A decade after graduating college, Stephen finally did a differential equation for his job! That is some real engineering I tell you what.
The PinoTaur has reached production status but not without supply chain issues..OF COURSE! Bonus discussion about thermal management for PCBA.
Is there a statue of limitations on open source hardware projects? This week, Stephen and Parker dive into what open source means for both of them.
Rapid Fire Opinion
Parker is an Electrical Engineer with backgrounds in Embedded System Design and Digital Signal Processing. He got his start in 2005 by hacking Nintendo consoles into portable gaming units. The following year he designed and produced an Atari 2600 video mod to allow the Atari to display a crisp, RF fuzz free picture on newer TVs. Over a thousand Atari video mods where produced by Parker from 2006 to 2011 and the mod is still made by other enthusiasts in the Atari community.
In 2006, Parker enrolled at The University of Texas at Austin as a Petroleum Engineer. After realizing electronics was his passion he switched majors in 2007 to Electrical and Computer Engineering. Following his previous background in making the Atari 2600 video mod, Parker decided to take more board layout classes and circuit design classes. Other areas of study include robotics, microcontroller theory and design, FPGA development with VHDL and Verilog, and image and signal processing with DSPs. In 2010, Parker won a Ti sponsored Launchpad programming and design contest that was held by the IEEE CS chapter at the University. Parker graduated with a BS in Electrical and Computer Engineering in the Spring of 2012.
In the Summer of 2012, Parker was hired on as an Electrical Engineer at Dynamic Perception to design and prototype new electronic products. Here, Parker learned about full product development cycles and honed his board layout skills. Seeing the difficulties in managing operations and FCC/CE compliance testing, Parker thought there had to be a better way for small electronic companies to get their product out in customer's hands.
Parker also runs the blog, longhornengineer.com, where he posts his personal projects, technical guides, and appnotes about board layout design and components.
Stephen Kraig began his electronics career by building musical oriented circuits in 2003. Stephen is an avid guitar player and, in his down time, manufactures audio electronics including guitar amplifiers, pedals, and pro audio gear. Stephen graduated with a BS in Electrical Engineering from Texas A&M University.
Special thanks to whixr over at Tymkrs for the intro and outro!
Welcome to the macro fat engineering podcast. We're your host, Parker, Dolman
and Steven Craig.
This is episode 205. New year's edition.
Whoo. In a few hours,
and a few hours, it will be 2020.
Well, you will be listening in 2020. Yes, we are recording in 19.
Yes. Are you one of those 2020 is the new decade or 2021 is the new decade.
I'm the I'm the person that a decade is a rolling window of 10 years. So you can choose when it starts. Like that? No, honestly, I'm one of those people where they get it like, in my opinion. Yes. 2020 is a new decade. In my opinion.
I would agree. Yeah. I actually agree with both those statements.
I think it's cleaner if you just say 2020 is the new decade. Yeah, yeah, whatever. I mean, who cares really?
This year, we have perfect New Year. Glasses. Because you have two zeros look out of?
Well, okay, but I guess the two has to be in between you're like where you're
one of the bridges. Yeah,
I think 2000 was like the best 2000 was the best.
or actually any of the arts, right? Yeah, yeah. It gets any the arts right. Is that where we call them now in the arts is 2000. Audience and nine. Was that? The audience? The audience? Yeah. Well, hopefully we bring in the roaring 20s back. Or not
what the mega venturing podcast all by ourselves.
Yes. All by ourselves. Yeah. And our amazing listeners
with a beat jazz and those new kids dancing.
Yes. Yeah. I expect you to wear a flapper dress next steps. I'm the flipper.
I guess I'm the one with the longer hair.
Yep. All right, let's get started. Actually, I want to say one more thing. I wanted to thank all listeners this year for listening to us growing the podcast making it better. And if you haven't listened to it yet, we did do a Star Wars episode last week. And if you've watched episode nine, go listen to it. It's a lot of fun. Steven, I very enjoyed doing the Star Wars Episode. So get those download numbers up.
We actually we look forward to the Star Wars episodes. And we this one we were talking about it in summer. Yes. I mean, like talking about it not planning obviously,
that we were planning topics?
Well, yeah, I mean, planning topics like in other words, we're drinking beers would be like, how great would it be if we talked about this? And you know, things? That's true yesterday? I was so caught planning. Yeah, sure. Sure. Sure. No, it's something that we look forward to every year for sure. And I look forward to the fact that there will be a Star Wars episode next year for sure.
Yes, I'll put this way if salespeople can call golfing business, we can call drinking beer and come up with ideas planning.
Oh, well, it's going on my expense report, then they yo. Alright, let's get going. What's uh, what is up, Parker. So
today, which is what we're recording this episode, the 31st we launched a new PCB specification update that Mac fab. And this is like a long time coming. We've basically instead of the normal kind of PCB tab we used to have for specifications which had like layer count and how thick you wanted it and stuff like that. It now has a lot more stuff in it. You can do stack UPS events via management. So like you can do blind buried vias, you are a logo control surface finishes. What else is there in there? Like copper weights, you can do custom copper weights, all that stuff. It's kind of we revamped the entire PCB specification page. So go check that out. So we basically also expanded like how many specifications we can like quote automatically. So we've been working with our like PCB vendors like nonstop for the past couple months to get that going. But there's still some things in there that like, when you select them, it says when you need a custom quote, but so now you just click a button and like, lets us know that you need a custom quote, so it's kind of cool.
So it's been a wild gosh, probably six or so months since I've logged into the Mac Feb interface to go look at a PCB. So I pulled up my macro amp PCB that I ordered from and just out of curiosity, so there's there's a looks like to me there's a new button on the bottom Right has the microphone logo. By the way? I'm not I'm totally not trying to make this like a sale for backer fab. I'm curious. I'm absolutely curious here. But there's like, that's cool, because like, if you click on that there's like, all kinds of stuff about you can go to the Knowledge Base.
Oh, yeah, that's right. That's a new thing that Joey, who's our product manager, I want to say is his title. He put that in there. So it links to our knowledge base. So like, it's context sensitive. So like, if you're on like the bill materials page, it will like, if you click that button, it will have information about the bill of material page. That's like, pulled from the knowledge base.
Yeah, that's super nice.
Yeah, this PC specifications pages, just launched like, about 45 minutes ago.
Well, okay, here's, previously, if you clicked on the PCB specifications, you would get, like, pulled out and stuff about just like, here's my layers and things. And this actually takes you to a, I mean, it's still the same page, but it takes you to a different view. That's full page here. That's cool. Because, okay, so I'm looking at this. And there's, like, you can select the standard or extended or all this other stuff. And then it actually gives a description of them, which is nice, because previously, it was just like, which one do you want? You had to go to the knowledge base to find it out?
