WEBVTT 00:00:00.000 --> 00:00:02.500 It's an Apple podcast title, Cracking the RKM 00:00:02.500 --> 00:00:04.980 Code, The Hidden Language of Electronic Schematics, 00:00:05.280 --> 00:00:08.759 Apple podcast description. Ever wonder how engineers 00:00:08.759 --> 00:00:10.679 read the cryptic letters and numbers on tiny 00:00:10.679 --> 00:00:13.419 circuit boards? In this deep dive, we decode 00:00:13.419 --> 00:00:16.460 the RKM code, the ingenious notation system defined 00:00:16.460 --> 00:00:21.800 by the IEC 60062 standard. Discover how replacing 00:00:21.800 --> 00:00:24.160 a simple decimal point with letters like K and 00:00:24.160 --> 00:00:27.539 R revolutionized resistor values, capacitor notation, 00:00:27.820 --> 00:00:30.690 and circuit diagrams worldwide. From solving 00:00:30.690 --> 00:00:32.810 vintage photocopying disasters to optimizing 00:00:32.810 --> 00:00:35.590 modern bills of materials, learn the hidden logic 00:00:35.590 --> 00:00:38.270 behind electronic components. Perfect for curious 00:00:38.270 --> 00:00:40.189 learners, tech enthusiasts, and anyone looking 00:00:40.189 --> 00:00:42.170 to understand the secret language powering our 00:00:42.170 --> 00:00:45.049 electronic devices. Keywords, RKM code, resistor 00:00:45.049 --> 00:00:49.310 values, capacitor notation, IEC 60062, electronic 00:00:49.310 --> 00:00:51.490 schematics, circuit diagrams, bill of materials. 00:00:51.950 --> 00:00:54.390 Have you ever maybe cracked open a broken remote 00:00:54.390 --> 00:00:56.350 control to try and fix it? Or maybe you've peeked 00:00:56.350 --> 00:00:58.070 inside a desktop computer and just wondered what 00:00:58.070 --> 00:00:59.909 all those tiny printed labels actually mean. 00:01:00.030 --> 00:01:02.109 You mean those little alphanumeric strings like 00:01:02.109 --> 00:01:05.329 4K7 or 3V3? Yeah, exactly. They're printed on 00:01:05.329 --> 00:01:07.609 practically every little surface mount component 00:01:07.609 --> 00:01:10.950 in there. And today we are taking a deep dive 00:01:10.950 --> 00:01:13.549 into the architecture of that specific notation. 00:01:13.969 --> 00:01:16.349 You are going to learn how to read the hidden 00:01:16.349 --> 00:01:18.829 language of electronics. It really is a language 00:01:18.829 --> 00:01:20.790 that hides in plain sight, isn't it? It totally 00:01:20.790 --> 00:01:23.650 is. And our mission today is to demystify this. 00:01:23.730 --> 00:01:25.709 We're going to break down the RKM code, which 00:01:25.709 --> 00:01:28.109 comes from a Wikipedia article detailing the 00:01:28.109 --> 00:01:32.790 IEC 60062 standard. We want to explore the surprising 00:01:32.790 --> 00:01:35.670 and honestly fascinating logistical problems 00:01:35.670 --> 00:01:38.629 that this code was invented to solve. Because 00:01:38.629 --> 00:01:41.370 it's not just about some dry, boring engineering 00:01:41.370 --> 00:01:44.489 standard. This is a masterclass in solving massive 00:01:44.489 --> 00:01:47.109 industrial problems with very simple design tweaks. 00:01:47.819 --> 00:01:50.900 The system was formalized way back in 1952, and 00:01:50.900 --> 00:01:53.420 it represents this absolute triumph of functionality. 00:01:53.739 --> 00:01:55.379 Okay, let's unpack this. The immediate question 00:01:55.379 --> 00:01:57.000 that comes up when you're looking at a component 00:01:57.000 --> 00:02:00.299 labeled 4K7 is, why couldn't engineers just write 00:02:00.299 --> 00:02:03.340 4 .7 ohms right on the part? I mean, standard 00:02:03.340 --> 00:02:06.400 math uses decimal points. Why abandon the dot? 00:02:06.750 --> 00:02:08.870 It seems completely counterintuitive at first. 