440 --> 00:15:32,760 Speaker 1: them that helps control the railroad crossing signals. Yeah, let's 271 00:15:33,400 --> 00:15:35,520 Speaker 1: to kind of give it a basic set, all right. 272 00:15:35,600 --> 00:15:39,600 Speaker 1: Imagine that you have a stretch of railroad track, okay, 273 00:15:40,040 --> 00:15:43,440 Speaker 1: and that you are approaching You're you're walking along the 274 00:15:43,520 --> 00:15:46,200 Speaker 1: railroad track, and you're you're gradually getting to a point 275 00:15:46,200 --> 00:15:51,800 Speaker 1: where the railroad is going to intersect with a road. Now, 276 00:15:52,080 --> 00:15:54,920 Speaker 1: as you're walking along that track, you will eventually come 277 00:15:54,920 --> 00:15:58,280 Speaker 1: to a point where there will be a special insulator 278 00:15:58,480 --> 00:16:03,840 Speaker 1: block that is on each rail. Now, this insulator block, 279 00:16:03,920 --> 00:16:06,440 Speaker 1: the whole reason for this is to allow there to 280 00:16:06,520 --> 00:16:09,640 Speaker 1: be a circuit along a stretch of track. If you 281 00:16:09,680 --> 00:16:12,440 Speaker 1: didn't have that insulator block there, the the electricity would 282 00:16:12,480 --> 00:16:16,120 Speaker 1: just flow through the entire track and just disperse essentially 283 00:16:16,720 --> 00:16:20,480 Speaker 1: because you would have like the world's biggest circuit. So 284 00:16:20,520 --> 00:16:22,560 Speaker 1: you have to block it off. Yeah, and this is 285 00:16:22,600 --> 00:16:26,560 Speaker 1: not the kind of charge like you'd see on light rail, um, 286 00:16:26,600 --> 00:16:28,480 Speaker 1: you know the third rail. Yeah, this is not to 287 00:16:28,680 --> 00:16:31,240 Speaker 1: provide power to the train at all. No, No, it's 288 00:16:31,280 --> 00:16:35,640 Speaker 1: just detection system. Yeah exactly. So you've got you've got 289 00:16:35,680 --> 00:16:39,840 Speaker 1: these insulators, that's what blocks the electric signal from continuing through. Uh, 290 00:16:40,120 --> 00:16:44,280 Speaker 1: You've got and you have relays connecting the two tracks together, 291 00:16:44,520 --> 00:16:47,840 Speaker 1: and you constantly have a low level of power going 292 00:16:47,920 --> 00:16:53,800 Speaker 1: through this this basic circuit all right. Now, Uh, there's 293 00:16:53,840 --> 00:16:59,720 Speaker 1: usually another insulator block somewhere near where the actual road intersects, 294 00:17:00,040 --> 00:17:03,040 Speaker 1: and then you have a second set of circuits on 295 00:17:03,080 --> 00:17:06,199 Speaker 1: the other side and in its most basic form. And 296 00:17:06,240 --> 00:17:08,439 Speaker 1: the reason for that is so that you can detect 297 00:17:08,480 --> 00:17:11,399 Speaker 1: when the train passes from one one part of the 298 00:17:11,440 --> 00:17:14,560 Speaker 1: track to another part. And that's important because eventually you're 299 00:17:14,600 --> 00:17:18,000 Speaker 1: gonna have to have these signals stop signaling. You have 300 00:17:18,040 --> 00:17:21,280 Speaker 1: to have something that tells the electronics, Hey, the train's gone, 301 00:17:21,560 --> 00:17:23,640 Speaker 1: turn off the flashers, turn off the bell, and lift 302 00:17:23,680 --> 00:17:26,520 Speaker 1: the gates. Yes. He As a matter of fact, the 303 00:17:26,520 --> 00:17:29,399 Speaker 1: the part of the track approaching an intersection is called 304 00:17:29,480 --> 00:17:34,360 Speaker 1: the approach yes, which by the way, is not always 305 00:17:34,400 --> 00:17:38,280 