On this episode, there are some AND!XOR hints for DC29 and we discuss the difference between PCB DRC specifications for clearance and creepage.
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.
Visit our Public Slack Channel and join the conversation in between episodes!
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!
Hello welcome to the Mac fab engineering podcast. We are your hosts Parker Dolan
and Steven Gregg.
This is episode 173.
So Parker, you've been? You've been working on your shitty add on, right?
Yeah. So last year we made a map should he add on which was like the the map, the macro engineer podcast logo, which was like the Mac Feb logo with a hamburger, right? Yeah, the hamburger and hotdogs, right? And, and it had a bunch of LEDs that lit up and stuff when we use a EFM. Eight, for recall to to run all the LEDs. And so bugout how long ago? Was it like six months ago? What better idea for this? Should he add on?
Oh, for this one? Actually, let's let's take a step back. It's probably worth mentioning, like explaining what a shitty add on is.
Yes. So should he add on is a PCB that goes on to one of these conference badges, like at DEF CON. And so it's got bunch of circuits on it. And usually, they are just like pop culture PCBs with just two LEDs on it. Right? And so like, and they just light up? Well, I mean, we're engineers, we can do better than that. Yeah, that's right. It just might take six months. Yeah, just might take six months to start it right.
Well, but you started it and got really damn far on it.
Yes. So about six months ago, Steve and I were coming up with some like, stupid ideas while playing a video game.
And too much beer was involved.
A little Sure. And so we were like, oh, it'd be really cool to have a doom should he add on? And so we went down this whole rabbit hole of like, what it could be and what you do, and I actually really liked one idea that you had, which was like, make a doom guy like face badge
yet, like Doom the video game from or the computer game from? What? Early 90s? What 92. So like, in the game, like as you're walking around the first person shooter at the bottom, where there was Doom guys face, and that was sort of like your indicator of your health was how how bloody his face was. But like it just this guy's face that like, looks around left and right and smirks every once in a while?
Yeah. And so we had this idea for like a big batch. That would be his face. And then like the eyeballs could move and stuff like that. So you could see his facial expressions that way. Yeah. And we never really got around to doing that big batch. But I'm like, I took that idea. And made a shitty add on version by using a little tiny screen. And to drive all this because there's a lot of like, like driving a screen you can't just do with like, you know, just you can't just power the screen and expect Doom guy to show up. Right? Yeah, there's
a little bit more to it right.
And so I've already been using the at SAM D 21 G 18 microcontroller for the PID guitar. And so I kind of had to like, pause, work on the penetrator and get this working so that I can get done for DEF CON.
DEF CON ends in August.
In August. Yeah, yeah. So let's go on up pretty quickly. Yeah. And so I took the microcontroller. And I took that breakout board I made and I bought a couple different screen modules that are spy, you drive them with a spy, the spy bus. And the one I really liked was the SP 7789. LCD. This one, there's like that's like the controller that's on it. But usually 7789 LCDs have higher pixel density, and they're brighter and more vibrant than most these other like low cost LCD modules. So this one in particular is 1.3 inches and di N, di angle. And it's is it diagonal?
I think I've heard that before, but I don't know if that applies on the diagonal.
Yeah, on a diagonal. I think that's what it is. And it's 240 by 240 pixels and resolution and spy addressable. So I got that all hooked up. And there's plenty of people out there that have already gotten like code to make that communication work. Yeah. And so it's using the hardware spy on the 80s, AMD and the DMA to just like shove all those bits out. Okay,
so you've just writing to a buffer in your memory and then it takes care of it. Exactly. It's
even simpler. You just call it a command. Oh, that's awesome. Yeah. And it's fast that SAM D is fast enough to where you don't get any observable screen tearing, right? Because I've written my Pixel driver, because Doom guy's face is actually way smaller than 240 by 240. And so to save program space, because all his faces are in, in, in program memory, I actually see them as like 30 by 30. Arrays. And then there's like double call pixels, it doesn't double call pixels, actually take a take one location, and then I draw that as a rectangle on the screen. Or it's a square, I guess, you there's no square function that you call a rectangle function. Sure. And so it just basically just draws 30 a 30 by 30 matrix of squares on on the screen. And it seems to be plenty fast enough. And that doesn't take up a lot of program space to to implement. So I got that working, I'm like, Okay, so I've got spy working. And I'm only using like 6% of my program space. So I've got all this space in the world to add more features, right feature creeping. And so the interface with the microcontroller from the outside world like that the Sandies, they support USB out of the box. And so I put a USB type C on it. And so what I'm going to do is you will be able to actually sniff the I squared C bus on badges with this, huh? That's going to be the idea. So you plug Doom guy into your into your shitty add on header on your badge, and then you connect USB up to your computer and you get a comport and it just spits out the adequacy data. got, oh, it'd be useful for hacking. It's like a hardware hacking, shitty add on kind of thing.