00:02:08.990 --> 00:02:10.710 The decimal point is foundational, right? Right. 00:02:10.750 --> 00:02:12.930 Yeah, exactly. But you have to factor in the 00:02:12.930 --> 00:02:15.849 physical reality of manufacturing and document 00:02:15.849 --> 00:02:19.590 reproduction back in the 1950s. The massive flaw 00:02:19.590 --> 00:02:22.310 with the decimal point really comes down to scale. 00:02:22.509 --> 00:02:24.650 Because the components are so incredibly tiny. 00:02:24.849 --> 00:02:26.810 Right. Resistors and capacitors are inherently 00:02:26.810 --> 00:02:30.610 small. Printing a legible, isolated dot on a 00:02:30.610 --> 00:02:32.870 surface that is barely a few millimeters across 00:02:32.870 --> 00:02:35.409 that is a very difficult manufacturing tolerance 00:02:35.409 --> 00:02:37.770 to maintain. And even if you print it perfectly, 00:02:38.030 --> 00:02:40.110 these things are out in the real world. Exactly. 00:02:40.310 --> 00:02:43.509 A tiny scratch on the casing or a speck of dust 00:02:43.509 --> 00:02:46.389 or even a microscopic drop of solder can easily 00:02:46.389 --> 00:02:49.590 obscure that decimal point. Or worse, mimic one 00:02:49.590 --> 00:02:52.810 where it shouldn't be. Oh, wow. So a tiny speck 00:02:52.810 --> 00:02:54.650 of dirt isn't just cosmetic. It fundamentally 00:02:54.650 --> 00:02:57.030 changes the data the engineer is reading. It 00:02:57.030 --> 00:02:59.250 does. And the problem actually gets much worse 00:02:59.250 --> 00:03:01.310 when you step back from the physical part and 00:03:01.310 --> 00:03:03.889 look at the circuit diagrams, the blueprints. 00:03:03.969 --> 00:03:06.349 Oh, right. Because in the 50s, they weren't sending 00:03:06.349 --> 00:03:09.400 PDFs around. It's not at all. Engineers relied 00:03:09.400 --> 00:03:11.960 on diazeprints and early photocopying techniques 00:03:11.960 --> 00:03:15.099 to distribute schematics to factories. And the 00:03:15.099 --> 00:03:17.639 quality of those machines was notoriously bad. 00:03:18.280 --> 00:03:20.659 Contrast degraded so fast with every copy. If 00:03:20.659 --> 00:03:23.099 it was a single dot of ink, like a decimal point 00:03:23.099 --> 00:03:25.099 could just disappear. It would vanish entirely. 00:03:25.680 --> 00:03:28.430 Or... A speck of dirt on the copier glass would 00:03:28.430 --> 00:03:31.610 add a decimal point. Yeah. It was a massive recognized 00:03:31.610 --> 00:03:34.050 problem in drafting rooms. The stakes there are 00:03:34.050 --> 00:03:36.449 incredibly high because if you're building a 00:03:36.449 --> 00:03:39.569 power supply from a bad copy, a missing dot turns 00:03:39.569 --> 00:03:43.370 a 4 .7 ohm resistor into a 47 ohm resistor. And 00:03:43.370 --> 00:03:46.189 that is a severe error. You drop a 47 ohm resistor 00:03:46.189 --> 00:03:49.069 into a circuit expecting 4 .7 and you fundamentally 00:03:49.069 --> 00:03:51.650 alter the current flow. Best case, it just doesn't 00:03:51.650 --> 00:03:54.680 turn on. Right. But worst case, in those old 00:03:54.680 --> 00:03:57.500 high voltage analog circuits, components overheat, 00:03:57.500 --> 00:03:59.360 you get thermal runaway, and the device could 00:03:59.360 --> 00:04:01.840 literally catch fire. From a missing dot of ink. 00:04:01.979 --> 00:04:03.800 Literally a fire hazard from a missing pixel. 