Speaker 1: the same side because trains, because some tracks will allow 306 00:17:38,359 --> 00:17:42,640 Speaker 1: trains that travel in either direction, So the approach is 307 00:17:42,680 --> 00:17:46,520 Speaker 1: completely dependent upon the direction the train is coming from 308 00:17:46,560 --> 00:17:49,800 Speaker 1: at any particular time. So the approach side will change 309 00:17:49,840 --> 00:17:53,720 Speaker 1: depending on the where the trains coming from. Um. Now, 310 00:17:54,160 --> 00:17:58,800 Speaker 1: when a train crosses over the insulator and hits the 311 00:17:58,840 --> 00:18:02,480 Speaker 1: section of track where you've got that circuit, the trains 312 00:18:02,520 --> 00:18:06,679 Speaker 1: wheels are steel. The axle connecting the wheels are steel. 313 00:18:07,920 --> 00:18:11,000 Speaker 1: This massive amount of steel when it makes contact with 314 00:18:11,080 --> 00:18:15,520 Speaker 1: the tracks creates a short circuit, which means that it's 315 00:18:15,560 --> 00:18:17,600 Speaker 1: it's it's pulling the power, so it's no longer going 316 00:18:17,640 --> 00:18:19,800 Speaker 1: through the relay like it normally what it's going through 317 00:18:19,800 --> 00:18:24,879 Speaker 1: the axle instead, and that's what is That's what creates 318 00:18:24,960 --> 00:18:28,360 Speaker 1: the the alert for the signaling system that hey, there's 319 00:18:28,359 --> 00:18:32,680 Speaker 1: a train coming. Now. There are other problems with this, yes, 320 00:18:33,080 --> 00:18:34,800 Speaker 1: one of the big ones is that this does not 321 00:18:34,960 --> 00:18:39,199 Speaker 1: tell we're acting like this is all like you know, 322 00:18:39,240 --> 00:18:42,560 Speaker 1: they're all coherent and cognitive. It's not. But this does 323 00:18:42,600 --> 00:18:45,919 Speaker 1: not indicate how fast that train is moving, just that 324 00:18:46,000 --> 00:18:48,600 Speaker 1: there is a short circuit, and therefore the signal should 325 00:18:48,640 --> 00:18:51,240 Speaker 1: go off right. So you have a couple of different 326 00:18:51,520 --> 00:18:53,960 Speaker 1: things you have to take into consideration there. One is, 327 00:18:55,000 --> 00:18:57,520 Speaker 1: are all the trains that are traveling on this track 328 00:18:57,960 --> 00:19:00,680 Speaker 1: generally going to be moving at the same speed. If 329 00:19:00,680 --> 00:19:03,639 Speaker 1: they are, that makes this problem way easier to solve, 330 00:19:03,680 --> 00:19:05,960 Speaker 1: because what the problem is you need to figure out 331 00:19:06,359 --> 00:19:09,920 Speaker 1: how long from the moment that this short circuit happens, 332 00:19:10,240 --> 00:19:14,879 Speaker 1: should the signals. What's the time delay between when the 333 00:19:14,880 --> 00:19:18,760 Speaker 1: short circuit happens and when the signals activate, right, because 334 00:19:18,880 --> 00:19:21,640 Speaker 1: if the train is too far back and the signals activate, 335 00:19:21,680 --> 00:19:24,639 Speaker 1: you you take everybody off because they're like, well, look, 336 00:19:24,680 --> 00:19:27,600 Speaker 1: the gate came down and I've been waiting here for 337 00:19:27,600 --> 00:19:30,160 Speaker 1: for fifteen seconds and I still don't see a train. 