You know, it would be really funny if you use Doom guy's face as like a, like a line break indicator where like, if you're looking for a certain packet to fly by then like if his face does like a certain animation, you know that that packet came through?
Yeah, you could totally do that with this. The. And I started looking into more like, reference designs for shitty add ons and stuff. And there's a a EEPROM shitty add on reference design. So if you make a fancy should you add on that you want like something to be able to control? Like, how do you tell the badge? What should you add ons plugged in? Right?
Yeah, is there like a protocol that someone's created for that? Yeah, there's
a couple different ones out there. The The one I'm using is the and not XOR. One. Basically, you can simulate a, if you have an EEPROM on it, you can say like, Hey, your address zero is like your address zero is like the DEF CON year. And then address one is your ID as a maker. And then the second address is like the shitty add on type. And then you just put data after that. So I'm going to simulate an ice course that I squared C. E prom with this microcontroller. And that way you can actually like, you can dump data, the microcontroller can dump data into that EEPROM. And if someone wants to do something with it, they can do something with it.
Hmm, cool, isn't it? I thought I saw something not that long ago, like the shitty add on is getting an upgrade where it was four pins. And now isn't it going to a six pin connector?
It's six pins. And the only difference is they just added those two new pins are GPIO Oh, okay. And so most badges are just like, alternating those high for like half a second. So you can run LEDs to your shitty add on and that should and those LEDs alternate. That's what most people are using them for. Got it. Now I have those GPIO hooked up to my microcontroller. So we could do some funky things with that. Oh, I'm done. And I always thought it might be interesting to like, maybe if you you you had your serial port open and you can type in godmode eyes go yellow, right. And the Doom SEO turns into an ICRC master. And then you could do you could send commands on the I squared C bus. Now I don't know what would actually happen to most badges if you decide to put too high score see Masters on the same bus but hey, that's not my problem.
Yeah, I liked it. That's great. That's a good way of handling a situation you don't know. Exactly my problem.
It's not my problem
that's I wait but if you have to ask your seed masters Wouldn't it just yank everything to ground? You went super robot there. Oh yeah. Like that's that's mo to magic. I should record this. Now rah rah rah i You're unintelligible
and we were talking about the Doom shitty add on. And oh, yeah. So the design is almost complete. I got the, like the tech demo, I guess, working on my desk. It's actually running right now I can show you the over the webcam. Nice. And I'll post the video for everyone to look at. If you follow me on Twitter, you've probably already seen it. And I got most of the hardware routed. And so I'm going to probably order the prototypes. Hopefully tonight after the podcast. That's that's the goal. Awesome.
How many getting?
So prototypes? I'm going to get? Probably about two or three. And then we have a production run scheduled for it. And it's more than two or three. I don't know the exact number yet. Nice. So more than 50, probably, but less than 10,000. And then I got an update on those smart LEDs I've been testing. Those are the APA one oh fours that have a higher temperature reflow rating. So I finally got the reels in. And I've designed some Arduino shield boards, just to run through the app and just see if they work, right. Yeah. So I put the LEDs into inventory and press go on the Arduino shield board. So hopefully in about two weeks, I get them back and I can just pop into an Arduino and run some code I found off the internet and it just works. Right.
Yeah, that's exactly how it's totally every time. Right. Yeah. That's but actually that's sort of how it worked with the Doom add on, right? Yes, it actually did work.
Yeah. Well, it took a little bit more hunting around finding the right library, because I wanted one that was fast. Use the DMA. It all that good stuff.
Right, right. Yeah. Did you just out of curiosity, do you scrounge it off of someone's GitHub somewhere?