00:04:03.879 --> 00:04:06.319 That is wild. So the engineers realized the decimal 00:04:06.319 --> 00:04:08.300 point was this unacceptable point of failure. 00:04:08.500 --> 00:04:11.159 And that brings us to the RKM innovation, because 00:04:11.159 --> 00:04:13.840 the solution is brilliantly efficient. It really 00:04:13.840 --> 00:04:16.560 is. The code completely eliminates the decimal 00:04:16.560 --> 00:04:19.620 separator. Instead of hoping a dot survives the 00:04:19.620 --> 00:04:22.550 copier, they replaced it with a letter. And that 00:04:22.550 --> 00:04:24.310 letter does two things at once. It tells you 00:04:24.310 --> 00:04:25.910 where the decimal goes, and it tells you the 00:04:25.910 --> 00:04:27.889 multiplier. It is the ultimate data compression. 00:04:28.209 --> 00:04:30.089 Let's give some specific examples to make this 00:04:30.089 --> 00:04:32.389 concrete for you listening. If a circuit needs 00:04:32.389 --> 00:04:36.329 a fractional value, say 0 .47 ohms, you don't 00:04:36.329 --> 00:04:40.149 write 0 .47. You write R47. The R takes the place 00:04:40.149 --> 00:04:42.160 of the decimal. And if you bump that up to 4 00:04:42.160 --> 00:04:44.519 .7 ohms, the letter just shifts right. It becomes 00:04:44.519 --> 00:04:47.560 4R7. And it scales up perfectly. Instead of writing 00:04:47.560 --> 00:04:51.339 out 47 ,000 ohms or 47 kilohms, you drop the 00:04:51.339 --> 00:04:53.920 decimal entirely and just write 47K. It's so 00:04:53.920 --> 00:04:56.899 clean. You can photocopy that schematic 20 times, 00:04:57.019 --> 00:05:00.319 cover it in coffee stains, and a K or an R is 00:05:00.319 --> 00:05:02.120 still going to be readable. It survives the degradation. 00:05:02.670 --> 00:05:05.750 It's just so simple and elegant. But moving past 00:05:05.750 --> 00:05:08.250 the mechanics of the decimal replacement, I am 00:05:08.250 --> 00:05:10.149 really curious about how they pick the actual 00:05:10.149 --> 00:05:12.250 letters. Let's look at the alphabet of electronics 00:05:12.250 --> 00:05:15.410 here. Starting with resistors, the rules use 00:05:15.410 --> 00:05:17.970 uppercase letters, right? They do. And they're 00:05:17.970 --> 00:05:20.750 mostly based on the standard SI prefixes that 00:05:20.750 --> 00:05:23.250 engineers already knew. Right. So K for kilo, 00:05:23.470 --> 00:05:27.410 M for mega, G for giga, and T for tera. Exactly. 00:05:27.850 --> 00:05:30.029 But there's a big exception at the low end of 00:05:30.029 --> 00:05:32.720 the scale. The standard prefix for milli -one 00:05:32.720 --> 00:05:35.800 -thousandth is a lowercase m, but the standard 00:05:35.800 --> 00:05:38.720 requires uppercase letters for resistors. Oh, 00:05:38.759 --> 00:05:40.680 I see where this is going. Yeah, if you used 00:05:40.680 --> 00:05:43.040 an uppercase m for milli, it would completely 00:05:43.040 --> 00:05:45.259 collide with the uppercase m for mega. That's 00:05:45.259 --> 00:05:47.779 an order of magnitude error of a billion. A billion. 00:05:47.819 --> 00:05:50.180 It would be catastrophic. So to fix that, the 00:05:50.180 --> 00:05:52.220 standard introduced the letter L to represent 00:05:52.220 --> 00:05:54.360 milli in resistor values. Okay, that makes sense. 