Yes, exactly. Cool. And the funny thing is, that is from our previous interface, which was like, three plus years ago now. So we took some design elements from that interface that people really liked, and brought it into the advanced tab, so to speak, the Vance PCB specification tab.
So, okay, so there's a whole tab in here about vias. And you can basically select got a bunch of different options. Let's see, you made it through hole vias. Oh, and then you upload drill files, specifically for each type. Like if in your design files, you have a plugged one, you would have a whole layer of just plug vias and things correct, yeah, cool. And it also supports blind and buried there too. So
you can, if you upload a buried via drill file, you can say, hey, this is buried vias, and it goes from this layer to this layer. And it will actually draw has like a diagram there. And it actually will draw it out there too. So it actually will give you a cutaway of the vos.
Very cool. Then, on the impedance tab, you can upload impedance control data, instead of just saying yes, impedance control.
You can actually upload impedance control stuff and like, like an assembly doc or something you can upload there. Okay. Before it was like, yes, yeah, the
answer was yes or no, that's it.
This is really cool. It's cool to see it kind of like grow into having a bit more to be a little bit more in depth in there. And I look like I was saying I was, it seems really simple. But you know, sometimes it takes a long time to implement it, but having descriptions of things right on the page, like when I click extended drill, directly underneath it, it says, decrease minimum drill size to four mil like, I get what that means right there.
Yep. And the cool thing is, there's a lot of tooltips and stuff now too. I don't think that whole section is tool, tip doubt because it seriously came out today. And then like 15 minutes later, I launched like the basic documentation for it. Yeah. And so then Joey's got to go in take my documentation, making the tooltips all that good stuff. So
it looks like so the tooltips are based on some information bubbles that are next to the text. So some of the items have it but most of them down, but most of them don't necessarily need it
as true. So but
more ya know, the hey, that's great. That's awesome, man.
Thanks. So that went out today. Also got notification yesterday that the penetrator rev to PCBs arrived at the fab. And so I got a picture those those are pretty cool.
I'm curious. So you sent the picture off to me. And you went with clear solder mask on it?
Yeah, I've been doing my prototypes expected. Well, only if the prototypes are basically the, quote production class that we have at macro fab. Because there's just so many parts on them that they basically get bumped off the prototype class. And so then I can just pick the solder mask color for free, free in quotes, right? Yeah, of course. And so I picked clear I like to include for prototypes.
I'm a big fan of that also. Like make establish with your engineering team, a color that is a prototype and and never break that rule. I always like doing it that way.
I would just have done read it though that PCB fit into the prototype class that we have, I would have done that because it would have been less expensive. But yeah, I ordered for those and it just how many parts are on those boards? It bumped it out of that class. So nice. And also it was a six layer board. No, no, those are four layer. There's a four layer boards now. Yeah. So
you don't have a whole layer dedicated to 50 volts?
No, no, I wish they would be nice. Get in or that would be, but it's actually got like, because that whole area of that PCB is just for high voltage. So it's actually got multiple parallel traces in there that are via stitch together and stuff. That whole section. So yeah, there's actually I would say, yes, it's got a section of a plane dedicated 50 volts, multiple plates.
Right, but it's not like an entire layer with ginormous traces. Like you did
not like another one ground poor or 3.3 volt poor. Yeah, yeah. Cuz that boards got signal, 3.3 ground then signal again. And then in the fifth, the high voltage section, it's got one layer, it's got control, one's the return. And then there's 250 volt. Traces, or planes, I guess. Cool. So and that was done because the inner layers or the 50 volts. And inner layers have less heat capacity. Meaning that the same amount of current on an internal layer is going to heat it up more than an external trace on like, the bottom layer. So the bottom layer was like the ground returns for the solenoids. And those are they were, you know, spec that, whatever, I needed to be spec that. But on Enter, they had to be like twice as big. Because you had to dissipate all that heat still. And so I just made them the same width, but just made them double them up, basically. So I effectively made them twice as wide. Yeah, yeah. Yeah, that's what I did on the pintech. And it worked great. Never had any issues with those boards.
So you're gonna get those in two weeks or so.
They should be assembled by next podcast. Oh, okay. Cool. Yeah, that'd be cool. Cool to have them for the podcast, but it might not be for the podcast might be the week after that.
Okay. Are you actually going to throw these ones in machine? Or are these just going to be bench units,
they're going to go into machines like the last one. Cool. So we're going to put all the PTAs parts on them, ship them out. And I think the ones gonna be a bench unit pretty much because it's going to the person who's helping us do all the high level software for mission pinball framework. And then that would probably be benching in it. But I'm like, Yeah, make your own game with it. Throw in a machine abuse it, we need to break it before we go to production. For sure, yeah,
I'm assuming you're planning on going to production in 2020. Sometime,
right? Yeah, we're planning on that probably later in 20, June, ish. Okay. That's what we're aiming for. So we're well ahead of schedule on the prototypes, though. So as long as we don't have to have another spin unexpectedly. Let's see one more thing. This is the last one before production, we'll probably have one more minor rev, of just changing some of the connectors to be more specific. Like the example I give for that is like for the ball trough, it's like the same the ball child has like, it's the same unit and every pinball machine that we are working on, right. And so we wanted to have a dedicated connector for it, instead of having like, basically use four Opto connectors, because it's got four of those on it. And so using four Opto connectors just have one connector. That's all the same signals, basically. So you just reduce how much part count you have. And like your wiring harness and all that stuff. Make it easier for like, if you need to take the ball, trot out how to unplug for plugs, and then remember which ones they go back in.
Yeah, that sounds like a little or no annoying
other than the fact that prototype runs are expensive. I'm a big fan of doing multiple prototype runs, just because every time you do it, they always uncover something, you know?
Yes. Yeah. But it's actually given the fact that Rev. One worked great. We only have one green wire. And there I expect to have to down to have any real big issues. We'll see though. something bad could happen.
I mean, I didn't notice any significant changes though, right?
No, I didn't. I moved some stuff. for I don't know, but I didn't notice that I didn't change for one trace. So rev three is that's the first first issue I fixed already was. You already started rev three. Oh, course by saw that I'm like, dang it.
Yeah, yeah. Anytime you see a board with 90 degrees like it, I can't help but think that like, why didn't you spend the time to mitre um, you know, they just look nicer.