338 00:19:30,240 --> 00:19:33,720 Speaker 1: I'm just gonna go, and that's going to cause a problem. Um. 339 00:19:33,760 --> 00:19:35,480 Speaker 1: In other cases, you may have a train this moving 340 00:19:35,640 --> 00:19:39,159 Speaker 1: so quickly that when it triggers the short circuit, it 341 00:19:39,200 --> 00:19:44,200 Speaker 1: actually reaches the intersection before the signals go off, so 342 00:19:44,320 --> 00:19:46,760 Speaker 1: you have to take that into account. Now, if all 343 00:19:46,800 --> 00:19:48,760 Speaker 1: the trains are moving at the same speed, you just 344 00:19:48,880 --> 00:19:54,680 Speaker 1: figure the right distance from the crossing and you install 345 00:19:54,760 --> 00:19:58,760 Speaker 1: everything that way, and then there's no problem relatively speaking, 346 00:19:58,800 --> 00:20:01,520 Speaker 1: because the trains are always going to hit the intersection 347 00:20:01,560 --> 00:20:03,359 Speaker 1: at around the same time, so you can time it 348 00:20:03,400 --> 00:20:06,320 Speaker 1: out that way. If the trains are gonna be moving 349 00:20:06,320 --> 00:20:08,680 Speaker 1: at different speeds, then you have to figure out, okay, well, 350 00:20:09,280 --> 00:20:12,840 Speaker 1: how do I indicate how fast this train is going. 351 00:20:13,080 --> 00:20:15,520 Speaker 1: You can either fudget where you kind of take an 352 00:20:15,560 --> 00:20:17,879 Speaker 1: average speed of all the trains that tend to go 353 00:20:17,960 --> 00:20:21,639 Speaker 1: across that track, or you can pick the trains that 354 00:20:21,680 --> 00:20:25,280 Speaker 1: are the most common, like the ones that are are 355 00:20:25,400 --> 00:20:27,720 Speaker 1: usually on that track or that travel through there during 356 00:20:27,760 --> 00:20:31,439 Speaker 1: high traffic areas and use that speed. Or you can 357 00:20:31,520 --> 00:20:36,320 Speaker 1: install sensors that actually do indicate you know how fast 358 00:20:36,400 --> 00:20:39,159 Speaker 1: the train is going and then send that information to 359 00:20:39,680 --> 00:20:44,120 Speaker 1: the control system to alert it when it should initiate 360 00:20:44,200 --> 00:20:49,320 Speaker 1: the warning. So those are your various options. But yeah, 361 00:20:49,400 --> 00:20:51,960 Speaker 1: that's it's all about short circuiting, which is kind of 362 00:20:51,960 --> 00:20:54,000 Speaker 1: cool because when you think about it, you know, the 363 00:20:54,320 --> 00:20:59,800 Speaker 1: connotation of the term short circuit has usually a fairly 364 00:21:00,000 --> 00:21:03,000 Speaker 1: negative feel to it, right, you know, you know, you 365 00:21:03,080 --> 00:21:06,240 Speaker 1: normally don't want things to short circuit unless you're Johnny 366 00:21:06,280 --> 00:21:11,000 Speaker 1: five nice. Yeah, I like that. I figured I had 367 00:21:11,040 --> 00:21:15,080 Speaker 1: to work that in there. Well, he was alive, he 368 00:21:15,160 --> 00:21:20,280 Speaker 1: was theoretically, Um, So the thing is you have so 369 00:21:20,320 --> 00:21:23,000 Speaker 1: that that's basically how it knows it's coming. The question 370 00:21:23,080 --> 00:21:27,879 Speaker 1: is how the crossing signal UH is notified when the 371 00:21:27,880 --> 00:21:31,520 Speaker 1: train is gone. And so basically there are are two 372 00:21:31,560 --> 00:21:36,040 Speaker 1: sets of tracks there too, since there are two approaches, 373 00:21:36,080 --> 00:21:38,639 Speaker 1: because theoretically, if a train could come from either direction, 374 00:21:38,640 --> 00:21:41,199 Speaker 1: you would want that anyway, but you also need the 375 00:21:41,240 --> 00:21:46,320 Speaker 1: other approach to to notify it too. Because um, as 376 00:21:46,400 --> 00:21:49,199 Speaker 1: the train passes from one side of the crossing to 377 00:21:49,280 --> 00:21:53,439 Speaker 1: the other, there is another uh, there's another circuit too short. 