At fruits? GitHub? Really? No, they actually just recently updated their graphics library for these LCD modules to use like the DMA. Yeah, so yeah, it's pretty quick.
Yeah, I some of the first images, I saw that there was a little bit of screen tearing, and then you did some upgrades and it just all gone.
Yeah, there's a little bit of screen tearing, especially when, like, Doom guy moves the space a lot. Sure. But it's acceptable. You won't you don't really notice it. I I say I didn't see any, from the stuff you posted on Twitter. It was just like, Oh, good. Yeah. Looks great. Yeah. And on that, though, I'm going to write a tool. I hopefully I can have time to write a tool should say, No promises, right.
Six months. So now you're right into?
Yeah, yeah. Six months after DEF CON. You're right, right. Yeah. So you can take a GIF, it's gift people not GIF. You can take a GIF and automatically, like resize it and crop it and build out the correct memory structure that you can just paste in the code. And that way you can put your own things on it. You can make your own doom guy. Yeah. So Doom guy is not really a gift. He's just like, a series of PNGs. Yeah, but in the code, he's just a big, you know, see data structure. There's nothing special about it.
Yeah. Well, I mean that yeah, that add on had one thing to do. Yes. Now it's an feature creep mode. Hey, that's a major function down. Yeah,
we I didn't expect basically in one weekend to get the main functionality of it working right away. I started Like to bang my head on it for like, three or four weekends.
Oh, congratulations. Yeah,
thank you. And so there is a penetrator update though, the software side is going really well all the low level stuff is getting where it needs to go. The great thing about the SAM D chips is is a lot of spy like buses that come like Sir comms, there's like six of them in the SAM D 21. And so you can make those be like i square C or spy, or there's some other kinds of UART, I think you can make them UART as well. And so we have a couple of those with DMA running. So like running out the serial lights, and then doing the serial switches and stuff like that. That's all working really well. And we've got a hardware plan for it, that I've been designing all the parts for it. And kind of have we have a really interesting way of mounting the board. Now. I can't say too much about it yet. But once we get closer like once we actually get a physical board made and start showing it off. I'll talk more about how it's been melted. It's very interesting. And
I like I try and take technique is secret.
Yeah, well, it's something that no one's really tried yet. And we're like, well, it could suck.
We're hot gluing it to a giant piece of metal. Yeah, yeah, that's what double sided tape and we're getting closer.
Now now farther away. Okay. Yep. Chewing gum.
Chewing chewing gum. That's, that's tar.
Yet the use? Bubblicious because if you use something else, we void the warranty. Oh, got it. Yeah, sure. No, I'm completely serious.
But you used to use pen studs, like the ClipPin pens. Do you not go that route?
No, not at all. We those ended up being a pain in the butt.
Get well yeah. Good. pain in the butt as in like he didn't want to deal with a machine shop. Right?
Yeah. And they they're really good at that's like the only time you need to like put the board into whatever it is. The perfect for that. Trying to remove PCBs from pen studs. Is like you just flex the board so much. Oh,
yeah. A lot of most of those pen studs are there. For one time insertions. Yeah, yeah. But they are really good if you have to do rework or anything like that. Makes sense? Yeah. I've used them before on some designs, where once the board was in, I was never going to take it out. And it's just, it's awesome. It's just click, and it's there. Yes,
it's great for assembly. It's terrible for disassembly.
You know, that's, that's something that I feel a lot of a lot of companies neglect to think about. Maybe that's pompous to say that but but like they make a lot of products are not designed to be fixed. And that's just a pain in the a pain in the ass. You know, it's not it's not fun. I dealt a lot with that with audio gear. When I was doing repair work. And I we've talked about that before. But like, there's specific companies that if I saw their product come in the door of my shop, I was like, Oh, God, no, because
because it's like, like, go to Guitar Center and just buy a new one.
Well, yeah, I can. No, oh my gosh, I can't tell you how many times I've told people is like, you paid $150 For this thing new, it's going to be $50 for me to just open it up to look at what the problem is, you know, because because of how long it would take, especially with a keyboards and crap like that, you know? So yeah, but pen studs. Yay.
