Embedded - 419: Fission Chips

Episode Date: June 30, 2022

Eric Schlaepfer and Windell Oskay are the authors of Open Circuits: The Inner Beauty of Electronic Components. We discussed the inner beauty of a number of electronic components as well as cameras, photography, writing, preparing samples, and terrible title puns. You can pre-order the physical book and get a digital early release copy at NoStarch.com/Open-Circuits Windell is co-founder of Evil Mad Scientist Laboratory (@EMSL). He and Eric have collaborated before on several projects: The Three Fives Kit: A Discrete 555 Timer  The 555SE Discrete 555 Timer The XL741 Discrete Op-Amp Kit The 741SE Discrete 741 Op-Amp Eric is also known for the Monster 6502, a 6502 processor made up of individual transistors. Eric also writes on tubetime.us and is on Twitter as @TubeTimeUS Sign up for the Embedded newsletter by the end of July and be entered to win one of these lovely prizes: The Three Fives Kit: A Discrete 555 Timer (two) A copy of Open Circuits (one) Transcript A lovely reject from the book, this is the base of a neon bulb from GE.

Welcome to Embedded. I am Alicia White alongside Christopher White. Have you ever wanted a coffee table book with lovely pictures of the insides of resistors and power transformers? With some great commentary about how parts are made? I've got good news. Eric Schlepfer and Wendell Oskey have written that book for you. Hi, Eric. Hi, Wendell. How are you doing? Doing great. Thanks for having me here.

I'm doing great. Thanks for having me back. Eric, you haven't been on the show before. Could you tell us about yourself as if we met at the Hardware.io conference? Sure. I'm an electronics hobbyist, experimenter, and, well, also an electrical engineer. And so I do this stuff for a living, but when I get home, I just haven't had enough, and so I keep doing it. And so I have a little workbench, and I like to tinker with old computers and Nixie tubes and vacuum tubes and all kinds of things like that. And Wendell, I believe you are an evil mad scientist laboratorist? I get that a lot, yes.

My background is actually in experimental atomic physics, but right now I run a company called Evil Mad Scientist Laboratories, where I'm the co-founder. And I mostly design robots for a living, but I also enjoy tinkering with technology. And we've had a lot of intersections with Eric and collaborations with him in a lot of our projects over the years. We'll have more questions about that, but first we want to do lightning round. Are you ready? Oh yeah. Yep. Best focal ratio. Right now I'm thinking about 4.8 because one of the things that I do is I volunteer at an observatory and we use a 30-inch telescope with an F4.8. So that's been on my mind the last couple days eric any any follow-up i kind of like 1.8 that's a good number sanding sawing chopping or cleaving definitely sanding i found that as a general purpose technique it works great for a lot of different kinds of parts.

Sure. I'd have to go with sawing. We saw an awful lot of parts. One of the things I do is a lot of manufacturing work. See, I would have gone for chopping or cleaving, but then I like the destruction. This is more fun, but it may not work as well. That's true. What is the best microprocessor? Well, a 6502, of course. The next question on the list is why is it a 6502? So I guess you're going to get that one too. The reason why is that a couple of years ago, I designed a discrete transistor version of the 6502. So it's several thousand transistors on a very large circuit board. And it's the real 6502 that runs code. The pleasure of seeing that in person. Yes, it was very cool.

Wendell, do you have a favorite microcontroller? Wait, are we changing from microprocessor to microcontroller here? Only accidentally. If we're going with microprocessor, I'm going gonna have to go with the 68 000 because that was my mac growing up which is more fun writing or photographing photographing i would agree with that writing is really hard writing is really hard do you normally start one project or complete a dozen oh wait no that's the other way complete one project or start a dozen. I start a dozen. And instead of just starting one project where you're the pressure's on, like you have to finish it, start a dozen projects.

And if you don't finish 11 of them, who cares? Just find the one that gets you motivated. And the one that you really enjoy the most. And that's the one that you finish. I'd have to say the same for me. I have so many unfinished projects that it's kind of a running gag. Favorite fictional robot. I'm going to go with Spawforth from Mockingbird by Walter Tevis. Wow.

Always got the best answers. It really does. Eric? That's a really good answer. I'm in awe. I think my answer is going to be, Johnny Five is alive. Okay, I want to ask about the book that you have written. But first, I need to bring up something that's very disturbing about the book,

which is, why did you write the book I wanted to write? Except mine was going to be pretty pictures about consumer toys and their hardware. But you made this pretty book full of electronics. Why did you get to do it? And why didn't I ever get around to it? It was kind of accidental in a way. It was just sort of an idea that I stumbled on. And it's related to a technique that they figure out what went wrong. And hopefully I could fix it too, because I really liked what it looked like. And I found a tantalum capacitor inside that had failed. And it was a short circuit, which is how those tantalum capacitors often fail. So I thought, well, maybe I'll just try sanding it in half to see if maybe there's like an obvious burn mark or just something interesting going on inside. Now, I didn't really find anything interesting inside other than the fact that

tantalum capacitors look really cool inside. No burn marks, no nothing like that. So I took a picture of it and posted it on Twitter. And it turns out Twitter really liked it too. So then I started taking some other components and cutting those in half and posting those pictures, and Twitter really liked that. And then at some point, a bunch of people were like, hey, you should write a book. So that's how it started. Isn't it? People say, you should write a book, and you think, huh, that might be interesting, instead of, oh no, run away, run away. Yeah, exactly. How has book writing gone for you?