378 00:21:54,160 --> 00:21:59,320 Speaker 1: And when both sets of circuits are therefore untriggered anymore, 379 00:21:59,359 --> 00:22:01,919 Speaker 1: that means, well, the train has come and gone, and 380 00:22:01,960 --> 00:22:04,440 Speaker 1: those signals can you know, the the arms go back 381 00:22:04,520 --> 00:22:06,320 Speaker 1: up and the lights go back off, and the bell 382 00:22:06,400 --> 00:22:10,880 Speaker 1: stops clanging most of the time, but there are problems 383 00:22:10,960 --> 00:22:13,600 Speaker 1: with it it you know, those of you who live 384 00:22:13,680 --> 00:22:18,240 Speaker 1: near railroad tracks and have seen trains do this annoying behavior. 385 00:22:18,600 --> 00:22:21,040 Speaker 1: Um because of course they probably have to. There are 386 00:22:21,080 --> 00:22:23,080 Speaker 1: reasons why they have to. But for the driver it's 387 00:22:23,119 --> 00:22:25,080 Speaker 1: kind of annoying to sit there and watch a train 388 00:22:25,840 --> 00:22:30,160 Speaker 1: stop and then back up a little bit, and you're going, 389 00:22:30,200 --> 00:22:32,280 Speaker 1: how long do I have to wait? Well, that does 390 00:22:32,359 --> 00:22:35,400 Speaker 1: happen from time to time. They're there, you know, traffic 391 00:22:35,440 --> 00:22:38,520 Speaker 1: issues to be considered. And the thing is the relays 392 00:22:38,720 --> 00:22:43,040 Speaker 1: aren't exactly endowed with a lot of artificial intelligence. They 393 00:22:43,160 --> 00:22:45,840 Speaker 1: they're either on or they're off right, And there are 394 00:22:45,840 --> 00:22:48,639 Speaker 1: times when a track, a train can pass through an 395 00:22:48,680 --> 00:22:52,120 Speaker 1: intersection and then it has to back up for traffic 396 00:22:52,119 --> 00:22:54,960 Speaker 1: reasons a little bit, and that triggers the signal again, 397 00:22:55,080 --> 00:22:58,560 Speaker 1: and then when it leaves, it's you know, there, there's 398 00:22:58,680 --> 00:23:00,440 Speaker 1: it can it can trip the signal to a point 399 00:23:00,440 --> 00:23:04,159 Speaker 1: where the next train that comes from from uh, you know, 400 00:23:04,520 --> 00:23:06,479 Speaker 1: I'm not sure if it comes from that direction from 401 00:23:06,520 --> 00:23:10,080 Speaker 1: where the train left, but it may not necessarily trip 402 00:23:10,160 --> 00:23:12,399 Speaker 1: the signal because of the way it's wired. So what 403 00:23:12,440 --> 00:23:15,960 Speaker 1: you're saying is that that because the train activated the 404 00:23:16,000 --> 00:23:19,879 Speaker 1: signal the first time, then reactivated it without crossing over 405 00:23:20,080 --> 00:23:25,240 Speaker 1: into the opposite side. Uh, you've got a faulty system. 406 00:23:24,760 --> 00:23:26,640 Speaker 1: That's how I would have said it if I were 407 00:23:26,640 --> 00:23:29,440 Speaker 1: more eloquent. Well, like I had the opportunity to really 408 00:23:29,440 --> 00:23:31,280 Speaker 1: think about it and listen to what you were saying. 