But the thing is, it's just it's it's one spot. Yeah. Of the board. I just overlooked when I was going through, because basically I'll draw everything 91st And then I go back and change for everything. Oh, do you really okay. That way because, well, Eagle, they added this thing. This is just be the case. And old eagle were like, it was really hard. If you move the part with chamfer edges, it couldn't keep the chain for edges. Remember that? We were talking about this dip trace kept keeps them? Yeah. So if you move apart, it will like kind of redraw the chamfer edges with you. It does a best guess. Yeah. So Eagle didn't do that. So if you moved apart, it would just make that chamfer weird angle now. And so I got into the habit of just drawing everything is 90s. Because then you could move stuff easier, because anything would keep the 90. And then chain for later, they added this thing called like, well, like do its best guess to do it. Yeah, but I always fucks up. So I'm like, you know my method? I just? I don't know, for some reason. It just works. That methods works for me now. So,
yeah, okay. It's somewhat of a tangent here. Do you have a, I guess? Sort of like a methodology? Or do you have a like a sequence of events that you do when making a PCB? Oh, yeah. Who doesn't?
I don't know. I mean, like, I've seen some people who don't like so what is your, what is your method? So we're talking like post schematic, right? Like, you've thrown the ball over the fence, like your schematic is done, you throw the ball over the fence and into layout? What are the list of things that you do to complete a layout?
So put all the parts that need to be in a certain spot first. Right, so like connectors, for the independence all depends on your what you're designing right? Your product, because like in a in a pedal, it's like, oh, the quarter inch Jacks have to be in certain spots, right to make it work.
Yeah, you're mechanically constrained items, you place those first,
there was a place first. And this case in the Pinball Controller, it was all the connectors in the place on the edge as best as possible. And then it needs mounting holes. And so the second thing I did was mounting holes, and to make sure I had enough space for the mounting holes, because it's not just a screw, you also need the tool needs to be able to get there. And you need to make sure that hey, if you had the screws there, or the screwdriver, and you let's say you tilted the screwdriver a little bit. Are you going to hit 50 volts, stuff like that. You got to think about Sure. Do that. That's step one. Step two is put parts. So use the ratlines and then or airlines depending on what your EDA tool calls them and put them I don't think Eagle calls them airlines. What does dip trace column ratlines? ratlines? Yeah, so I've always gotten ratlines, but then Eagle calls them airlines. So whatever.
I was so confused the other day when I when I was dealing with a customer's product and it was throwing warnings about I think they called them air stubs. Air stubs. Yeah, that's
another one that I was like,
What the hell is an air stub? Which is just like it's a trace within a pad. Kind of it's like an uncomplete trace that exist within a piece of copper that it won't hurt anything.
It just letting you know that hey, you can it's a warning. Yeah, just cleaning up your shit, man. That's what it's asking you to
do. Yeah, no, it really is. It's like, Come on, man. Come on. Yeah.
So put them put all the parts where they need to get like near the connectors. And that's your design contract. So in this case, like we use a lot of shift registers, and a lot of pull ups and pull downs. And so we, I basically took those parts and then like, Okay, this shift register needs these pull ups and this capacitor, bundled all those together. Next, all the connectors, all that stuff. And then I started laying out one, because all of them have kind of the same layout. So I had laid one out, and then of course, go back to the schematic and be like, Oh, if I routed it, or it's connected up this way, it makes the routing cleaner. Do that back and forth a couple of times. And then you finally settle on okay, that's the most optimal way to route something. Then route everything 90 And then this is what The four layer board. Okay, so we've got all those signals first as much as you can on one layer. Then, since I since I mostly do digital things, most time it's you plunge to the ground, then you plunge to your voltage. And then if you need the backplane, you got that for weird signals to have to like cross like the entire board for some reason. Because you always get a couple of those right? Yeah, that's typically the rundown. Kind of basic, but you know, I don't do some people will look at the pin, no, hit the pin help board, the pentatonic board and be like, oh, yeah, it's pretty complicated. Like, well, if you really break it down, it's not super complicated. It looks complicated when you look at it as a whole first, yeah, but you break down like the shift register section. It's like, oh, it's got pull ups for each line. It's got an inline series resistor for you know snubbing weird currents and ESD. And then it's control lines, rather than a cap. So it's like, okay, that times 20 is, like half the board. Right? Right. Yeah. And then like, the microcontrollers, just, you know, I've worked with the at Sandy 21 lot. And so I'm like, I already know that my schematic on that part works. So plop that down, around the same way with the crystal and the rights in the right spot. I'm always a big fan of when you're routing microcontrollers, is to, like, go to Dashi and count how many VCC and Ground pins doesn't have on on its pin outs, right? And if the VCC and Ground pin are next to each other, that's like a you call that like a unit a power unit? Where there's one bypass cap for it. Yeah, so you have one bypass cap for that unit, right? So that's it, the pins are next to each other, if they're separated out, then I tend to go, Okay, if they're more than, like four or five pins away from each other, they get their own bypass caps, because they're far enough away, where you do start to get some impedance in there on the on the lines. And so yeah, so like, I think the atcm DS got like, six, or six or seven bypass caps on it, which a lot of people would be like, that's way overkill. Like, yeah, it's overkill. But guess what? It works the first time every single time.
Yeah, I mean, I've been putting bypass cap, anytime anytime there's a power pin, it gets a bypass cap. It's and I consider it lucky if there's a ground pin next to it, because then you can put the cap, because I use Oh, 402.
Did I went oh six or three on this one. Okay. But if you're Oh, four or two you can get
you can squeeze them right up on there. And it's that's the best. And actually, yeah,
that is better. The small, that's the thing people will think about is the smaller part allows you to shove it closer to the pins. And so you have you even have less inductance and impedance on that. That network, so to speak that power network. Right, right. That's why you'd like if you have a really fancy BGA and you turn it over, and it's got like 80 bazillion bypass
caps. Yeah. Yeah, it's got acne on the back of the board.
Yeah, yeah. Look at the back of like a graphics of graphics card or something. Oh, those are insane. Yeah, it's got tons of them. Yeah. I always err on the side of more bypass caps, the better in terms of that and making sure they're close as possible to the pins. Like I've been having on like, the shift registers and stuff even though technically, they probably don't need them. Because we you drive them so slow, but it's okay. You know, in the overall scheme of things per unit, it's like five cents. So and this is not a super price conscious board, where like we're building millions of these things. So that one capacitor, it's like that all of an American Airlines and their salads, right? But they removed one olive and they saved like 8 billion or $8 million, or something like that, like the dollars were the 8 million or $8 million olives, something like that. It's like that's ridiculous. This is how many people eat salads on airplanes, which boggles my mind. Yeah. But yeah, so if you're not like, being counting that low, yeah. Then yeah, just use as many as you want. Need.
Right? Yeah, one per power. Yeah. I wonder
if there's like a limit to that though. Like, what if you Oh, we could write a script to do this. And Eagle. What if you made it so that like, you laid out your whole board right. And then you press the button, and it populated? Oh, four 2.1 micro farad caps, anywhere it could on the backside to
I mean, the limit would be what your power supply can handle in terms of capacitive loading.