Writing a book is a really large amount of work. And it's even more work than you think it is. And I'm going to say that even knowing well that you have written a book, and you probably know this too, but even as much work as you think it is, it's that again after that. We're sort of in the recovery stage right now, I guess, because it's off to the printer already. So right now we're still sort of winded from it. But it was really grueling at some parts trying to get it all done by the deadline.

And you've written a book before. That's right. And I was actually on your show talking about it, the annotated Build It Yourself Science Laboratory. So you knew what you were getting into. Eric, this was your first book, wasn't it? Yeah, it was my first book. And I had an inkling that it would be a lot of work. And I was not disappointed. That's a good attitude. I mean, in some ways, it's really great. And some parts of it are really fun and really awesome.

Other parts just turn into a slog when you're trying to edit the same material over and over again. And your brain stops understanding English words and just hears nonsense noises, you just have to take a step back, maybe get some sleep. But then you realize that in a few hours, you got to get back at it again. So what was it like collaborating between the two of you? How did you divide up tasks and stuff? For the writing part of the book, we very much took turns writing in the same Google document. So Eric or I would start with a very rough draft where we put down sometimes just bullet points of what we wanted to talk about, or in some cases, a couple of great paragraphs. And then the other of us would take over at some point, and we went back three or four times on these. And for every single thing that we talked about,

it was really quite a difficult challenge to express what this object is for somebody who has never heard of it, what's interesting about this object for somebody who is familiar with it, and to communicate both of those things to these different audiences in the amount of space that we had provided. And as part of that, we worked with a mock-up of the book where we laid out where the pictures would go and where the text would go, so that we could see how much space we had to describe each object. After this, our editor came through and basically said, now you need to explain these eight things further, which was sort of a difficult part of the process. But we again went through about five more times on essentially every sentence in the book and tried to make sure that we really were explaining the things that we needed to and keeping them in the length. Did you have all of the pictures first or did you have some words and some pictures?

We did this book over a long period of time and a couple of years. And by the time we were actually got really serious about the writing, we were doing only writing. We'd essentially finished all the photography. But for the first year or so we were working on the book, it was really 50-50 writing and photography. And of course, the sample collection and preparation, because there's stuff that we did that never made it into the book because it just wasn't quite good enough. Wasn't quite good enough photography-wise, or wasn't quite good enough photography-wise, or it wasn't quite good enough you couldn't explain it in half a page? Mostly photography-wise, but not all the parts that we cut in half looked all that interesting inside. So there were parts that we took and prepared and looked at them, and they're just kind of boring.

Like what? I'm trying to think of a good example. I have one. I think there were some capacitors oh yeah go ahead uh the glass encapsulated thermistor oh yes so uh do you want to describe eric yeah so it looks kind of like a glass diode except on the inside instead of having a little chunk of silicon it had something that looked like a little chocolate muffin. That was just a piece of, I suppose, material that changed resistance based on temperature. I bet chocolate muffins do that. They probably do. Eric, I think we may need to do

an experiment here. So do you have a favorite picture? Well, I definitely do. Can you share it? Yeah. Yeah, I think my favorite is the cross-section of the cell phone circuit board. Yeah, that's pretty good. It has lots of layers. What about you, Wendell? I have, I guess, two favorites. What about you, Wendell? circuits and the upper ones are wire bonds. And so it's just sort of a magically weird device.

And my other favorite is the vintage calculator with a vacuum fluorescent display. And I love this picture because the VFD itself is suspended in air by all these little welded wires. And then down below it are all these standard components you'd find in a circuit board from that era. And by the time you get to this point in the book, we've already talked about and shown pictures and cross-sections of almost all of those objects down below it in the book. So it just feels like a moment where the whole thing comes together. When I was looking through some of these pictures, I found myself drawn to certain kinds of things. For example, anything with windings. For some reason, just the packed copper cross section is really appealing visually to me. I know there are people with the phobia of that, so I'm sorry if i'm but uh as you were doing this were there things like that where you would discover hey this is this this pattern or this kind of component uh has a certain visual appeal i didn't expect i'd say yes there were many moments like that uh the uh windings of copper in the

cross-section of the small speaker, for example, I thought were really magically beautiful that we embedded the speaker in resin so that we could cross-section it and see those wires sort of floating in air. But the wires were actually one of those things that were hardest for us to cross-section. There were a couple of things we really wanted to get in the book, and one of them was a reed relay, and another was a cross section of the electromagnetic relay. And both of those, when we tried all kinds of different methods of cutting through them, we just couldn't get a cross section through those giant thick bundles of wires that really looked that good. Yeah, and those wires were really, really fine in the reed relay. And so we would go in there

and start cutting it, and then they would sort of splay out the reed relay. And so we would go in there and start cutting it, and then they would sort of splay out everywhere and come apart. And we tried all different techniques to glue them in place, and just nothing really worked all that well. They just tended to smudge together. So if you try to chop something in half, there's a good chance you'll crush it. And if you sand something,

there's a decent chance that you'll let all of the magic dust out. Magic dust? Fine. Pixie dust. You mentioned resin, and I noticed some of the pictures said it was in resin. How did that work? What we did is we had a little vacuum pot that we bought along with some epoxy resin. And so the idea was to take a sample, such as the speaker, and impregnate it with the resin. So in a couple of cases, we had to go and make little holes in different places to allow the resin to displace the air that was in there. And then all of that went into the vacuum pump. And we would pump it down to try and get all the air bubbles out, which sounds easy, but it's actually very challenging. And it took a lot of practice for us to try and figure out how