00:05:54.480 --> 00:05:56.660 It preserves the uppercase rule but avoids the 00:05:56.660 --> 00:05:59.709 mega collision. But here is my favorite trivia 00:05:59.709 --> 00:06:03.050 point from the deep dive. The R mystery. We just 00:06:03.050 --> 00:06:07.310 said 4R7 means 4 .7 ohms. But the official Greek 00:06:07.310 --> 00:06:10.629 symbol for ohms is omega. So why not write 4 00:06:10.629 --> 00:06:13.129 omega 7? This is one of those great moments where 00:06:13.129 --> 00:06:16.009 typography dictates technology. You have to imagine 00:06:16.009 --> 00:06:18.310 the environment back then. They were using mechanical 00:06:18.310 --> 00:06:21.050 typewriters, early teleprinters, rudimentary 00:06:21.050 --> 00:06:23.949 CAD environments. Those early character encodings. 00:06:24.329 --> 00:06:26.790 simply didn't have the Greek omega symbol. They 00:06:26.790 --> 00:06:28.490 didn't have the physical keys for it. They just 00:06:28.490 --> 00:06:31.149 couldn't type it. Exactly. So they needed a substitute 00:06:31.149 --> 00:06:35.110 from the standard Latin alphabet. And R was the 00:06:35.110 --> 00:06:38.370 perfect choice. Visually, an uppercase R kind 00:06:38.370 --> 00:06:40.889 of looks like an omega if you squint, which have 00:06:40.889 --> 00:06:42.930 the drafting teams adjust. Plus it stands for 00:06:42.930 --> 00:06:45.050 resistance in multiple languages, so it's a great 00:06:45.050 --> 00:06:48.050 mnemonic. Yes. But the most important reason 00:06:48.050 --> 00:06:50.790 they chose R is that it allowed them to actively 00:06:50.790 --> 00:06:53.759 avoid using the letter E. Which is a huge deal 00:06:53.759 --> 00:06:56.800 because E means scientific exponentiation in 00:06:56.800 --> 00:07:00.120 engineering math. Exactly. E notation. If a schematic 00:07:00.120 --> 00:07:04.459 used E for ohms and an engineer saw 4E7, they 00:07:04.459 --> 00:07:06.879 might read that as 4 times 10 to the 7th power. 00:07:07.060 --> 00:07:09.639 40 million. Right. And if you put a 40 megohm 00:07:09.639 --> 00:07:12.459 part into a 4 .7 ohm slot, the circuit is dead. 00:07:12.819 --> 00:07:15.990 So choosing R. prevented that specific cognitive 00:07:15.990 --> 00:07:18.250 error. That is so smart. Okay, let's look at 00:07:18.250 --> 00:07:20.209 capacitors because they follow a similar rule 00:07:20.209 --> 00:07:23.389 but with a twist to avoid board confusion. Capacitors 00:07:23.389 --> 00:07:26.529 use lowercase letters. They do. That gives the 00:07:26.529 --> 00:07:29.550 engineer an immediate visual cue about what kind 00:07:29.550 --> 00:07:31.870 of component they are looking at. For capacitors, 00:07:31.949 --> 00:07:35.310 it's P for pico, M for nano, and M for milli. 00:07:35.509 --> 00:07:38.350 And notice that lowercase m is perfectly safe 00:07:38.350 --> 00:07:41.290 here. Yes, because capacitors rarely reach the 00:07:41.290 --> 00:07:44.189 megafarad range on a normal board, and the lowercase 00:07:44.189 --> 00:07:46.649 rule keeps it distinct from the resistor's uppercase 00:07:46.649 --> 00:07:49.089 M. But there is another typewriter workaround 00:07:49.089 --> 00:07:51.430 here, right? With the microfarad. Right. The 00:07:51.430 --> 00:07:53.689 official SI symbol for micro is the Greek letter 00:07:53.689 --> 00:07:57.490 mu. Which, again, was not on a 1950s typewriter. 00:07:57.709 --> 00:08:00.230 Not at all. So the standard has this pragmatic 00:08:00.230 --> 00:08:02.970 workaround. When the Greek alphabet isn't there, 00:08:03.149 --> 00:08:05.850 you substitute mu with a standard lowercase u. 00:08:06.410 --> 00:08:09.060 Or... an uppercase U if the system only has capitals. 