409 00:23:31,320 --> 00:23:33,720 Speaker 1: So that was that was It's not that I'm it's 410 00:23:33,760 --> 00:23:38,000 Speaker 1: not that I'm pithy or anything. I just had more time. Um. Yeah, 411 00:23:38,000 --> 00:23:40,159 Speaker 1: there is a problem. There are some ways around that. 412 00:23:40,240 --> 00:23:44,200 Speaker 1: One is to create a kind of a failsafe system 413 00:23:44,240 --> 00:23:47,640 Speaker 1: where you add a third set of a third circuit 414 00:23:48,280 --> 00:23:51,720 Speaker 1: two circuit system, because remember we've got we've got the 415 00:23:51,800 --> 00:23:54,159 Speaker 1: side that the trains coming from and the side that 416 00:23:54,200 --> 00:23:57,560 Speaker 1: the train is going to. Uh, and usually that that 417 00:23:57,680 --> 00:24:01,439 Speaker 1: ends up having a break right at where the cross 418 00:24:01,560 --> 00:24:06,120 Speaker 1: is um and when usually normal in normal operation, as 419 00:24:06,200 --> 00:24:10,240 Speaker 1: one side gets activated and the other side becomes unactivated. Uh. 420 00:24:10,280 --> 00:24:12,640 Speaker 1: You that that's when it says, okay, well the train 421 00:24:12,680 --> 00:24:15,600 Speaker 1: has passed from this one side, we can now raise 422 00:24:15,680 --> 00:24:17,000 Speaker 1: the gates and turn off the lights and all this 423 00:24:17,040 --> 00:24:20,600 Speaker 1: kind of stuff. If you add a third section that's 424 00:24:20,640 --> 00:24:23,920 Speaker 1: directly over where the road crosses over, uh, and then 425 00:24:23,960 --> 00:24:27,040 Speaker 1: you you create that that can give you that extra 426 00:24:27,119 --> 00:24:29,840 Speaker 1: set of circuits there that will allow you to either 427 00:24:30,320 --> 00:24:32,440 Speaker 1: switch something off if the train does have to stop 428 00:24:32,520 --> 00:24:36,119 Speaker 1: and back up, or more importantly, I think there is 429 00:24:36,160 --> 00:24:39,680 Speaker 1: the chance that let's say the train has passed over 430 00:24:40,440 --> 00:24:45,359 Speaker 1: the the first the approach. Okay, so the end of 431 00:24:45,359 --> 00:24:47,680 Speaker 1: the train has left the approach, there's no longer any 432 00:24:47,720 --> 00:24:51,119 Speaker 1: contact there where it will create a short circuit. But 433 00:24:51,240 --> 00:24:55,960 Speaker 1: the train has not left the other side yet, It 434 00:24:56,000 --> 00:24:57,760 Speaker 1: hasn't gone through, and then it starts to back up. 435 00:24:58,040 --> 00:25:00,240 Speaker 1: You may have gotten to the point where the warning 436 00:25:00,240 --> 00:25:02,840 Speaker 1: systems have shut off and the gates have gone up, 437 00:25:02,960 --> 00:25:06,240 Speaker 1: but the train is still approaching that intersection. Right. That's 438 00:25:06,280 --> 00:25:09,000 Speaker 1: also dangerous because everyone thinks, oh, I can go through 439 00:25:09,040 --> 00:25:10,880 Speaker 1: now because the gates went up, the lights are off, 440 00:25:10,920 --> 00:25:13,439 Speaker 1: the bell is no longer ringing, but it's because that 441 00:25:13,520 --> 00:25:16,320 Speaker 1: the the full circuit hasn't been tripped yet, so the 442 00:25:16,320 --> 00:25:21,159 Speaker 1: train starts backing up and you are possibly endangered. Adding 443 00:25:21,200 --> 00:25:23,760 Speaker 1: this third circuit, where you have a section of track 444 00:25:23,840 --> 00:25:26,520 Speaker 1: in the center between the approach and the departure area, 445 00:25:27,240 --> 00:25:31,879 Speaker 1: allows you to create a fail safe. So some crossings 446 00:25:31,920 --> 00:25:33,760 Speaker 1: do have this, some don't. It all depends on when 447 00:25:33,760 --> 00:25:35,960 Speaker 1: it was built and the last time that it was 448 00:25:37,680 --> 00:25:42,240 Speaker 1: fixed really adjusted. It's called an island, yes, the section 449 00:25:42,440 --> 00:25:46,840 Speaker 1: that is directly over the road, and apparently it does 450 