to improve our technique to the point where we could do that. And then what you do is you let the resin harden. And then you hook it up to Wendell's favorite tool, which is the slow speed diamond saw, and then you start making sections. And so you end up with multiple sections of these, which means you can almost see through some of the things. You can, you can, and that's part of what makes that speaker look so interesting interesting is that what you have is a thin slice where you can see the little individual bits of wire that once formed a coil, but now you just get a little short section of it, and you can see through the entire thing. They were pretty magical looking, although some of the semiconductor pictures, it kind of looked like a circuit in miniature, which I know, that's kind of what it is. But it had all the messy wires.

I didn't expect that. I should have. I know how wire bonding works. But was there anything that surprised you? Something that surprised me was one of the older chips that we prepared. It had... So in every chip, there is a special material,

typically a glue or a conductive adhesive, that they use to attach the actual sliver of silicon to the piece of metal that's part of the case. And we're looking at it, and we realized that someone had placed the silicon in there by hand because we could see scratches left from a pair of tweezers, and we could see that the glue had gotten smudged. And it just really struck home that these early chips really were made by hand. Wow, that isn't something you think about now. I guess I always assumed that they had machines to do it, but that, of course, wasn't always the case. Yeah, it was really a remarkable

find. This was on the MU-A702 integrated circuit, which was the very first analog integrated circuit to reach the market. So there was the resin preparation. How else did you prepare things so that you could look inside them? The vast majority of the actual cutting in this book was done by Eric by hand with sandpaper. Not even a Dremel, but actually just sandpaper? Sandpaper, yeah. It gives you a lot of control, and I got really good at the technique, but especially things like the chips, if you're going to sand it down and get really close to the die, or if you want to get really close to a feature, it just provides so much more control because you can stop sanding and inspect it under a microscope and then change where you apply pressure on the part.

So if you need to change the plane of the cut just slightly and make little adjustments, it's just so much easier if you do it by hand on sandpaper. Of course, it does take a lot longer. Some of those samples had a good six hours, eight hours worth of sanding work in them. I was going to ask. Yeah, that seems like you're not going to ask if your arm got tired. What did you work down from a coarse grit to a fine grit or just start with a fine grit and stay there or it depends on the sample so a lot of the samples i would start with a coarse grit and start sanding and then stand too far and look at

it and throw it out and get another part and try again and so i get a little preview of of what i was going to find in the part if i did end up accidentally destroying it but by and large yeah i would start with the coarse grit and then kind of work my way up to finer and finer grits, up to some final polishing, which could take quite a bit of time. What'd you use for final polish? Again, it depends on the sample, but we, in some cases, we went up to 10,000 grit. And so we'd spread a little bit of isopropyl alcohol on top of the sandpaper, and Wendell showed me a specific way of doing it, using a figure-eight pattern to avoid adding new scratches. The challenge is when you're at that point,

when you're doing such a careful polishing job, is you don't want any foreign debris to get in between the sandpaper and the part that you're working on, because then that's going to add a deep scratch. You'll actually have to go back several gr between the sandpaper and the part that you're working on because then that's going to add a deep scratch. You'll actually have to go back several grits of sandpaper and then essentially start over. Did you create a clean room for this? No, no.

This was just either in my little shop or in Wendell's shop. So depending on the nature of the thing and how things were looking, some of the samples were ending up with 300-grit sandpaper and some were ending up with a 10,000, but probably 1,000 to 3,000 were the most common final points. The cables section where there were, I don't know know the coaxial cable was one of them but there were a few other cables that had cables inside of them in different patterns how did you decide which cables would be the best to put in the book

with blood and tears yeah trial and error blood sweat and tears i have a box of like half a cable like just full of cable halves yeah on several occasions erica presented a perfectly polished piece of cable and it was like one centimeter long i'm like eric i can't photograph this so we uh there was a lot of considerations about what makes a good photograph and about what makes an interesting sample. And you do have to do both. It can't just be one or the other. That's right. What makes a good photograph for this? That's a really interesting question. And there's so many different ways that we took these photos and present them. For example, we have a picture of a USB cable, a USB-C cable

that has these what are called micro coax bits inside of it for transmitting data at relatively high speed, 10 gigabit per second. And for that one, we had to embed a piece of the cable in resin and then slice it and then polish it and photograph it end on in order to be able to see those things in their detail. For other ones, we sort of dissected them. For example, we have a laptop power cable from a MacBook Pro that we dissected it from the outside with an X- exacto knife one layer at a time to reveal the different layers such that you can see them as sort of a three-dimensional object. But it really depended on what the type of cable was, what we're going to do to be able to see what that structure inside looks like. And for most of these, there are other ways that would work as well. So there's

just, there's some degree of trying to keep things different per page and some degree of trying to make things as clear as possible. When you start with something, a new object that you haven't looked at before, that you haven't cut in half or otherwise prepared, you try a bunch of different things. Like we would, you know, strip a cable back and see what it looked like inside, maybe just slice it straight across. And usually something would pop out. Like you would look at it and you go, okay, this is definitely going to be a good photo. Whereas maybe another way to prepare it, you'd look at that and say, you know, honestly, it's not that interesting. It looks too much like this other sample that we did, or it just doesn't look that appealing compared to doing it this way. How did you decide what would go in the book?