00:08:09.120 --> 00:08:11.360 Well, the base unit for Farad gets reserved as 00:08:11.360 --> 00:08:14.560 a capital F. Exactly. So a 4 .7 microfarad capacitor 00:08:14.560 --> 00:08:17.699 gets documented cleanly as 4U7. Here's where 00:08:17.699 --> 00:08:19.579 it gets really interesting, though. We've talked 00:08:19.579 --> 00:08:21.399 about making things readable and stopping local 00:08:21.399 --> 00:08:24.720 errors, but this code actually saves companies 00:08:24.720 --> 00:08:26.879 massive amounts of money. It goes way beyond 00:08:26.879 --> 00:08:29.040 just being easy to read. It changes everything 00:08:29.040 --> 00:08:31.779 about the bill of materials, the B of EM. For 00:08:31.779 --> 00:08:34.519 those not in manufacturing. The BELO is basically 00:08:34.519 --> 00:08:36.919 the master recipe. It's the spreadsheet listing 00:08:36.919 --> 00:08:39.240 every single raw material and component needed 00:08:39.240 --> 00:08:41.340 to build a device. And for something like a modern 00:08:41.340 --> 00:08:43.960 motherboard, that spreadsheet has thousands of 00:08:43.960 --> 00:08:46.379 individual resistors on it. Right. And if you 00:08:46.379 --> 00:08:48.779 have ever tried to sort a big database or an 00:08:48.779 --> 00:08:50.879 Excel sheet, you know computers are very literal. 00:08:51.019 --> 00:08:53.399 If you take a traditional list of values, let's 00:08:53.399 --> 00:08:57.679 say 1 .0 ohms, 3 .3 ohms, 3 .3 coulombs, 3 .6 00:08:57.679 --> 00:09:01.379 coulombs, 4 .7 coulombs, 4 .7 megohms, and 5 00:09:01.379 --> 00:09:04.059 .1 coulombs. Standard alphanumeric sort will 00:09:04.059 --> 00:09:06.039 just make a mess of that list. It's pure chaos. 00:09:06.240 --> 00:09:08.500 The computer just reads left to right. It lumps 00:09:08.500 --> 00:09:10.519 everything starting with a three foot together. 00:09:10.779 --> 00:09:13.799 So your list violently jumps from ohms to kilohms 00:09:13.799 --> 00:09:16.519 to megaohms. Your 3 .3 ohm part is sitting right 00:09:16.519 --> 00:09:19.039 next to your 3 .3 kilohm part. One is a thousand 00:09:19.039 --> 00:09:21.059 times stronger, but the computer thinks they 00:09:21.059 --> 00:09:23.220 belong together. Which is a nightmare for a procurement 00:09:23.220 --> 00:09:25.779 team trying to consolidate orders. But the RKM 00:09:25.779 --> 00:09:28.279 code natively solves this sorting problem. Yes, 00:09:28.320 --> 00:09:31.389 without any fancy programming. If we translate 00:09:31.389 --> 00:09:35.070 that exact same list into the RKM code, the magic 00:09:35.070 --> 00:09:39.909 becomes obvious. The line is now 1R0 3K3 3K6 00:09:39.909 --> 00:09:44.230 3R3 4K7 4M7 5K1. And when you hit sort A to Z 00:09:44.230 --> 00:09:46.870 on that list... The multiplier letter is securely 00:09:46.870 --> 00:09:49.309 in the middle, so it forces the values to cluster 00:09:49.309 --> 00:09:52.169 perfectly by magnitude. Because K comes before 00:09:52.169 --> 00:09:55.149 M in the alphabet, all your kiloms clump together 00:09:55.149 --> 00:09:59.870 natively. Exactly. 3K3, 3K6, 4K7, 5K1. They fall 00:09:59.870 --> 00:10:03.049 into a perfect ascending sequence. And the megaohms, 00:10:03.090 --> 00:10:05.549 like 4M7, get pushed further down into their 00:10:05.549 --> 00:10:07.629 own group. If we connect this to the bigger picture, 00:10:07.769 --> 00:10:10.210 this is a superpower for procurement. Oh, absolutely. 00:10:10.570 --> 00:10:12.330 When a procurement specialist looks at... an 00:10:12.330 --> 00:10:15.289 RKM sorted B ohm, they spot redundancies instantly. 