There's probably some pens, suds that are good for taking stuff apart. But, you know, we're gonna go with like, kind of a bracket design that screwed together. I thought you weren't gonna share the secret? Well, we're not telling you where exactly it's been melted. So that's behind the screen up in the in the head. top part. No, no, that is actually a really good idea though. You actually, you actually don't realize how good of an idea that was? Because we came up the idea. Oh,
it's a good idea because you came up with it. Right? Well,
because the screens already have a metal piece. That's gotta get machined. Yeah, well not machine is CNC, but they get pressed, and they have studs on the back ready for mounting PCBs on it. And so we actually thought at one point hey, let's just mount it there because then that way we already have we don't have to make another metal plate. It's already got a metal plates and shortens wires stuff, but we came up with a better idea that We're going to try. And we're surprised no one's really tried it before, but
we can I take a guess. Okay, there's two places in mind, but I'm only going to call out one. Is it on the back of the swinging coin door? That that opens up?
No. Okay. No, it's not.
Because like you could swing and open and have access to the board right there.
Yeah, it's a good idea. But there's a lot of stuff on the back of that coin door.
Okay, the last time I dealt with one of those coin doors was on a, I had a Street Fighter stand up arcade. And there was not a lot of stuff on the back of that.
Yeah, the if you actually have coin mechs there's actually quite little room for like, if you had something else hanging out the back foot to swing open.
Do most manufacturers buy those as like a single unit and they just slap it in?
I think they all come from like one place or two places.
That makes sense. Yeah. I guess those things you just apply power to them. And then there's another cable that says coin was inserted and goes to your board?
Correct? That's usually how that works. Okay. Yeah. Because that because with that,
with the streetfighter one I had there was a spring that was inside the coin door, and I would just open the coin door and just slap the spring with my finger and it will just add coins. Yep.
So how it works nice.
And the streetfighter standup I had was a miss Pac Man. And it was just somebody at one point in time just re skinned the entire thing. And I you know, they sold those games as just boards, so they just put it put streetfighter in it reskin it, but if you open the back door, it still had like all the instructions for Ms. PacMan in there.
Yeah, that was actually more common than you think. And actually, in the pinball world that happened as well, not as frequently as arcade machines, but they would sell them as like upgrade kits. The one of the pinball machines I have is a Congo from the hits movie in 94. Right.
Was that 94? Yeah. Oh, wow. Okay,
it's by the same person that did, wrote Jurassic Park. And that was 91.
Do you mean that? They were like movie? The books? Michael Creighton, I think is his name.
That's right. Yeah, he wrote Congo as well. Okay, I'm gonna look that up just in case, but I'm pretty certain that I am
correct. I don't think it's 94 I thought it was later than that.
Yeah. microcracking wrote Congo and Congo movie, I think is 94.
Okay. Yeah, reminder. 590 to 95. Wow. Okay. So that your your game has like, all of the like the sound clips from the from the movie. yells at you the entire Yeah.
And so when Congo came out, they thought it was going to be the next greatest thing ever. Because like Jurassic Park made a crapload of money. And Congo not so much.
Yeah, well, for obvious reasons.
Yeah. A me hungry I actually really liked that movie. And I actually liked the pinball machine. They Williams wounds Valley was the company who made the Congo machine. And they, they didn't make that many. And they also because like, it's just the movie was a flop. And so they didn't sell that many Congo pinball machines. And so what they did is they're like, Well, you know, it runs the same board set as these other machines that are coming out the same time. And so if you buy basically an upgrade kit, you can you basically buy a playfield and new graphics and new ROM chips, and you just swapped the ROM chips out, put new graphics on your machine and slapped this new boards, big playfield in then you can have like a attack Mars, and which was a lot more popular for game. Hmm. And so a lot of Congo's met their fate as turning into other machines, it's actually Kongos X, they only made like 1400 or something like that. Kongos which is not a lot like at the time they were making like 10,000 of something and that's when they made 1400 or whatever. And then probably like half of them got converted to other machines. And so actually, Congo is a really rare pinball machine that like when I got it I got it for free because no one wanted it. But now like people want this machine
it how much would one of those go for reference?
I think one in really good shape right now is about four to five grand. Last I checked, okay. It used to be free. Like you couldn't give them away
with the so just out of curiosity, what's like the most complex pinball machine game out there.