With a very large spreadsheet. Very large. That wasn't the answer I was expecting. Yeah, we were very organized about it. We have this giant spreadsheet with all these entries for each sample, and different columns discussing different aspects of each sample. And so there were a whole bunch of them that we decided weren't quite good enough and got a lower rating. And those went down at the bottom. And the stuff that we really liked and thought should go in the book went up on top. How did you, this is a dumb question,

but how did you decide when you were done? Like, this is enough components. We actually had to pull out a bunch that when we got to the point where we were starting to look at what our page count was going to look like and so on, we went through the thing, went through this list, this spreadsheet list, and we went through and talked about them. And we pulled out maybe 10 or 15 components that were done, photographed, and we had assumed were going to be in the book, but they just weren't the strongest ones. They just, for whatever reason, weren't as clear or compelling as the others. And this was really like pulling nails to do this to take these works that we'd already completed out of the book. But after it, we felt like what was

left was actually stronger. So I kind of feel good about it. Yeah, it reminds me about, it kind of reminds me of writing. One of the most difficult things in writing is knowing when to erase something. And sometimes you can have a much stronger piece of writing if you delete a sentence or a couple sentences or even paragraphs. But it's really hard to do because you put all that work into creating it in the first place. And so we spent a lot of time on those samples, and they didn't make the cut. A good example of one would be the SFP cable. Eric had this amazing SFP cable, which we took a cross-section picture of, and it looked incredible inside. And we wanted to get a good photo of the connector that it goes with. And that just never came together to look as good as it should. SFP is a cable used in data centers typically.

So you run essentially networking signals on them and they connect multiple routers or servers together. Was there a level of complexity that you had? Was there a line that said, okay, we don't want to go beyond this level of complexity? I wouldn't say that we had a complexity line. We have some extraordinarily complex things in the book, but we did have a rule that the book was going to be about components, not about systems. And circuits, like, work still components, but just barely? I'm sorry, I'm not sure i understood that question i mean you have some circuit boards in there as well those aren't a circuit board as a component

yeah yeah it shows up in the bill of materials just like all the rest of the capacitors and resistors and everything else all right i'll allow it because i don't know any better but it is beautiful yes but it's so beautiful yeah I'll allow it because I don't know any better. Yes, isolation amplifiers walk on that line. But it is beautiful. Yes, but it's so beautiful. Yeah. So the title of your book, which I'm not even sure we've said yet, is called Open Circuits. And that's a pun, right?

And whose fault is it? It's both of our faults. I almost want to take the credit, but it may have been a mutual thing. I think I came up with that one, but we had so many different titles. And I have to say, the hardest part of the entire book, by far, was figuring out the title and the subtitle. It was extraordinarily difficult. How many titles did we look at? I thought that you would appreciate me reading a list of some of the worst title ideas that we came up with. Yes, please.

Eric, may I? Please. Okay. Digital Divide. Fission Chips. That's F-I-S-S-I-O-N, circuit splitty, chips apart, chip chop, cut a part, parted parts. Oh, cut apart? Yeah.

I get it now. Okay. Sorry, I'm two or three years old. Electro cuts. Split parts. Ooh, cut apart? I get it now. Okay. Sorry, I'm two or three years old. Electro cuts. Split parts. Yeah, so most of them were sort of bad puns about cutting about electronic parts. I don't know.

Fish and chips. That one really appeals to me. I think you ought to call up your publisher and say, we've reconsidered. Now, these aren't the only bad ones we came up with. There's like a longer list, but I thought these were particularly impressive. But once we came up with the open circuits, it really felt like it fit because it's an electronics term, but it also signifies, hey, look what's inside this that's open. And also sort of talks about opening things, cutting them in half. We kind of wanted

to have a title that explicitly talked about cross sections, but it was really hard to work that in in such a way that worked well. There were a bunch of books when I was a kid, incredible cross sections of stuff. And it was usually of like, I don't know, Star Wars ships and random things and machinery. And this kind of reminds me of that, except it's real things. And in many ways, very serious. And that's why I think one of the reasons I like it a lot is because there's a childlike aspect of it, but it's also almost a reference book at the same time. I think Eric was very strongly influenced by those books. There may be an influence, yeah. I think in general, we're writing the book for people who are as curious as children, regardless of their age.

So if you've seen a part and you're curious about what's inside it, then this book is for you. Do you think some of the people and companies who made these parts know what they look like inside in this manner? Quite a few of them do. One of the things I mentioned at the beginning of the show was that cutting something in half and preparing it like this is a technique that's used in failure analysis. So a company that's selling a product, if that product fails, especially a component, then one of the things that they do to figure out why it failed is to cut it in half, or if origami, unfold it and look at the crease pattern. But it's a destructive way of handling something you've built, and there's nothing similar in music.

I can destroy my music. I guess it depends on the genre, right? Because some musicians would take the guitar and they would smash it on stage, right? I don't think that tells you about the quality of the music directly. But going back to the components, when I think about capacitors, I mean, I just think about the little symbols because they don't mean that much to me as a software engineer. I know that there are electrolytic and Tadalam and some other things.