Yeah, right when it turns on Yeah, search? Yeah, it would be disgusting search
they coat okay, you should, you should do that the smoothest board ever. You know, one of the things I've started doing, especially because a lot of the boards that I design now all fit within like a certain scheme. They like there's like a known size PCB. Before I even start the project, you have an enclosure that you're designing to, right? Yeah, well, and the enclosure is, is it has thick, like, yeah, it gets wider, but it but gets wider by fixed widths. So like, I know, it's going to be, you know, one and a half inches or something. So the, what I've started doing recently is the the first two things that I do, the mechanical items are almost always predetermined before I even get to the PCB, because we draw like artwork. So we know where like knobs and things are gonna go. So I don't even start with a mechanical stuff, I start with the board outline, I start with my mouse baits. And I start by placing my fiducials on the board, those three items I placed there, and then I set up my clearances around all of those items, such that before I even begin placing anything down, I already have my don't place around here areas,
it sounds like at that point, you have like 50% of the board you can play with.
I mean, it is somewhat restrictive. But what's nice about that is like I've had a couple of boards where I laid the entire board out and it was gorgeous. And then I didn't have kids and mouse bites. And I put those in and I was violating crap, you know, so then I had to go back and fix it. And I was like, why don't I just start with those because I will always generally know where my mouse bites. And I for sure know where my kids are going to go. So I put those down. And it's funny, because if you start with the constraint of I'm not going to place in these areas, then like it's never even an option in your mind. And you just get it right the first time.
Yeah. And that in that same regard is mounting holes go in that as well. That's what I yeah, that's Oh, yeah, for sure. Mounting, making sure you have mounting holes. Yeah, where you need them to go. Because this one, it's like, okay, each big connector needs a mounting hole next to him, because someone's gonna be yanking on this, like this connector in the dark. And you don't want to rip the board out. I guess I want to could done better is I could have put keep outs around the connectors for bypass caps. I just did that just because I know not to put a bypass or a capacitor a ceramic capacitor next to a connector or mounting hole. But um, yeah, that can be something that you could add in.
Yeah. Something that I think is really important to kind of keep in mind. And it's a lot of people might roll their eyes at this because it's a little bit obvious, but it's not always obvious. Keep in mind, like if you're doing mounting holes, like try to have a good understanding of what the hardware is going to be that goes through that hole beforehand. Research, like clearances for whatever mounting hardware is going to go through there. And then know beforehand what head of the hardware is going to go through there and make your clearances and keep outs appropriate for the head goes. I mean, I don't know if you've ever done it. But I've made the mistake before of like not researching the right size of a pan head screw and having something too close to the pan head screw that went through the hole. I got the hole right, but I didn't put clearances for the for the screw.
I haven't had a problem with the head. I've had a problem with tools. Yeah, sure. Is I on the first production pin heck board, which is like rev four. Pin hex. This is like seven years ago at this point. Yeah. One of the screws was to close their connector. And we used hex, like computer screws, so they had Phillips with the hex code on it. And that one was the only one you had to have a Phillips for. Because the socket didn't fit over, because the connector is too close. But when we fix that next rev and then everything was hunky dory. Yeah. So that's one thing like I have a I have a footprint for that connector for that mounting hole. That is this is the screw we use with this head. And this is the diameter of the tool. The tool clearance is like half an inch, which is ginormous, huge. I mean, someone's poking at it with a screwdriver in the dark. You know, the worst thing that can happen is they miss with the tool and it goes into 50 volts or it goes into a bypass cap or it goes into a chip and flicks the chip off. Yeah, like that's, yeah, a lot of people commit grand PCB, like failure. Failure. Yeah. Well, I didn't want to use failure. I couldn't come up with a word for that, you know,
I made a mistake earlier this year on a board. Luckily, it wasn't a big mistake. But there's, there was a board that had three different styles of power connection headers that go on. And they're like one was a ribbon one was like flying cables to a header and then a third Molex style. And I put all three of these on the edge of the board. And I gave them space in between each other. But I didn't. Like there was plenty of space between the male connector, but I didn't, didn't fully pay attention to the female connector. And the female connector was a lot wider for each one of these than the male connector. So it was impossible to have all of these cables connected at the same time. Now, technically, for this circuit, you should never have more than one installed at the same time. Like, the reason why you would ever do that is to daisy chain power from one circuit board to another. But that's sort of a no, no, there's just some, like really rare cases where some people want to do that. So it wasn't an issue because it was one of those things where it's like, Well, you shouldn't do that anyway. But you know, something I had to fix. And it was just like, I have on my board. Like, I didn't have any DRC errors, because my connectors aren't touching, but I didn't think about the connector that mates with it. And that was bigger. Just like God dammit. You make mistakes. You move on.
Yep. Or have to. Yeah, that's the problem with those mistakes is they're kinda impossible to fix. It's not like, Oh, you forget a trace, or something's wired up on you can cut some traces. Do some soldering. This is like, Well, shit. That's that's a rep to thing. Yeah, it's
a revenue thing. As as AVI would say, there's always enough time to fix it in red to.
Too bad. We can't fix it and post.
Yeah, that's for sure. Yeah. This is why this is why double e's are kind of anal about, like their board designs and stuff. You know,
is this why we can't trust people with our footprints? No.
Yeah, you cannot trust? Yeah, for sure. Like, if you pull up some random person's footprint, and you see an outline, do you trust that outline to actually be the outline of the part? Yep. Yeah, I shouldn't have even trusted mine
is probably why every single hardware engineer, we've talked about this for every single hardware engineer has like their own, like, this is my library.
Is my sacred library. Perfect. It's like the tufts. Yeah. Cool. So
So what are you been working on?
Similar to you, actually, you kind of jumped on to the pin guitar riff, too. I kind of moved on to doing what what I call the hellhound preamp. This is actually a project that that Roz, who was on the Star Wars Episode. And he's been a guest before. He and I've been working on this for months and months.
Like a good chunk of 2019. We were doing development in a sort of culminated with the goal that we'd have it done by the end of the year. So I sort of rushed and jumped over to this just because like I wanted to meet our goals.
But luckily, like my brewery,
Hey, is that done? You have a few hours.