It depends. If you just want like one that sold ever there is a game by Jersey Jack pinball called. It's there. What is it's the why can I remember the name of that movie? It's a really, really popular movie.
And I guess by complexity, I mean, if you look at most pinball games, they're they're just like, lights everywhere and all kinds of ramps and Max and all kinds of stuff that just confuse you most of the time.
Okay, so I'm talking about like, if you opened up the playfield, you would like, blow your mind. Okay. Wizard of Oz. Wizard of Oz. And it's because there is so much stuff on top of the playfield. And then underneath there's so much like, Max. It's crazy to look at. They just want a wide bodies. It's even wider than a normal machine. Hmm. Okay. In that machine, I feel bad for people who have to move that thing around.
What is probably heavy I mean, they're all right.
They're all heavy. But this is a as a very heavy pinball machine.
Oh, yeah. I'm looking at pictures of it. That's crazy.
Yeah, that's a the mechanicals on that machine are very impressive. Like, I've actually there's some mechs on there. I've never like when I played it. I've never even gotten the actual like actual weights, because I've never gotten that far in the game.
It sounds like it sounds like people just going crazy just designers given like free rein to just put all kinds of crap in there.
Oh, yeah. Yeah.
Oh, yeah, that's that's normal. Yeah.
I would say that some classic games that have a lot of stuff in it. Like, oh, what is it? There's a it's an old godly game that this comes to mind for some reason. Gottlieb's Waterworld for the hit movie Waterworld, right. And they didn't make
a pinball world picks really bad.
No, they just they make all the movies. That's the thing. And that machine, there's not a lot of them out there. I don't know if they ever made a production or how many are out there. But it's got a really cool mech for the like for a boat, I guess. Okay, like rotates and stuff. That's a really cool neck and I've never seen underneath it, but I guess it's gonna be pretty crazy. An infamous infamous mech in pinball world is off the Dallek or is it the time? No time expander the time expander from the doctor who machine because it's got like it's a mechanical device. It's got like a big motor with a screw. So the whole thing like a screw drive. So it's got a lot of force. Yeah. Right. And so but it's got like, switches to like check where the levels at because it's not a stepper. It's just a DC motor. And so if one switch fails, like the whole thing messes up. And, and they have like a safety switch. Like it's the only pinball machine I've seen that you can't play with the glass off, because it's got a safety switch that disables the mech. So your fingers stuck in it, because it would like Crusher,
just rip it apart. Oh, yeah. You know, back to that Waterworld would. I think it's funny because I'm looking at pictures at it right now. And it's clearly from the movie, but everything about the playfield everything about the mechs and everything is it looks like a comic book. And it's just like all hand drawn. The only thing that's movie is the backdrop that has Kevin Costner's face. And that other weird dude who smokes on the ship all the time. Yeah. They only got like part of the license to use stuff from them.
It's actually a really good pinball machine. It was at Texas pinball fest a couple years ago and I played the hell out of it. It was a lot of fun. Nice. I think it was it was one of the Gottlieb's last hurrah was before they went out of business. So it's fun machine to play.
When are you going to release a pinball machine?
Um, after the penetrator
sometime sometime in the future right
sometime in the future you ever know that's great. Ah, don't get me started on that machine. Oh, is it is it crappy? No comments.
Oh, did they did they steal your your board or something?
No, no. Okay. No comment on that machine. No. Okay, mainly because I haven't played it.
Okay. You want to give it a fair chance?
Yep. Yeah, um, you should know about the pinball machine I designed back in college.
The set reset vector. Yeah. I saw it in your garage when we were brewing beer. Yeah, I saw like a wooden frame. Yeah. Did it actually know a point? Somewhere? Oh, you throw it away.
Yeah, mainly because it was just old. And I've learned so much about pinball design since then.
I mean, it looked cool. It looked for lack of better words, it looked retro.
And that's kind of the idea. Maybe someday I will go back to it. But the penetrator takes precedence first. I'm better at building hardware to for other people to build machines and building my own
share. Yeah. Is there a Evil Dead pinball machine?
No, there is not. Hmm.