How important is it to know the physical construction? Is it or is it just about being pretty and neat and curious and amazing? Well, you can certainly use it without understanding exactly how it works, and there's nothing wrong with that. If you do understand how it works, there are some things that kind of fall into place about the name of the capacitor and why it has the properties that it has. I think the best example of that is the electrolytic capacitor. And you might wonder, why is the electrolytic capacitor polarized? Because the capacitor is just two parallel plates.

Why would the polarity matter? And it took years before I figured this out. In fact, I don't even think they taught it in engineering school. But the reason is that the electrolytic capacitor has a conductive liquid inside. And it's an electrolyte. It's in fact, it's the same kind of electrolyte that, you know, could be like saltwater or the same kind of electrolyte that you might find in a battery. Electrolytes, wait a minute, capacitors are made of Gatorade? Essentially, yes. In fact, I may do an investigation on Twitter where I experiment with Gatorade and capacitors. So stay tuned. Maybe a Red Bull one would work better.

Possibly, yes. I mean, I could try it in batteries too. Maybe a battery works better with a different brand of energy drink, right? So anything that's got those, that's got that kind of an electrolyte formula in there is going to work as a capacitor electrolyte. If it conducts electricity, then it forms one of those parallel plates in the capacitor. And that's also what polarizes it. I want to see you make a battery with one of those three hour energy drinks that and i wanted to last three hours i need to start getting three hours now i'm wondering all kinds of things like gin and tonics

30 year old scotch i mean maybe maybe that works really well i don't know chemical properties are probably all wrong were there um you you had mentioned that you had like boxes of trial and error parts were there any parts where you didn't have a lot to to destroy and kind of felt like uh better get this right the first time or the second time because we only have two or three yeah uh wendell i think there was one part that was pretty expensive that we cut in half and i unfortunately i can't remember which one it was the one i had in mind was actually the cathode ray tube oh yeah we cut a cathode ray tube that was the viewfinder crt from a 1980s JVC camcorder. And it's actually made by Panasonic.

And it's this marvelous little thing with a main tube about the diameter of a pencil. And we went through probably five of these getting it just right. But there aren't that many video cameras you can get, right? We actually came across a whole bin of these for like $10 each at the Excess Solutions warehouse. When the way things work came out when I was, I don't know, younger, one of the things I just kept thinking about it was if I could take this back in time, it would be so amazing.

And I thought that about your book. If I could take this back in time, I could show people how to make these components that were so hard to invent. Were there any things that you thought about like that? I wouldn't say directly. So one of the things that I kept finding myself doing in, especially in writing the descriptions of things was really having to work hard to understand how something works better to be able to write a description of it.

And an example would be the giant magneto-resistance hard drive head. That's not a sort of thing that most of us will think about or even know how that works, but we need to be able to write a description of it that is going to make it make sense to a casual reader. And it's a challenge to understand something well enough to be able to explain it in a couple of sentences in a way that is both accurate enough for an expert to basically shake their head and for a general reader to get some idea of what's going on. It's a tough line. I mean, popular science is a lot different than technical books because you do have that expert will say it depends for everything. And a high school student without, you know, a lot of depth in this area will just look at it and go, I don't understand why that's even a thing or if it's cool or not. How do you balance those? I think if it looks cool, it goes into the book.

And we try to explain it as best as we can. But given that the focus is on the photographs rather than the text, it's going to be imperfect. But honestly, I think as long as it looks cool and people look at that and kind of appreciate it for being an art object, then I've met my goal. And if I can explain to someone and they can understand how it works, that's kind of a bonus on top of that. How big is the physical book going to be? It's about the size of a book. Okay. Oh, really? Surprising. It's eight by 10 inches and 304 pages, and I don't know what the physical thickness is. 304 pages. No wonder you had to cut some. And these are all going to be full color.

Yep. Let's see. And you can get a copy from No Starch. That's where we got our early access digital book. Where else can we get copies? The book is sold by No Starch Press. So at nostarch.com, you can pre-order it, get the ebook and physical book. It's also, No Starch has distribution through Penguin Random House worldwide. So it will be hopefully appearing in bookstores in the US starting around September 2022 when the physical copies start to arrive. But if you're elsewhere in the world, you can ask your local bookstore to pre-order it for you. And then there are also various online stores. So essentially everywhere books are sold,

we'll have access to be able to get this for you. And you can start ordering it now from some folks. And it looks like the publication date is supposed to be September 27th. So don't start on the 1st of September. It would make a really good Christmas present. In fact, we're probably getting one for your dad if he doesn't listen to this show, right? Yes. You're going to hold this episode until just after Christmas to make sure this is a surprise, right? How did retro computing fit with this? It seemed a little bit of a fork in the road for me, and I wasn't quite sure how you made them go together. The book version we have now wasn't laid out in a historical

manner. It was in more of a complexity manner. Yeah, we puzzled over that because one of the things that we thought about at first is to say, well, what if we went in chronological order? Like, these are the oldest components, and then we'll go newer and newer and newer. And it wasn't quite as cohesive. It just didn't come together as neatly as categorizing the parts the way that we ended up doing it. As far as retrocomputing, I'm not sure if that answers your question. Why did you include that? Why didn't you just say that isn't, those components are old, we don't need to worry about them? Oh, because they look interesting.