So it's getting there. It's
it's getting there. I like that. That's great. Actually pretty close. Yeah. Okay. So Parker has been sending me images for the past few weeks of of stuff. He's making lots of progress. This is not one of those ones, where it's like just in in theory, he is making a lot of progress. So yeah, so the hellhound was a it's a two preamp that I that I've been working on. But I did everything all on a single PCB with a right angle, Billboard style, PCB to fit within a rackmount unit. The prototype, the initial prototype for it was talked about back in episode 199. And I got boards since then, that include the power supply because that that first prototype, I was just running off of a benchtop power supply. And I did, I did sort of a dual transformer back to back design, that was a step down to the low voltage for the heaters, and then using that to step up to the high voltage stuff. And what I'm super excited about is it actually works really, really well. And the transformers are in generally, they're in close proximity to a lot of pretty sensitive audio stuff. So I was kind of worried about coupling and things like that, and I've got virtually zero coupling on it. So I was I was kind of like sweating it there because I'm just like, I don't know if this you'd like a lot of that stuff. You kind of have to just like do best practice and then build it and find out you know, and so that worked out really well. I didn't make
stop people quick. I think I remember back in 199 You were talking about that dude Little transformer setup. Yeah. And the only downside to that really is like, it's inefficient, right?
It's yeah, it's very inefficient, but it's cheap and it gets the job done. And because I'm not, I'm not trying to sell this, this is more of a prototyping platform. I just wanted a power supply that I can plug into mains, and be able to ship it to Roz up in Connecticut and just have him be able to play with it, because he doesn't have a high voltage power supply on his bench. So yeah, it was mainly for inefficient. I mean, cheap, but yet inefficient. And the thing is the so what I'm doing is I'm taking one transformer, where it's a step down transformer, and then I'm reversing another transformer. So I'm taking the secondaries of one and plugging that into the secondaries of another and then boosting that up. So I'm using the primaries of another transformer as its output. And one of the things that kind of sucks about that is the especially for these flat pack transformers that I got there, triad transformers that you can find on Mauser, the, the secondaries are regulated pretty well, whereas the primaries are not regulated well. So if you reverse a transformer, and put voltage as an input into its secondaries, and the primary is not regulated, then you sort of not going to get what you're looking for. And that's what I found out. But I was, you know, I was trying to shoot the side of a building with a shotgun on this kind of thing, I just needed high voltage, I didn't really even care what it was. Because on my initial prototype, I played with it, and I swept the voltage from 250 to 400 volts. And there was virtually no difference between that entire range. So as long as I hit anywhere in that range, I was good. And I totally hit within that range. So but the thing is, I did use like a calculator, and I did simulate the power supply. And I'm like 50 volts off of what I thought I was going to be on. And mainly mainly, that's due to the fact that the primaries on these transformers are not regulated the same way that the secondaries are, so whatever, it still works, that's all I care about. I made a mistake. However, like, maybe mistakes, not the right word I just didn't, I didn't fully account for the ripple that was going to be on it. So I did. Right after the rectifier, I had about 200 millivolts. Now, not even probably about 150 millivolts of ripple, which isn't that much. But it was coupled through a buffer directly to the output. So the output has a low level 120 hertz hum. And like I looked at the ripple on my scope, and it's not like a dirty hash. It's not like real choppy, it's a smooth ripple. So it's, it's clearly capacitor charging stuff. So the good thing is pretty, I actually have two capacitors in parallel, right on that, that output, so I was able to cut the trace in between them, and then build a Gyrator circuit in between those two caps. And just basically simulate like a, I don't know, like a 50 Henry choke in between, like, It's a monster choke, and it just obliterated the noise. So super easy. And that's sort of what the whole idea of these prototype things are. For which, so we talked about generators back in episode 173. And something like that, when it when it comes down to dealing with these kinds of circuits, if you have a bunch of extra voltage to play with, which I do, and you don't mind getting rid of a few volts here and there, like Jai readers are actually really, really convenient. And they only take a few components. And in terms of like, connecting a Gyrator and a capacitor together, you get an LC circuit, which you can tune to have phenomenal filtering. So you know, keep that in mind. Research generators, they're super useful for this kind of stuff.
Might be pretty good through bike design a, a, a Gyrator circuit, that's kind of like a general purpose one. Yeah, like and making a PCB. Yeah. And then that way you can like you can populate what parts you need for what values right? And then you can just kind of like graph that onto whatever project you're working on. Yeah, yeah, that's
a great idea. The generators will be a simulating, you know, I actually have a customer that I'm doing a design for right now. And they have they have a power supply that has an inductor in it and the inductor is kind of an annoying value. And I was considering putting a a Gyrator in there. Especially because if you tune it, the impedance of the the Gyrator simulating the choke and the following capacitor, if you tune it just right, you can get like massive amounts of reduction of ripple right there. But the thing is like at It's probably not even necessary because these, these projects are being powered off of an already cleaned supply. So it's just I don't know, it's way overkill. I think it makes a lot of sense directly after a rectifier, especially in these kinds of applications that I did with this hellhound preamp. So
that yeah, that was that was fun having to hunt down noise because at first when I when I first fired everything up, and I turned it on, I thought it was coupling from the transformers. And I'm like, Oh, well, that means we have to, you know, like, there's nothing you can do this. I was I was going through my head was like, Okay, how do I make a tinfoil hat and grounded around my Transformers and try to get rid of, you know, whatever II field is flowing around? No, no, it just ended up in power supply noise, which now that I look back at, it was like, wow, I put way too low of a capacitor on the right after the rectifier, it's plenty big enough, in general, but for this application, it it could have been bigger. And you know, so the thing is like, also, if you have noise, just making whatever your reservoir capacitor after your rectifier making that bigger, isn't necessarily like that doesn't solve a lot of issues. Because you'd be surprised at how big you have to make it to get rid of noise. So coming up with a more active solution can actually be a lot cheaper and smaller and a lot easier. So yeah, checkout Gyrator. So pretty cool. So one of the other things that I installed in this and I talked about it in some previous episodes was a a four band EQ that began its life purely as a SPICE simulation. And that will that EQ actually includes a couple of generators also to to actually isolate all the bands in there. But the cool thing was, I actually pulled up the SPICE simulations, reran all the all of the plots, and then I put this preamp on my scope. And I set the scope such that so there's 10 divisions of width across my scope. So I put a sine wave into it. And I swept the sine wave from 10 Hertz to 10 kilohertz. And I swept that in one second. And then I set the divisions on my scope to be equal to a 10th of a division, or a 10th of a second per division, such that every time it swept across the screen, one screen swipe would be 10 Hertz to 10 kilohertz. And then I could adjust the EQ controls and look at the amplitudes. And the amplitudes would basically follow the frequency response of my simulations. And what was cool is it was exactly on like my SPICE simulations and the in reality, were one to one, they looked almost identical. So super happy about that.
You know, Spy simulations in reality should be a short, sci fi like, story,
with the eyes glowing and stuff,
matching the simulations.