Well, that sounds like there needs to be one. Yeah. All right, let's move on. Okay, so this last week, I started looking back into more on the macro app, and kind of what I want to do with a V two of this. So I've got the macro amp working, like I discussed last week, and nothing particularly wrong with it. But I just want to make some updates and see if I can make things better. So Mark, and I were kind of toying around with the idea of like, what if we made it a four layer board and did internal trace routing and played around with that, and one of the things I've never done before is a surface mount technology with this kind of high voltage. So I think this is a great little project to get into that. And mainly, one of the things I was looking at this, this last week was
how I want to handle all the high voltage with surface mount, but also using fewer new tubes. Although all said and done, I think I'm going to stick to the general structure that I already have
So I designed this original one with all this extra capabilities to to do direct plug in from a moving magnet cartridge or a what have you, there's moving magnet, and there's, I can't remember the other one now, whatever acid have, I think, right? Directly from from a record player head. So we're talking about like, micro volts worth of voltage and stuff, you know, I looked into it a little bit more, and I don't want to get that wanqi with it. And like a modern, most modern record, players are gonna have their own preamp in it and spit out live voltage anyway. So I think in v2, I'm just going to strip it down and make it more simple, where it just has an input, it'll have control, it'll have volume control, but just just do light input, then adding all the moving magnet preamps stuff is great. And ra filtering is cool and all but I did that and I don't want to do it anymore. So yeah, I'm gonna gonna redo that whole circuit and redo the layout and keep it with two new tubes, and just kind of fine tune the gain on everything until it's all good on there. You're creeping it. That actually yeah, this is probably the first project where I am decreasing that. Well. So I'm I'm doing what happens when you remove something and then replace it is that a side creep? A lateral creep, Alex like creeping side creep. So I am going to side creep on this. So actually, last weekend, so I'm helping a buddy design a guitar amp right now. And we decided what so we're sort of doing a traditional kind of design, but adding a whole bunch of unique twists to it. So one of the reference designs that we're kind of building off of uses a think it's a five Henry choke, that comes right off the power supply. So the main rectifier comes in, you rectify that to high voltage and then it goes through a choke to a capacitor on the other side of the choke. And you make a tank circuit basically, that just has really great ripple reduction. The thing that sucks about it is you have to find place on your chassis to put a giant inductor. They're not cheap, and they're sort of just a pain in the butt to find. So I decided let's go and make a solid state variants of that of that choke and so we decided to go with a Gyrator circuit. And if, if you haven't played with a Gyrator circuit, they're actually pretty legit. It's a simulated inductor. So if you, you know, there's there's a ton of different ways of actually implementing this. But by using a voltage divider, a capacitor and some kind of past device like a MOSFET, or something, you can actually simulate an inductor. And by combining the the correct impedances in there, you can actually pick, you can basically make your own inductor that has both the same resistance, and has basically whatever inductance you want. So we created a simulated inductor that has about 90 ohms of resistance, which is pretty similar to the five Henry choke that we were doing. But we upped the inductance to 47, Henry's, so you get tons of ripple reduction, you don't have to buy a giant choke, the only thing you have to really deal with is the fact that you're passing now all of your power supply through a pass device. So you have to deal with the heat. But we have it in such a configuration that it's actually not delivering a ton of current. So check out a Gyrator they're pretty legit. And I think in the new macro amp, I'm going to do a Gyrator this time around as a surface mount thing, because I have a giant choke that's inside the the chassis right now. And it's just, I don't need it. It's just, I did it because I did it. And yeah, now I'm gonna replace it with a Gyrator. That's the whole kind of point with the second Makram. So hopefully soon. So I'm ordering the PCBs from my buddy's amp, hopefully this week. And so we'll be able to test out that Gyrator, which I think the input to that generator, we're doing about 430 volts, and we're gonna pass maybe 50 to 100 milliamps through it. So I think we're going to actually take that pass transistor and just bolt it to the chassis with a, like a mica spacer on there, which I think is plenty enough to actually deal with the heat on that. We. So, kind of interesting, this is
what is that would be that's 40 watts.
40 Watts, like worst case scenario, okay. Yeah.
But actually, often Well, I see. No, no, but
but the thing is the Gyrator. The generator only drops a few volts. So okay, okay. Yeah, so it's not, it's not 41 It would be 40 Watts if you shorted everything out. Yeah.