All right. Your criteria is really easy, Eric. Okay. I mean, if it looks cool, I mean, it's going in the book, as far as I'm concerned. All right. Your criteria is really easy, Eric. I mean, if it looks cool, I mean, it's going in the book, as far as I'm concerned. Of course, it has to be an electronic component, because that's, you know, right there in the book. And it does have retrocomputing to some extent, but a lot more of it is just our excuse to be able to put in things like vacuum tubes and Nixie tubes and the CRT. And these are some of our really coolest looking electronic components. And it felt more natural to set them aside to say, this isn't actually something we use all the time now. This isn't your everyday component. Here's some vintage stuff and keep it in its own separate chapter.

I use 12AX7s all the time, so I don't know what you're talking about. And they'd have to take that section out of the book with the 12AX7, which is not allowed. It has to stay in the book. And that is exactly our reasoning. Yes, that makes a lot more sense now. Eric, you mentioned making a 6502 out of transistors. Yes.

Why isn't that a kit yet it turns out we're in the middle of a global supply chain shortage and it's really hard to buy things including transistors oh come on how many could possibly have thousands it's like a real and a half of transistors per board yep yeah it adds up really quickly uh i think we'd be remiss if we didn't talk a little bit about the photographic process. What, you take a picture? Yeah. Maybe you have a little light box or something. Would one of you please describe the process of doing these very intricate photographs?

Some of them are very macro. That seems extremely challenging. Yeah. So I've been doing photography for a very long time. And I kind of walked into this thinking, hey, that's no problem. I have $1,000 macro lens, I can do this. And I wasn't quite prepared for what I had bitten off. We did use that lens quite a bit, but I actually had to get another macro lens that was even tighter in focus. And we had to use focus stacking for a lot of the images. That's where you take multiple pictures and then, through the magic of computers, make them a better picture? That's exactly right. So one of these key things that you probably know about macro photography

is that you only have a very shallow depth of field, that you only have a very small amount that is in focus at any one time. Even as best we can do on that macro lens at our tightest focus, we are going to get only a quarter millimeter or so at a time in focus. And if you're looking at an object that is maybe as a depth of 10 millimeters or 15 millimeters that you want to get in focus, you have to take a bunch of photos and combine them. We used a product called Helicon Focus, which is a focus stacking software. And we built a custom robotic focus rig that actually moved the camera in quarter millimeter increments, takes a whole bunch of photos, and then we feed those into the software. Wow. I thought of asking if you'd come up with any custom stuff, but I didn't think that was necessary, but apparently it was.

There are some off-the-shelf solutions we could have used, but they didn't really appeal to me for various reasons. And we, just in the course of our normal business here, have some robotic parts that can be used to make things like that. Did you use one of the Axie draws to mount the camera to it, and then a custom shutter release cable that interface to our hardware, and a bunch of software written and processing to drive it all. In fact, there's a very nice picture of it in the book. Just don't ask us how we took a picture of the camera. Yeah, I did appreciate the afterword where he described some of the processes. I think that was a really, really good idea to include because it's, you know, the pictures are so, how did, you know, they invite, how did they do that?

And I think including that was really a good idea. One of the things we thought was important to say was that these are really pictures, not renderings. Yeah. This brings up a listener question from Brian. Virtually none of the items you took pictures of were designed with beauty in mind. How do you find the beauty in each item and express it in the photograph? I think I touched on it a little bit earlier, but a lot of it was trial and error. And so I would just go through all the parts that I could find in my parts bin or parts that I could find at Wendell's shop or at the local surplus store. And I would just cut it in half or sand it a certain way and kind of look

at the results. Wendell did some of the sample preparation as well. And we would just try a bunch of different things. And occasionally we would find a part that was boring and we would move on to a part that maybe was more interesting. Or we would try cutting it a different way. And then sometimes it would really pop out and we would say, well, that's really neat looking. Wendell, same question. This is a really interesting question that a lot of the time we didn't really know what was inside. And you can know when you open up a transistor 2N quadruple 2. You open this up.

You know that there's going to be a little transistor die. You know there's going to be two wire bonds. But do you really know what it looks like inside? Do you really know what the shape of that transistor die is? And do you know what colors it will be? You really don't. And so, so much of this was really trial and error. And I have to say, Eric did an immense amount of preparation work on samples that we ultimately decided were just not really quite the most interesting, that we just sort of had to make an editorial decision that if we're going to have only so many pictures we can put in this book, this isn't going to be

one of those. But it's not about complexity or even about technical interestiness. There is an aspect to it that is artistic and beautiful, but that's not what we think of when we think of electronic components. We think of functionality. At what point did you realize that it wasn't about the functionality? I think we kind of knew that going in. I was thinking about one of my other favorite pictures from that set is the dip switch cross section. And it's one of my favorites because it's not really complicated. It doesn't have all the layers and components and traces and copper and all the crazy things going on with the cell phone cross section. But it's just really, really simple, really clean. There's a lot of very basic geometric

shapes in it, and it's really colorful, and it just kind of pops out at you. You look at that, and you go, wow, that's really, really pretty. And then you look at it again, and then the engineer part of your brain looks at it and says, oh, look, you can tell that it's a switch and that it's open, and then you can see how the little ball moves and the little spring moves, and then you understand how it works. I think one of my favorite sections of the book is the electromechanics because there are so many of those little switches and pots and things with a moving component where I guess I had kind of always wondered, how do they work inside?