I picked up a book for Christmas that you know how to read. Yeah, no, it's surprising. I picked up a book about SPICE simulation for LT spice over over Christmas. And I've been playing around with LT spice, just because what I've noticed is I use P spice mainly for my stuff, but I don't have a full copy of it. And it's kind of janky and the way I've been using it, and a lot of people really speak kindly of LT spice. And every time I've used it, I've kind of felt like, not really sure about it. But I was like, You know what, I'm gonna get this book and I'm gonna start working through examples. And now that I've been playing with it, I actually really like it. There's a there's a lot of, I don't know, there's a lot of annoying things about it that PSPACE does that I wish LT spice would like, if you if you plot a anything in P spice, you can select the wave. And then you you're allowed to do mathematical functions on it, which you can do in LT spice, but you don't get all of the nice ones that P spice does like if you want to find the RMS or the like I guess the traveling RMS of a wave, you just RMS and then parentheses, whatever you want. And then it just you plot the RMS. But in in LT spice like you don't get those higher level functions. You can do just things like add and subtract and multiply and things. So you could do an RMS but you'd have to kind of calculate it yourself. And they have they have a handful of other. I mean, they have ways for you to look at RMS we like you can Control click on a line and it brings up like a little command box. It says here's the RMS of this wave, but it only it But it calculates the RMS of what you're looking at. So if you're zoomed in, you get a different RMS value of if you're zoomed out. Or if you're trying to find the RMS of like a rectifier circuit that has charging, then it's strange. Like you want to look at RMS based off of time. Piece by piece does that really well. lt spice doesn't seem to do that. Well, I'm not. But then again, I'm still somewhat new to it. Chapter
yeah. The biggest thing I think that threw me off with LT spice is the user interface is a little clunky. And when I say little, I mean a lot clunky. It just it. It's like, why should they? Why should a simulation or space program run like a drafting program? And it feels like LP space runs like a drafting program, where it has the whole thing where you have to like, I'm selecting move, I'm selecting my item. I'm septic, like, why it's a splice simulation. Like just let me throw it on a resistor and like connect wires, but whatever I can I can get past that. It's just a matter of using it. It just doesn't make any sense to me why it would not be that Yeah.
Even Eagles not that drafting. Like, yeah, I know what you're talking about, like AutoCAD. When I learned, AutoCAD 2000 is like that. Like, like, I'm going to do this to this. And yes, I want to
do that. Yeah, well, and fusion 360s Kind of like that. And I really liked the way fusion 360 handles like, if I'm in draft mode, that all makes sense. But with with LT spice, it just, I don't know, like, there's certain things about it that are kind of janky in that sense. And like the quick commands are all weird. Like, why is F seven wire? Why isn't W wire like F seven is a weird thing that my hand isn't used to being on I play games. So ws A D, like those should be the hottest keys out there for like working on something you know. And in Peace Prize, W is wire, it's just like you clicked w? And like, Okay, you're drawing a schematic, what is the one thing that all schematics have, and you're gonna be doing a lot of, you're gonna be wiring, right? Like, have wire be the easiest thing to get to. And it feels like LT spice, you have to like, click the wire button, and then click the one thing you want to wire to the other thing, it just feels really slow and clunky because of that. But then again, you know, it's not like they're making circuit simulation for the masses, and they have to, like fine tune that stuff. They're gonna they're making free also, right? Yeah, yeah, it's free. But ya know, so far, I really like it. And I think I'm going to start migrating over to it for all of my stuff. And as I go through this book, I want to start looking into sharing some more things I learned about SPICE simulation, because what I'm excited this book goes into nonlinear circuits. And later on, it starts talking about nonlinear current drawn circuits and distortion effects on your, on your signals based off of that, and how to simulate and identify those. But it also goes into full system design, where you're looking at your power supply draw, and you're simulating the effects of that and transients, based off of hiddenness Yeah, it's kind of cool. It's good stuff. So
I'm sending something I can use. Yeah, yeah. Because I don't, you know, I rarely seem like anything, because there's a different world of designing stuff. Right. Right. And but I'm like, well, one thing I like to make sure is my power supply stuff is designed right. And we were talking about earlier, like the bad stuff design I'd made like I designed a PCB just testing that stuff. Yeah. But it'd be nice to be able to simulate it besides going oh, yeah, I'm gonna plunk down 100 bucks and hopefully in two weeks it works right.
Yeah, well, simulation can help prove that, you know, and I love when when the circuit you do, you actually great follows the SPICE simulation. And, like, don't don't take this as like being me being super arrogant, but it always feels somewhat parallel. What was it? Was it Neptune or Uranus? I can't remember one of those planets was discovered mathematically. It was one of the first like major scientific discoveries that was based not on observation, it was based on math, like we observed other planets, the way they move, and they had very odd movements at some portion in their travel in their orbits, and the only thing that could explain them having those is the presence of another celestial body. And so they calculated that the planet existed before observing it and then when I and pointing their telescopes and actually observed it. And I feel that SPICE simulation is kind of that way where it's like, you have an idea in your head, you do the calculations, you run your simulations, you get your plots, then you actually make the thing and it always feels like I discovered a planet you know, even if like your one little filter works out.
So I was I Wikipedia, your anus? I'm sure you did. But my my thing about it is exploration. See if I can find out if I don't think it was your anus because I don't talk about there. But it's just the line says in 1986 NASA's Voyager two interplanetary probe, I encountered your anus. I'm like, encountered, you know, I knew it was going there. So is it to me encountered means like it was an unexpected event that happened? Yeah. So that's, I think that's the wrong word to use there. Oh, she's wrong. I just think encountered is something that's a unexpected kind of event of you meeting something. Someone's gonna be like, actually.
Yeah, so it was Neptune. In fact, there's an entire Wikipedia page called discovery of Neptune in the first sentence was the planet of Neptune, which was mathematically predicted before it was directly observed.
There's also another planet that they're trying to find. That is, same thing. It's past Pluto. It's an echo, which is not a planet, it's an exoplanet that's somewhere out there. And they just don't know where to look for it yet. But they definitely do observe some kind of gravitational pull out there. And so they're looking for it. I think it's like called Planet Planet X. You can call it planet X, because it would be the 10th planet.
discovered the year 2009
was Planet Nine, right? What was it? Was Pluto was Yeah, Pluto was Planet Nine. But not It's not Planet Nine anymore. So you can't call it planet X. Right? Well, it'd be Planet Nine.