00:10:15.590 --> 00:10:18.370 If they see a 4K7 resistor right next to a 5K1 00:10:18.370 --> 00:10:19.929 resistor, they can go to the design engineers 00:10:19.929 --> 00:10:21.970 and ask, hey, can we just use one value here? 00:10:22.110 --> 00:10:24.029 Can we standardize this? Right. And if the engineers 00:10:24.029 --> 00:10:26.889 say yes, the factory just erased an entire line 00:10:26.889 --> 00:10:28.690 item from the supply chain. They can buy the 00:10:28.690 --> 00:10:31.529 4K7 parts in bulk, get a volume discount, and 00:10:31.529 --> 00:10:33.870 the factory floor has one less reel of parts 00:10:33.870 --> 00:10:36.580 to load into the machines. Inventory costs go 00:10:36.580 --> 00:10:39.659 down, assembly speed goes up, all because they 00:10:39.659 --> 00:10:42.500 shifted the letter K to the middle of the string. 00:10:42.799 --> 00:10:45.519 It's mind -blowing that such a small typographical 00:10:45.519 --> 00:10:48.580 change optimizes global logistics. And honestly, 00:10:48.740 --> 00:10:51.200 it's so elegant that the code leaked outside 00:10:51.200 --> 00:10:54.200 its official boundaries. It did. engineers started 00:10:54.200 --> 00:10:56.600 applying it to entirely different things, like 00:10:56.600 --> 00:10:59.059 voltages. Right, because modern software has 00:10:59.059 --> 00:11:01.279 the exact same constraints as old glue prints. 00:11:01.559 --> 00:11:03.940 You can't use decimal points in computer file 00:11:03.940 --> 00:11:06.299 names or variable names. The operating system 00:11:06.299 --> 00:11:08.539 will think the dot is a file extension. Exactly. 00:11:08.720 --> 00:11:11.500 So if an engineer needs a 3 .3 volt power rail, 00:11:11.659 --> 00:11:14.639 they don't name the file 3 .3 volts. They co 00:11:14.639 --> 00:11:18.570 -opt the RKM code and write 3V3. The V just seamlessly 00:11:18.570 --> 00:11:20.809 replaces the dot. You see it with power supplies 00:11:20.809 --> 00:11:23.970 too, right? Using the letter P, like a 1 .8 volt 00:11:23.970 --> 00:11:26.610 line becomes 1P8. It really became a universal 00:11:26.610 --> 00:11:28.990 dialect for engineers dealing with digital constraints. 00:11:29.570 --> 00:11:31.809 But the standard doesn't stop at the base value. 00:11:32.129 --> 00:11:34.049 There are also letters tacked onto the end of 00:11:34.049 --> 00:11:36.549 the code for tolerances. Because physical manufacturing 00:11:36.549 --> 00:11:39.970 isn't perfect. Right. A 100 ohm resistor will 00:11:39.970 --> 00:11:42.879 have slight deviations. So the standard uses 00:11:42.879 --> 00:11:46.440 a letter at the very end to declare the acceptable 00:11:46.440 --> 00:11:48.720 margin of error. Like if you see an F at the 00:11:48.720 --> 00:11:51.179 end, that means it's a highly precise part, plus 00:11:51.179 --> 00:11:55.379 or minus 1 .0 percent. And a J means a much looser 00:11:55.379 --> 00:11:58.659 tolerance of plus or minus 5 .0 percent. And 00:11:58.659 --> 00:12:00.460 those letters actually come from World War II, 00:12:00.559 --> 00:12:03.179 don't they? They do. They trace back to U .S. 00:12:03.200 --> 00:12:05.460 military logistics, the Joint Army -Navy specs. 00:12:06.140 --> 00:12:08.899 When the IEC codified the global standard in 00:12:08.899 --> 00:12:11.299 the 50s, the industry was already using these 00:12:11.299 --> 00:12:13.519 military designators. So they just absorbed them 00:12:13.519 --> 00:12:15.820 into the RKM framework. It's just layer upon 00:12:15.820 --> 00:12:18.639 layer of history. But speaking of history, let's 00:12:18.639 --> 00:12:21.559 talk about time travel or rather date codes. 