Yes. Okay. Okay, that makes way more sense now, because I'm like, I'm trying to think I'm like, man, 40 Watts is still like, you know, Oh, that's
right. That's a shitload of heat. Yeah, no, no, no, no, most of the time, you're going to be dropping somewhere in the range of like, eight to 10 volts across this generator. So yeah, yeah, like you can, you can get a one watt max. So so the thing, actually, one of the things that kind of sucks about, excuse me doing a simulated inductor like this is you're usually actually going to drop more voltage than and an inductor will. But the cool thing about it is you won't get, you don't get a lot of the what's it called? oscillation that potential for oscillation, because a simulated inductor is not actually storing any energy as a magnetic field, whereas a real choke actually is storing energy. So the Gyrator does the same job as an inductor. Because it what it actually does is it takes the capacitor that's in the circuit, and it flips the impedance of it. So you flip the impedance of a capacitor and you get an inductor. So it's doing that, but it's only doing that because of its amplification, not because of actually storing in your energy. So if you've ever turned on a circuit that has a big choke in it, or turned it off, suddenly, a lot of times you can actually hear the choke, it will pow like that, because it's just oscillating with the tank capacitors that are around it. And maybe, maybe that's an indicator of a poorly chosen choke. But still, it's, I don't know, this is a cool little circuit. And yeah, you know, you don't see this very often. Probably because it's kind of expensive, and people don't use chokes much anymore. But it's still kind of a cool little like, side thing. You know, you spend $30 on a choke or two or $3 on a Gyrator you know, you pick or so yeah, I want to I want to implement all of those things in the in the new Mac ramp. So that's, that's the lateral creep going on there. Or the side creep,
I'm sorry, side creeping man.
Yeah, so and then, you know, last week we were talking about that Fredman clip that I purchased that 3d printed microphone clip. And so over the weekend, I decided to actually give it a try and really do some stuff so I just made some really crappy recording. So you can hear me play some goofy metal licks on my guitar. And here is a test recording that I did. We're using two microphones and the Fredman clip so yeah, that was That sounds pretty good doing some guitar stuff.
Yeah, so so I can't remember exactly. So I will, instead of using two sm 50 sevens, I had a spare as in 58 lying around. I don't have 250 sevens. And I didn't want to go. Tell. Yeah, sure. I didn't want to go spend another 100 bucks just to try out this for admin clip. So I had I don't even know where I got this mic. Seriously, like I moved up here and a microphone just spawned somewhere. So okay, the I mean, the good thing is the estimated two microphones
really love each other.
So the funny thing is this, my sm 58 doesn't actually have its XLR connector on the back. I don't even know where I got this sm 58. But it's
also the most at the back. So the two microphones that loved each other must have been from Alabama. Oh, jeez.
We're not going there. We're not touching. So I thought you know, I thought it was going to do so a whole ton of extra noise to just alligator clip. You know, raw microphone wires in and it didn't. So
great. We recorded a lot of podcasts over alligator clips.
We also record a podcast with socks over microphone like legitimately socks that were just to be done that.
I think my favorite was when we recorded your audio with that ribbon mic. Yeah, that was with the transformer taped to the mic. Boom. Yeah, but
hey, the mic had magnet. So we just stuck it to the boom. And it totally worked. Yep. Yeah. I found that like the other day, it was actually at work because I was showing it to people. And we are still do some time to make a second copy of that. Yes, that will happen. Cool. So those are some things I did.
Yeah. So onto the RFO. Oh, I sold me to get you the clip I printed for you. Oh, that's right. Yeah. Yeah. Parker printed Redmond clip I printed for you. You know, you got a whole stack of stuff I need to send up to you.
You should you should send me you should send me that. That clip. And then I'll do another recording. And we won't be able to tell the difference. No,
I just want to see if it works as well. Like it actually holds the mics just as well.
Yeah, you know, and I know I was complaining last week about the 3d printed stuff. I left it I left the clip on the mic. So the clip has been holding the mics for days now. And you know, it's fine. Everything is okay. So
world hasn't burned down yet. No,
I I'm still I'm still a little miffed that is 3d printed, but it's all good.
And 30 years, you're on your deathbed, or at 60 years. I don't know how old you are. And your your son comes up and is like, whether there's any regrets that you had pop ups Stephen, and he goes, 3d printed Fred mini clips.