And it's, you know, the reason why they made it not nine made it not a planet. And sorry, you can't like necessarily make it not a planet. There was a council that got together that discussed, like, what are the requirements for a body to be considered a planet and Pluto ended up meeting two of the three requirements. Yeah, and one of the reasons why it would be confusing if Pluto was a planet, is there's a lot of other bodies that could be called planets. And we, the universe where or our galaxy, our solar system, I should say, would have a lot more planets in it if we allow Pluto to be a planet. You know, so I don't know, I support that. I think it makes sense. I think what it was was one of the rules that it didn't pass. Oh, I think one of them is it has to be spherical. So that means it has to be a body greater than 500 miles in diameter. I think the one of the other ones, I think it has to orbit the sun. And then the third one is that it has to clear its entire path, like its path can't have anything in the way and that's the one that it hasn't completed yet.
Because there's a lot of objects that are really close to its size, right that are in that orbits.
That's right, yeah, all the other planets have cleared their orbits of other space stuff.
We'll get you one time moon.
Cool. So there's actually one other thing I wanted to talk about on hellhound preamp that I got. So I ended up going with a $10 switch that's in it. And normally I wouldn't put anything at all that expensive. But I found Okay, so I found a family of switches that all like fit the bill that I wanted. And they're all really expensive, but they're really nice, like three position toggle switches. So you can have like different tonal options and things with them. So is
it got a up mid? Down? Yeah, yeah, it's
a three position and it's an on on on switch. Okay, yeah, so it's a four p d t, three position, which is super unique. So it's two DPD teas that if you connect two of the pins together, then you can have each DPDT has one input and three outputs. Like that's a really really specific switch like
was like when I was getting the switches for the wagon. Yeah. And like, yeah, those you were complaining about $10 switch. These were like $24 a pop. But they had to have very specific you know how they connected up when you because it was like Got three position is a no four, four position three pole, very similar style switch. Yeah, but like I needed to be like I had to have a family, because I had to have all the switches had to look the same, right, so I had a different requirement. And I had like four different switch styles, and they all had to match.
Yeah, cuz I have I have four switches in this thing, not four of the $10 ones, I only have one of the $10 ones, but I have four switches in them. And luckily, I was able to get all the switches with all the same battens with all the same like skirts on them. They all sit off the PCB by exactly the same amount. The only thing that sucks is one of them had to be $10 Because of that, but the thing about this switch that makes it really, really nice is it switches three different modes. And those modes in either engage or disengage different Zener diodes that clip the signal. So if you're clipping the signal, then your total amplitude drops significantly. So I have one half of this switch that switches in different diodes. And then the other half of the switch switches in different resistors that are in series with my potentiometer. That is my master volume. So as I flip the switches, I can keep the volumes relatively the same even though the amplitude is actually dropping due to the clipping. I can flip in things such that you don't get like huge pops that go through the signal. Yeah,
or that or if you switch from one to the other, you're basically your output is the same no matter what your clipping. Exactly. And
it's not perfect because it's based on previous settings earlier on. It's just with this switch, I can make it a lot less drastic, because my highest level of clipping is 3.9 volts. And my smallest level of clipping, which is no clipping could be up to like 40 volts. So think of like a 10x amplitude increase from flipping a switch like you could you could cause damage to the circuitry later on. So I wanted to make sure that when you flipped a mode, it would automatically readjust itself. And really the only way I can think about think of doing that with high voltage capabilities is to buy a $10 switch. So it's like ah, that sucks. So if anyone wants to check out the switch, it is 1004 P six t one before and seven. Our e
would not be a macro epigenetic podcast episode without a long part number.
Check it out.
That's always my one of my favorite parts of this podcast.
Yeah, that we just like, these were decreased part numbers. Actually, you know what's funny is I've looked at these switches so many times that I could break down that that and tell you what leaves me and sisters. Yeah, I could tell you what, like er Jays? Yeah, yeah, the T one. Yeah, I know the RA at the end is gold plated pins.
We shouldn't do a podcast, we should do a future podcast on like, we should pick a series of like what we use a lot and do a breakdown of the part numbers.
Oh, that'd be fun. And like,
that's the this is the like the only podcast that people will be like, Yeah, I want that. We're gonna talk about data sheets for a whole episode.
We've done a lot of that. And I'm, there's more to talk about. That's for sure.
All right, so man, we're almost at an hour. So let's go ahead and run to the RFO. Yeah, Leon sees rip to the orifice. Okay, so this being the last episode of 2019, y'all will hear it in the new year and 2020. We're gonna go do a quick overview over like our personal favorite podcasts episodes of 2019. So I'll start with mine. Mine favorite was the discrete atomic glue for control, which is actually the first episode of the year, where we had Ben and Chris on to talk about 3d printers and loofahs, which was probably one of the craziest podcasts we've ever talked about. Like this. The topics were so very, we talked about like, a 3d printer that can print a whole room and then like genetically modifying loofahs to like make watermelons and organs. That's like human organs.
Yeah. That was That was crazy. And you know what's nuts? That was recorded in the bomb shelter in Houston. And just to think that that was only a year ago. A lot has happened in this this year.
Yes. Yeah. Was that recorded in the bomb shelter? Yeah.
Because Ben Heck and Chris Craft. I remember sitting on the couches in the in the bomb shelter.
Hmm. Was that this year because that bomb shelter went away in Harvey. That must not have been this year. Why does this podcast say January 2 2019. Then it must
have gotten uploaded at the wrong time. cuz we've recorded that and it doesn't make any sense. Yeah, we recorded that shit in a bomb shelter do because that's when you and that's when you guys came. They flew down to go fishing and you guys went on your B 17.
That was that was like two years ago. No. I swear, Rex, you are here in Houston.
Yeah. And I was here in Houston in January that No I wasn't.
Yeah, a year, because it was in the summer. No, you're totally right. Why is this podcast I uploaded? 2019.
Did we didn't know we didn't know we did this one in person.
Yeah, we just in person. Yeah. Well, it's not that. Clearly the blog is incorrect. Yeah, I'm also looking. I'm like, What is going on with the blog?
Well, if this is Episode 153, then that would be a year ago.
Yeah, because it said, Yeah, I'm looking at our schedule and 153 was then what? No, we did another episode then. With them.
Does simulation match the reality episode 75. That might have been
episode 151 53 was Ben Heck and Chris Craft. Yeah,
but episode 75 was also Ben and Chris Craft. That might have been the one I was thinking of.
Which 175? Yeah, you're thinking that one. That one was the one when we were in the bomb shelter.
That's July of 2017. Which is a month before the bomb shelter got rained out
flooded? Yes. Okay. We're not super crazy. No, just me. No, I thought we were I'm like, wait, we didn't record this one in the bomb shelter. But I could swear. I can imagine in my mind looking at Chris Craft talking about loofahs I
swear. Like, I swear we were in there. Like I could see it in my head. Right? Yeah, no, exactly.
It's memories. Weird.
It's really weird. Yeah.