Because when you do a dip switch, there's that satisfying little click and stuff, and it was really neat to see, oh that's how that works and it would never would have occurred to me to open one up um and find out but but seeing them like that was really kind of gratifying it's like oh that that's really clever there's clever bits in these things i remember taking apart a switch and realizing that it was made of springs. And suddenly, debouncing made so much more sense. One of my favorites from the electromechanics section is the micro switch, which is this one that you may not think about or even know what's inside. But it's the switch that's on every computer mouse for your mouse button.

So you might use one of these all the time. And you open it up and look inside, and it may not be that beautiful, but it's sort of as beautiful in how it works, in its elegance of simplicity of how the thing actually functions. And that's one of the places to find beauty, is that elegance. And the weird simplicity that you didn't expect, but now that you look at it, it makes so much more sense. Absolutely. Another listener question from Exploding Lemur. What are some of the things you wish you could have cross-sectioned but couldn't due to cost availability or safety concerns? Oh, I got one. I actually was able to successfully cross-section this,

but there were some logistical issues that meant that we couldn't really include it as a subject in the book. And that is a button battery. So I took a button battery and I was actually able to cut it in half. Of course, I was very careful because I understand that there's lithium in it and all of that. And so of course I have to take all these safety precautions. And yes, while I was cutting it, it got hot because you can't avoid not shorting these things out. And I ended up with a pretty decent photograph and you can actually find it on Twitter. That was one of the items that I put up there. The problem was, is that it oxidizes so quickly, you can't pose it for a really good studio photograph.

So maybe there's a way to do it in like some sort of oxygen-free atmosphere. But it started getting really complicated. What about you, Endel? So I have a giant list of things that we wish we could have put in the book for one reason or another. And some of those were ones that we just couldn't find a good sample of. One of them is a thin film resistor array, like from a multimeter. And we didn't come across one that we felt comfortable removing from its application. But it's one of those things that I've seen pictures of, and I wish we could have included close-up photographs of. There are a few others like that. I wish we could have taken an

IBM Power 5 server CPU and cut it in half to show the insides of that or microwave circuitry. But, you know, we couldn't actually get our hands on everything we wanted to. And 300 pages. Yeah. Probably should have been aiming for a bit lower in page count, actually, too. Were pogo pins on the list, or are they just not that interesting? That's an interesting idea. I hadn't thought of that. We should add that to the list.

Okay, go on. Go on on second edition if we ever lose sense of how hard this was. I'll tack it on the bottom here. Pogo pins. Okay. You also didn't do super cheap electronics, which is an area that I like because of my history with consumer toys. The electronics you get out of a $10 toy look very different than these pictures. It's not pretty.

And yet there's still so much inside them. And I wonder if there's a difference. Just make your book. I'm not going to. We do have some things that are definitely from the lower end electronics. And for example, we have the circuit board used on the LCD display. We have some things with the glob top packaging. We have a wristwatches circuit board.

And those things are always designed cost in mind. There's also a bunch of others that we took photographs of that didn't get into the book. For example, we had a television remote control, and that is one of those things with the absolutely cheapest grade of electronics there is. There's the not even FR4. It's a paper phenolic base. It's single-sided. The contact pads are not gold plated. They are printed carbon. The traces on the board, I mean, they're just ugly. Everything about this board is ugly. And I couldn't really find good ways to get photographs of that that didn't look ugly. Couldn't make it like one of the dogs that's so ugly it's cute. That is true.

They are often lacking in the elegant simplicity, beauty sort of thing. I noticed a cameo of the Giant 6502. Were there any other cameos that snuck in? Yeah, actually, there were a few. Let's see. One, there's a circuit board that is the controller for the hot wax dispenser for our egg bot product. So you can do this traditional Ukrainian style pisanky, which is where you decorate eggs with multiple layers of wax, resist and dye.

And we have a robotic method of doing that. And the control board for that has the same type of trimmer potentiometer that we did a cross-section of. So I showed a picture of that circuit board. There's also our Meggie Jr. RGB, which is an old handheld game kit that we designed a very long time ago. Oh, don't forget a bunch of those photos were of circuit boards out of my vintage computer collection oh yeah so they're a bunch of amiga circuit boards and uh some ibm circuit boards and stuff in there apple 2c apple 2 apple 2c yeah exactly what other collaborations have you done i know you have a couple of kits at EMSL, but not the 6502.

Not yet the 6502. The two primary collaborations that Eric and I have worked on are the 555 and 741 kits. We have made both soldering kits of these in both through-hole and surface-mount versions. Which actually, this is a good time for me to say we're going to be giving away two of those kits and one of Eric and Wendell's books. And to play, you have to sign up for the newsletter for sometime in the month of July, and at the end of July, we will pick winners out of our newsletter followers. Okay.

That's what we agreed on, right? That's the plan. No random numbers? No random numbers. Okay, just you have to be... Three random subscribers to the newsletter. Okay. We'll pick out of virtual hat.