00:25:46,960 --> 00:25:50,359 Speaker 1: have there. There are some certain reasons why you want 451 00:25:50,400 --> 00:25:53,000 Speaker 1: it to be an island that goes over both sides, 452 00:25:53,040 --> 00:25:56,400 Speaker 1: because if you have the insulators or anything like that 453 00:25:56,840 --> 00:25:59,560 Speaker 1: built into the road itself, the thickness that the road 454 00:25:59,560 --> 00:26:02,760 Speaker 1: can actually affect the way the signal is tripped, so 455 00:26:02,800 --> 00:26:05,159 Speaker 1: you really have to uh really have to leave the 456 00:26:05,280 --> 00:26:07,199 Speaker 1: rails that crossed the road. I thought that was kind 457 00:26:07,200 --> 00:26:09,760 Speaker 1: of interesting actually, because I was I was thinking as 458 00:26:09,760 --> 00:26:12,840 Speaker 1: I started reading um reading up on it, I thought, 459 00:26:12,880 --> 00:26:14,439 Speaker 1: you know, when I go home, I'm gonna look and 460 00:26:14,480 --> 00:26:18,199 Speaker 1: see where the the insulators are that that split the 461 00:26:18,240 --> 00:26:21,080 Speaker 1: two approaches. And then as I started reading about it, 462 00:26:21,119 --> 00:26:22,639 Speaker 1: you know, it dawned to me. Yes, I mean, if 463 00:26:22,680 --> 00:26:24,600 Speaker 1: they have to repave the road or something like that, 464 00:26:24,600 --> 00:26:27,359 Speaker 1: it's going to affect that. And if the train rolls 465 00:26:27,440 --> 00:26:32,240 Speaker 1: over um that and can't actually you know, it could 466 00:26:32,240 --> 00:26:35,480 Speaker 1: actually be a problem. Um. But that that is one 467 00:26:35,480 --> 00:26:37,240 Speaker 1: way of doing it. And then there there are other 468 00:26:37,359 --> 00:26:41,240 Speaker 1: pieces of equipment that can be added to refine the 469 00:26:41,800 --> 00:26:46,399 Speaker 1: capabilities of the signaling equipment. For one thing, there at 470 00:26:46,440 --> 00:26:49,680 Speaker 1: a really you know, nice new modern crossing, you might 471 00:26:49,760 --> 00:26:52,800 Speaker 1: have a lot of solid state electronics and you avoid 472 00:26:52,840 --> 00:26:55,879 Speaker 1: all these these circuit relays and stuff and you just 473 00:26:56,119 --> 00:27:00,159 Speaker 1: you use solid state instead, which it works kind of 474 00:27:00,280 --> 00:27:03,440 Speaker 1: on the same principle, except that there are a lot 475 00:27:03,520 --> 00:27:07,640 Speaker 1: fewer parts. You know, it sends a lot of electronic 476 00:27:07,720 --> 00:27:11,920 Speaker 1: signals directly to the the traffic control system for that 477 00:27:12,040 --> 00:27:15,840 Speaker 1: particular crossing. But but I mean, you know that's it's 478 00:27:15,880 --> 00:27:19,920 Speaker 1: not by any means a universal thing. It's it's all regional. 479 00:27:20,000 --> 00:27:23,080 Speaker 1: And you know, some areas are going to get that 480 00:27:23,119 --> 00:27:28,360 Speaker 1: equipment much faster than others, and some may never get it. Frankly. Yeah, yeah, now, Now, 481 00:27:28,400 --> 00:27:32,159 Speaker 1: Mattiness also said that there are some signals that use 482 00:27:32,200 --> 00:27:38,280 Speaker 1: transceivers built into the boxes that that help identify how 483 00:27:38,359 --> 00:27:42,240 Speaker 1: quickly the train is moving. Um. Basically by measuring the 484 00:27:42,320 --> 00:27:47,000 Speaker 1: voltage um, you know, and judging by the impedance of 485 00:27:47,040 --> 00:27:49,720 Speaker 1: the wheels on the train moving, it can kind of 486 00:27:50,240 --> 