Dang, that was only like, that was only a year ago when you already forgot where we recorded it. Oh, yeah. Yeah, we had to recap because here's pastor years. Both were last seen on episode 75. Does the simulation match reality? That's
the one that was in the that's the one where you went fishing with them down in Galveston and they came to the bombshell. Yep, yep. Yep.
Yep. Well, in this case, the simulation did not match real reality.
Hey, speaking of bomb shelter, recording. One one or a pair of guests we had on that we should get on again is the idea. Tank. Oh man where they were fun. That one was really really fun.
That was a it was something was Xenos uh, yeah,
they brought they brought. They brought six. Zebras. Yeah, they're I think it's because I lost a bet. And they they paid my my
pager fee. They paid my fee was.
And we took a picture. We took a picture under the ET photo, or the eating picture that was up there. Yeah.
I wonder if that survived the flood. It probably did. It was more than six feet off. That was a that was a piece of artwork. It was gorgeous. Yeah,
it was like a fully like crocheted or knitted et or something. freaking great.
It was amazingly bad. It's so good. They haven't had a Twitter update since October 2018. So I had to reach out to them and see if they want to be on the podcast. Yeah,
I was that one was really, really fun. So So one of the other ones from this year that I think I picked for one of the favorite podcasts was the ken and Chip Gracey of parallax, which was episode 166. So a few weeks after the Ben and Chris one, where we talked about the prop two chip, and really semiconductor design as a whole. And I just thought that one was super interesting and really fun.
Yeah. Chip and Ken are super passionate about that industry.
Yeah. Go listen to the episode and you'll see why. Yeah,
I just wish we had better audio for that. Because like chip was like, eating his microphone.
Yeah, he was he was into it.
Because we because he was so excited to talk about this. Yeah. That always saw because he was had a talk with his webcam mic on his laptop to do that one. Yeah. And so and he had to get really close. Because if he tried to increase the game too much, we got too much room noise. So he had the gained way down. So all we could see was the lower part of his nose and his chin and mouth. Because he had up on his laptop like lid. Yeah, it was. It was awkward. It was really fun. And he talked a lot. Yeah, but it was like it was all super great.
That was amazing. Yeah, that was that was a really fun one.
And then you have an honorable mention.
I do have an honorable mention because I think This one has had some sticking power Episode 194, which was just a few weeks ago, or two months ago or whatever. And that was called the fourth rule of robotics. And one of the reasons why I really liked this is because in the episode we described, the fourth rule of robotics is that all robots should have googly eyes on them. And ever since we have released that episode, whenever we post things in our Slack channel, we get called out anytime we have not photoshopped googly eyes. The item I don't think it's 194 it wasn't one only four. I thought I grabbed that from earlier.
194 was Jerry.
Okay, maybe I got the wrong number. It was not that long ago. No. Oh, 192. Sorry, not 194
Sin further go. Yeah, bye. Ah, yes. That was actually also the episode that you made the that was the first time you ever made a featured image for the podcast? Episodes.
I've made a lot of the things that are in the the notes. Yes. Yeah. In the image, too. I just have an image.
Yeah, yeah. But like you I'm like, Siemens, like I got a great idea. I'm like, give it to me in 900 by 400 pixels.
It's gorgeous. It's absolutely amazing. Yeah. So thanks for everyone for calling us out on the Slack channel for not putting googly eyes on anything we post on there. Yep.
I like the fact that what episode My honorable mention would be is recent. It was not integrated. Low foul, right. No, it was it was the not letting not and was it not enjoying a loaf? No. There's like two Oh,
yeah. It's a really great non loaf.
Not into the meatloaf. Yeah. Because I got to actually use a picture of the album cover, right? And I'm like, Yep, I'm gonna Photoshop a PCB on that and chip it.
Oh, you know what? I don't see any googly eyes on it, dude.
Actually, someone called me out and said,
Of course. Yep. We continuously violate the fourth law.
Yes, all the time. Well, I don't know for motorcycles of robot
that motorcycle has like a dead horse's head on it. It totally beats Google's googly eyes.
Have you ever looked at that picture and see how the guys riding that motorcycle? Yeah,
it looks really uncomfortable. Yeah.
He's writing it with just his groin. That's what he's doing.
Okay, so we would like to call out the list of guests that we had in 2019. And give a thank you to everyone who's come on. So, Parker, why don't why don't we take turns go one than the other. I'll go ahead.
I get the easy ones to pronounce.
Like and he's rearranging them. All right. Okay, well, then why don't you start off because that's an easy one.
Okay, so thank you, Ben. Heck for being on the podcast. And thank you, Chris Craft. Thank you cliff. shipped.
I think it's checked. Checked. Thank you, Jason. Surrender Low.
Thank you. Al Williams.
Thank you, Chris. Row Howell.
Thank you, Phil. bris Han Bresnahan Bresnahan. So you get to pronounce them all the very beginning of the podcast. So you used to have these in your memory bank somewhere. Yeah. I like it. I like how you
call it a memory bank. Yeah. Thank you, Dylan Nichols.
Thank you, Ken. And Chip Gracie.
Thank you, Kevin Beller Thank you, Danny Rancic. Hey, thanks, Roz.
Thanks for us. Thank you, Nicholas. Peter. Show off pub Celio POV Chela POV thanks for all the hard work. I did the order wrong.
This is great. Thank you. Chrissy Meyer.
Thank you. Greg Paulson.
Thank you. Sruthi Surah Thank you, Jared Hayes. Thanks, zap. Hi, Ron and the and not XR team. Thank you, Joe Grande. Thanks, Mike Guyer.
Thank you, Jeff. garoun. Thank you, Daniel. Hinds itch. And thank you, David. Goodness. Yeah,
we totally screwed up gunness in the show notes beforehand. And he and he called us out because I because I actually spilled a Guinness and you
know, you got beer in the brain.
Thank you so much for coming on and making 2019 a fantastic year.
Yes. And so as we close out 2019 Let's make 2020 the best year ever for the macro engineering podcast even. Yep. So thank you all to our listeners, our guests have a wonderful New Year's everyone and let's make 2020 Awesome we'll see you in 2020 Yes You know what? Let's have a normal altro later everyone take it easy Thank you. Yes you our listeners and guests for downloading and being on our show. If you have a cool idea, project or topic, let Stephen I know. Tweet us at Mac fab at Longhorn engineer or at analog EMG or email us at podcast at Mac fab.com Also check out our Slack channel. If you're not subscribed to the podcast yet, check that that click that subscribe button. I guess you can check it out too. But yeah, click it. Hit that bell. That way you get the latest episode right when it releases and please review us wherever you listen as it helps the show stay visible and helps new listeners find us
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