Cool. What are you most excited about for the book? What do you think will happen? What's already happening and what I'm thrilled every single time it happens is when somebody opens the book and says, holy crap, I didn't know that that's what this thing that I've always used looks like inside. That's the magical moment for me. Eric? Yeah, I would, I would definitely agree with that. When someone sees one of those photos of the cross section, you know, something that I posted on Twitter or maybe something in the book, and I just see the reaction of a person who looks at it and says, oh, that's how it works. That's how it's made inside. And you can kind of see the carry bit propagate

through and then they suddenly have a much better understanding about, you know, whatever the component was or something. I really enjoy seeing that. It is a lot like revealing the magic tricks and how they work to me. Going through this was like, ah, it felt like reading one of those, you know, magic books. It was like, like oh this is how this trick works okay you know it didn't didn't make sense from the outside it was just you know this magic thing but now now it all makes sense the same kind of feeling um i have a question for wendell that's not really related to the book but it was brought up by the book oh uh and maybe eric you know one of you knows so the trim pots uh they all have these one of you knows. So the trim pots. They all have these,

one of the coolest things about the trim pots that I noticed, and basically all of the, I think some of the crystals, oscillators and things, they have these little sections that are laser tuned. So they can trim the length of the important bit

to just get it to the precise value that it needs to be. Who trims the trimmers? Is this because of my background in metrology that you were asking? It is. So one presumes that ultimately each of these devices goes through a stage of testing and measurement on its way towards having its package sealed up, where it has a laser-controlled device or a computer-controlled device that cuts with a laser to trim the amount of resistive material just so until the resistance gets just high enough that it is within the specification. And that resistance measurement

is made by mist-traceable hardware that ultimately we can say is a reliable number to within a certain amount of accuracy that the company can guarantee for us. One of the neat things for me to realize when we were looking at those different resistors and things was to really recognize that when a resistor says this is a 5% resistor, what they really mean is that not that they've measured it as within 5%, but this is made in a process that typically is measured it as within 5%, but this is made in a process that typically is going to give within a 5% that that crappy cut on the carbon film resistor outside just gives you a 5% value. That's all it does. Yeah, it's, it's very interesting to see how things not not even how things work, necessarily, but how the process is involved in making things

and the compromises and some of these components inside them are like oh yeah it's a you know it's a coil of paper that's chopped up and hope for the best and most of the time it works for the best so something that really surprised me about the earlier components that we took apart, you know, stuff from like the 1920s and kind of that era, was just how different the materials were that they used. I guess your comment about the coils of paper kind of brought that to mind, but you think of the materials that they used back then, and it's, you know, mica capacitors or paper, phenolic, you know, early early early plastics or rubber and stuff like that but you look at the more modern devices and there's a lot more synthetic

materials it's kind of interesting to look at those and compare them when we were offline um one of the things wendell said was that he had to get a new camera for this process. What were you using before and what was the new camera? So I started the project with a Canon EOS 7D, which is 10 years old or so. And it's a digital SLR. It's been a great trooper. It has earned its keep, no question. We upgraded to a Canon EOS R, which is a mirrorless camera. And it was, I needed to get a new camera for a few reasons. One was I just wanted to have a few more megapixels for trying to do some of our really detailed photography. But I also sort of realized this is the right time in the lifespan of the camera to upgrade. I didn't really expect the mirrorless part to be such a big transition. But in retrospect,

the fact that it is mirrorless is the single most important thing about this new generation camera, that it's able to run the sensor continuously to give a little AR representation of what's in focus, to be so quick with its shutter, to be able to mount lenses so much closer with their front end to the sensor. There are so many things about that change that really are a dramatic revolution in how cameras can be constructed. Why did I ask? Chris is here just looking so excited.

He's just, oh, my God. He hasn't been this happy all week. Does Chris need a mirrorless camera? Fine. Finish selling him the camera. Which one should I get, Wendell? I have a bunch of EF and EF-S lenses, so I can't probably use all of those. Why? What did I?

The one thing I'd say is if you do get the camera mirrorless, be sure and get the Canon brand adapter for your lenses. Gotcha. Poor Alicia. Christopher, do you have any questions? I do. Will you be selling the sanded-off parts from the Nixie tubes in little vials and calling it Nixie dust? We will now. All right.

That's my final question. So Nixie tubes are actually filled with a mixture of gases, including neon, obviously, but they also have kind of a blue glow in them typically. And that blue is from mercury that is added to improve the lifetime of the devices. You don't actually really want to be handling the individual electrodes from Nixie tubes all the time. All right. Are you going to be selling any of your slices? Slices? Of the components. We were not planning to.

However, we have thought about doing maybe a little tiny exhibition where we put a bunch of the objects in little display boxes and maybe provide a microscope or some magnifying glasses and let you look at these with some of your eyes. It would look very cute. It would be like a micromuseum. Yeah, I was about to say. That's very cool. Eric, do you have any thoughts you'd like to leave us with?

Sure. People talk about the ABCs. And so the ABC I'll leave you with is Always Be Curious. I thought you were going to say Always Be Cross-Section. Well, that too. Wendell, what about you? There are jewels hidden just under

the plastic covers of so many things that you own and you should totally look inside. Our guests have been Eric Schlepfer and Wendell Oskay, authors of Open Circuits. You can preorder the physical book and get an early digital copy now at

nostarch.com slash open dash circuits. Links are in the show notes, of course. Thanks, Eric. Thanks, Wendell. This was really fun. Thank you both. Thank you. Thank you to Christopher for producing and co-hosting. Thank you to our Patreon listener

Slack group for some questions. And of course, thank you for listening. You can always contact us at show at embedded.fm or hit the contact link on embedded.fm. And now a quote to leave you with. I think Ansel Adams is appropriate here. You don't make a photograph with just a camera.

You bring to the act of photography all the pictures you have seen, the books you have read, the music you have heard, the people you have loved.