00:27:54,359 Speaker 1: tell as the voltage drops how quickly the train is 487 00:27:54,400 --> 00:27:57,880 Speaker 1: going to approach the intersection, and can drop the signals 488 00:27:57,880 --> 00:28:00,960 Speaker 1: at a more appropriate time. UM. But you definitely want 489 00:28:00,960 --> 00:28:08,879 Speaker 1: to make yeah, yeah, English major fair enough. Um. But 490 00:28:09,000 --> 00:28:12,240 Speaker 1: there are also some of the newer intersections also use 491 00:28:12,480 --> 00:28:16,040 Speaker 1: motion detectors, which which can help identify these things. But 492 00:28:16,640 --> 00:28:19,520 Speaker 1: in essence, that's that's what it's doing. It's just basically 493 00:28:19,720 --> 00:28:23,960 Speaker 1: looking for information from the rails themselvesselves in a lot 494 00:28:23,960 --> 00:28:27,600 Speaker 1: of cases. UM. And I think it's it's probably uh 495 00:28:27,800 --> 00:28:32,639 Speaker 1: trickier because in urban environments simply because you have uh, 496 00:28:32,800 --> 00:28:35,359 Speaker 1: you know, more intersections to worry about, and you also 497 00:28:35,400 --> 00:28:39,880 Speaker 1: have more car traffic. And like in the case of 498 00:28:39,880 --> 00:28:43,120 Speaker 1: of the intersection near my house, you've got two roads parallel, 499 00:28:43,160 --> 00:28:45,600 Speaker 1: so you've got two traffic lights to deal with at 500 00:28:45,640 --> 00:28:48,960 Speaker 1: that railroad crossing because the piece of road crosses too 501 00:28:49,720 --> 00:28:56,320 Speaker 1: uh car intersections you know, within my guests probably uh 502 00:28:56,520 --> 00:28:58,840 Speaker 1: hundred feet of one another. So it's a very short 503 00:28:58,920 --> 00:29:01,880 Speaker 1: section of where there are two intersections right on the 504 00:29:01,880 --> 00:29:04,520 Speaker 1: other side of the railroad College avenues that way. So yeah, 505 00:29:04,560 --> 00:29:08,040 Speaker 1: that's uh College Avenue in Decab Avenue. Yeah, yeah, that's 506 00:29:08,040 --> 00:29:11,040 Speaker 1: true that those are from my Atlanta peeps. Yea. So 507 00:29:11,240 --> 00:29:13,640 Speaker 1: it's just one of those situations where you just got 508 00:29:13,680 --> 00:29:16,760 Speaker 1: a lot to be concerned with. And I imagine that 509 00:29:17,640 --> 00:29:22,320 Speaker 1: as time wears on, these uh, these roadways and railways 510 00:29:22,320 --> 00:29:25,120 Speaker 1: will be updated with more solid state technology that will 511 00:29:25,120 --> 00:29:28,920 Speaker 1: give you a better idea of what's going on and when. Um. 512 00:29:29,480 --> 00:29:32,800 Speaker 1: But you know that the the systems that they've had 513 00:29:32,840 --> 00:29:36,560 Speaker 1: have been somewhat uh, somewhat elegant, I think in their design. 514 00:29:36,640 --> 00:29:39,240 Speaker 1: I mean they're just they're simple, and I think sometimes 515 00:29:39,240 --> 00:29:43,880 Speaker 1: that can be for the best. Yeah, uh, keeping keeping 516 00:29:43,880 --> 00:29:47,400 Speaker 1: it simple stupid is always a good uh philosophy to follow. 