00:12:21.960 --> 00:12:24.899 How do engineers know when a part was manufactured? 00:12:25.769 --> 00:12:28.110 This is critical for failure analysis. And because 00:12:28.110 --> 00:12:30.350 base is so tight, the date code is extremely 00:12:30.350 --> 00:12:32.490 compressed. It's just a two -character cipher 00:12:32.490 --> 00:12:35.269 based on a 20 -year repeating cycle. First character 00:12:35.269 --> 00:12:37.350 is the year, second character is the month. Correct. 00:12:37.570 --> 00:12:39.669 But they couldn't just use the standard alphabet 00:12:39.669 --> 00:12:41.809 for the year codes. They had to systematically 00:12:41.809 --> 00:12:44.490 eliminate any letter that could cause a misfire 00:12:44.490 --> 00:12:46.860 on the factory floor. Right. They skipped G, 00:12:47.139 --> 00:12:50.419 I, O, Q, Y, and Z. The logic there is so sound. 00:12:50.679 --> 00:12:53.879 If you are reading tiny print on a curved surface, 00:12:54.240 --> 00:12:57.820 an I looks exactly like a 1, a Z looks like a 00:12:57.820 --> 00:13:01.320 2, G looks like a 6. O and Q look like 0. Exactly. 00:13:01.360 --> 00:13:04.159 And Y can look like a 4 or a 7, depending on 00:13:04.159 --> 00:13:08.059 the font. So by banning those letters, they drastically 00:13:08.059 --> 00:13:10.899 reduced inventory tracking errors. But the psychological 00:13:10.899 --> 00:13:13.000 engineering gets really crazy with the month 00:13:13.000 --> 00:13:16.159 cold. The October exception. Yes. So the month 00:13:16.159 --> 00:13:18.899 code is just one character. January through September 00:13:18.899 --> 00:13:22.200 are just the digits 1 through 9. Simple. Unambiguous. 00:13:22.700 --> 00:13:25.899 But then you hit October, month 10. You can't 00:13:25.899 --> 00:13:27.799 use 10 because you only have one character slot. 00:13:28.019 --> 00:13:29.700 So you'd think they'd just use letters, right? 00:13:29.820 --> 00:13:32.580 A for October, B for November. But if you use 00:13:32.580 --> 00:13:35.399 A, a tech might confuse the month code with the 00:13:35.399 --> 00:13:38.090 year code. So what does the standard do? It forces 00:13:38.090 --> 00:13:40.549 you to use a letter O for October, which sounds 00:13:40.549 --> 00:13:42.629 insane because we literally just said they banned 00:13:42.629 --> 00:13:44.230 O for the years because it looks like a zero. 00:13:44.450 --> 00:13:47.049 It sounds like a contradiction, but it is rooted 00:13:47.049 --> 00:13:50.350 in pure error correction. Think about it. If 00:13:50.350 --> 00:13:52.669 they had assigned O to January the first month, 00:13:52.750 --> 00:13:54.909 a text scanning quickly would read the O as a 00:13:54.909 --> 00:13:57.440 zero. Right. And since there is no month zero, 00:13:57.639 --> 00:13:59.700 that would trigger a database failure. But by 00:13:59.700 --> 00:14:02.240 making O stand for October the 10th month, it's 00:14:02.240 --> 00:14:04.659 self -correcting. Exactly. If an engineer accidentally 00:14:04.659 --> 00:14:07.740 misreads the October O as a zero, their brain 00:14:07.740 --> 00:14:10.600 says, wait, month zero? That's impossible. It 00:14:10.600 --> 00:14:12.820 forces a cognitive double -take. They realize 00:14:12.820 --> 00:14:14.700 the error instantly. Remember, it's a letter. 