517 00:29:47,880 --> 00:29:51,959 Speaker 1: And and we should add that the railroad signals. Of 518 00:29:51,960 --> 00:29:54,520 Speaker 1: course we're just talking about the crossing ones. There are 519 00:29:54,560 --> 00:29:58,640 Speaker 1: there are lots more signals that that railroad companies use 520 00:29:59,000 --> 00:30:03,440 Speaker 1: to manage traffic on the rails. And it seems like 521 00:30:03,480 --> 00:30:06,480 Speaker 1: it might you know, for at first blush, you do think, well, 522 00:30:06,520 --> 00:30:08,440 Speaker 1: how how tricky could it be, but then you think, 523 00:30:08,440 --> 00:30:11,960 Speaker 1: wait a minute, this is a dedicated pathway that only 524 00:30:12,120 --> 00:30:15,920 Speaker 1: one vehicle can travel in a direction at in a 525 00:30:16,000 --> 00:30:19,120 Speaker 1: particular area at a time. So it does get really 526 00:30:19,120 --> 00:30:21,320 Speaker 1: complicated when you think, oh, well, how many trains are 527 00:30:21,360 --> 00:30:23,720 Speaker 1: on the system. How many systems are we talking about? 528 00:30:24,200 --> 00:30:27,760 Speaker 1: Because the rules from system to system change a little bit, 529 00:30:28,560 --> 00:30:30,720 Speaker 1: you know, like the rules in the Northeast are slightly 530 00:30:30,720 --> 00:30:34,240 Speaker 1: different than the rules in the southeast. Yeah. Actually, when 531 00:30:34,240 --> 00:30:37,160 Speaker 1: we were starting to talk about what podcasts we wanted 532 00:30:37,200 --> 00:30:40,800 Speaker 1: to record, um, I suggested this to Jonathan, and I said, well, 533 00:30:40,920 --> 00:30:43,720 Speaker 1: let's talk about all the different kinds of signals. And 534 00:30:43,760 --> 00:30:47,040 Speaker 1: then when we got into, uh, the complexities of how 535 00:30:47,240 --> 00:30:50,480 Speaker 1: the systems are triggered for railroad crossings, we realized we 536 00:30:50,520 --> 00:30:52,800 Speaker 1: wouldn't be able to get that in as much detail 537 00:30:52,880 --> 00:30:56,000 Speaker 1: as possible. But if you're interested in knowing more about that, 538 00:30:56,160 --> 00:30:58,680 Speaker 1: please let us know, and you know, maybe we can 539 00:30:58,720 --> 00:31:02,160 Speaker 1: revisit that. But I've always been interested in the switching 540 00:31:02,280 --> 00:31:05,520 Speaker 1: systems and how uh you know they they operate that 541 00:31:05,640 --> 00:31:08,000 Speaker 1: because um, you know, I'm I'm kind of interested in 542 00:31:08,080 --> 00:31:10,600 Speaker 1: trains anyway, but you know, the signals that say, okay, 543 00:31:10,600 --> 00:31:12,640 Speaker 1: wait you can't come this way just yet. And how 544 00:31:12,640 --> 00:31:16,480 Speaker 1: they shunt tracks from one, uh you know, from a 545 00:31:16,600 --> 00:31:19,160 Speaker 1: train from one set of tracts to another set of 546 00:31:19,280 --> 00:31:22,200 Speaker 1: tracks using those electrical systems. So if you if you're 547 00:31:22,240 --> 00:31:24,280 Speaker 1: interested in doing that, please let us know and we'll 548 00:31:24,360 --> 00:31:27,000 Speaker 1: come back to trains in the future. Clearly, Chris needs 549 00:31:27,040 --> 00:31:30,120 Speaker 1: to go see the film Unstoppable. That's the one with 550 00:31:30,240 --> 00:31:33,640 Speaker 1: Denzel Washington and the train. That's the missile, the size 551 00:31:33,680 --> 00:31:39,840 Speaker 1: of the Chrysler building. Stop it, it'll be awesome. Oh 552 00:31:40,160 --> 00:31:44,760 Speaker 1: that's no train, that's a space station. See how many 553 00:31:45,320 --> 00:31:47,480 Speaker 1: random quotes we can throw it? Yeah, I think you 554 00:31:47,600 --> 00:31:51,520 Speaker 1: just mixed up those a little maybe to tad, I'm 555 00:31:51,520 --> 00:31:56,360 Speaker 1: a little loopy today. Al right, guys, well they loopier 556 00:31:56,360 --> 00:32:01,040 Speaker 1: than normal. That wraps up this discussion on text UF. 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