00:14:14.799 --> 00:14:17.679 And deduce it means October. They weaponize the 00:14:17.679 --> 00:14:20.200 visual similarity to zero to prevent the error. 00:14:20.340 --> 00:14:22.679 It's honestly genius. So if you see a date code 00:14:22.679 --> 00:14:25.179 like J8, you look up J in the 20 -year cycle. 00:14:25.740 --> 00:14:28.659 Maybe that's 2017, and the 8 is clearly August, 00:14:28.779 --> 00:14:32.639 so August 2017. Or August 1997, because it repeats. 00:14:33.000 --> 00:14:35.159 The engineer has to use contextual awareness 00:14:35.159 --> 00:14:38.000 based on how old the board looks. So what does 00:14:38.000 --> 00:14:40.179 this all mean? We started out looking at these 00:14:40.179 --> 00:14:42.940 tiny cryptic strings on a circuit board, but 00:14:42.940 --> 00:14:46.500 decoding the IEC 6062 standard reveals this highly 00:14:46.500 --> 00:14:49.139 evolved, fiercely error -resistant language. 00:14:49.360 --> 00:14:51.240 It really is. It was born out of the physical 00:14:51.240 --> 00:14:54.019 limits of old typewriters, degrading photocopies, 00:14:54.019 --> 00:14:56.730 and rigid sorting. algorithms and the fact that 00:14:56.730 --> 00:14:59.590 someone in shenzhen someone in stuttgart and 00:14:59.590 --> 00:15:02.769 someone in silicon valley can all look at a 4k7 00:15:02.769 --> 00:15:06.309 component and have total unambiguous agreement 00:15:06.309 --> 00:15:10.289 on what it is it's a monumental achievement it's 00:15:10.289 --> 00:15:12.289 the hidden infrastructure of our modern world 00:15:12.289 --> 00:15:16.509 without the rkm code the globalization of electronics 00:15:16.509 --> 00:15:19.559 manufacturing would have been bogged down by 00:15:19.559 --> 00:15:22.139 endless translation errors and supply chain friction. 00:15:22.320 --> 00:15:25.759 So to you listening right now, the next time 00:15:25.759 --> 00:15:27.080 you have a piece of hardware open and you're 00:15:27.080 --> 00:15:29.879 staring at that green fiberglass board, look 00:15:29.879 --> 00:15:31.620 closely at those components. You're not just 00:15:31.620 --> 00:15:33.320 looking at silicon and metal. You're looking 00:15:33.320 --> 00:15:36.100 at a master class in problem solving. Every missing 00:15:36.100 --> 00:15:38.840 decimal point, every shifted multiplier, every 00:15:38.840 --> 00:15:40.899 skipped letter Z, it's a carefully engineered 00:15:40.899 --> 00:15:43.580 decision designed to prevent disaster and keep 00:15:43.580 --> 00:15:45.799 the world running efficiently. It's a brilliant 00:15:45.799 --> 00:15:48.580 legacy. But it also brings up a really provocative 00:15:48.580 --> 00:15:51.139 thought about the future of hardware. Oh. Yeah. 00:15:51.299 --> 00:15:53.480 The whole reason these three character codes 00:15:53.480 --> 00:15:55.460 evolved was because surface mount components 00:15:55.460 --> 00:15:58.580 got small. But as we move into nanotechnology, 00:15:59.120 --> 00:16:01.080 we are designing parts that are fundamentally 00:16:01.080 --> 00:16:04.039 microscopic. Oh, wow. Right. How will the language 00:16:04.039 --> 00:16:07.580 of engineering evolve when it becomes physically 00:16:07.580 --> 00:16:09.879 impossible to print anything on the component 00:16:09.879 --> 00:16:12.580 at all? That is a wild thought. But I think that 00:16:12.580 --> 00:16:14.889 is a deep dive for another day. Thanks for joining 00:16:14.889 --> 00:16:16.389 us and we'll catch you on the next one.