I bought too much 3d printed crap. I only bought one 3d printed crap. And it worked. So maybe I shouldn't complain. Yep. Okay, well, actually, well actually one thing about that, I guess the part that that did make me a little upset is after we did the podcast, Parker spent two seconds and found a 3d printed a 3d printable model and printed it in like a few hours or whatever after the podcast and I was like ah should have just if I just looked I would have asked Parker to just print me one you know yeah
whatever. Yeah, I think I started the print at like 10 o'clock at night and then by the next morning my printer was done. Right? Yeah. So
fast shipping right? If Yeah, if I need another one all you just
need to like invest in a you know, $600 for a printer, spend a couple months tuning it and then
I watched you to net that thing. Not only did you spend a couple months like you how many different cooling shrouds Did you print for that thing? It was four or five, five? Yeah, for sure. And you just
keep printing more elaborate ones that let you print more elaborate things, thus more elaborate cooling child?
You know, that's okay. So that's the biggest thing. And you've mentioned this multiple times, it's like you get a 3d printer. It's not an it's not an inkjet printer. Like, you can't just like, get it and then press go like it will not do that.
You are correct. I've, I put a lot of effort in making my printer like that though. Like, there's right now it's, it's set up to the point where I just log into Cura, the 3d slicer program I use, and I seriously just hit print, the printer automatically turns on, on the network, and prints don't have to do anything else.
Right, right. But how many hours did you put into making that happen?
Ah, as I said, a couple couple of months of random afternoons doing it, because it's mainly upgrades like putting in a auto z. So you don't have to, like level the bed. Right? You know, doing all those little automation things. So you don't have to make sure that beds level or anything like that, or putting an enclosure on it, so that your temperature stable. So you don't have to watch the print to see if it comes loose or whatever.
Yeah, this is also exactly why, like, even $600 doesn't get you a thing that gets you the things right.
Oh, no, no, no, I would say like three grand is what if you want something that you can just like rip out a box and put on your desk and go, like three grand is why would pay?
Right? Right? Well, you know, the thing is, it's the same with like any CNC or a mill or something like that, it's not going to come out of the box, and you just type in steel, and it just cuts steel, you know, like it doesn't work that way. Like you have to still we
got our we got our new picking places and stuff. It's like they you have to check them out the box and they have a big like, lock on them that says you can't remove this unless micronic shows up and removes it and you know, calibrates your machine for you.
Yeah, yeah. With the high speed mill that we purchased at work two months ago? Well, I mean, we purchased a long time ago, it just showed up at work two months ago. It had, like, it didn't come with a license file, and it had a countdown timer on it, and you get 200 hours with it. And if you don't get the license file, then it just shuts down. And it just goes into limp mode, like you'd want even do anything. And the license file has to be provided. Once the bank says yes, we're gonna pay for this, you know, and payment. I mean, when you when you spend that kind of money, it makes sense, right?
Yeah. I just think it's funny that it's how they handle their hardware DRM kind of like thing is they'll still ship you the machine costs. But there's a little tiny, you know, 16 character number. Yeah, you just, it just locks you out. Yep. Yep. Okay. Are for time, right?
Yeah, let's get off.
We'll speed through these since we're already at 50 minutes.
Oh, my gosh, right. 50 already only we've been side creep and a lot. Yes, I
creep in all the time. So the Google glass glass whole thing is coming back with the glass Enterprise Edition to faster and more helpful. Now they say more helpful, like it was already helpful to begin with, but we know it wasn't.
I saw one person ever wearing Google Glass. And I'll be honest, it actually infuriated me because like, there was like, four or five of us around a table and we were all having a beer. And like, he would just start talking. But he was talking to other freaking people or he'd be like, reading his texts and stuff. Like that'd be like, dude, like, we're all here to like, hang out and have a, you know, have a beer together. Like, do you want to do that go somewhere else?
Yeah. I think I saw a lot of people at Maker Faire when these came out. Back in like, what? 2012 2013? Yeah, ish. I think that's the one time they came out that a lot of people hadn't there. But that's, you know, San Francisco. So the so so basically, Google canceled Google Glass. And they basically started a new division of Google Glass to do industrial, basically industrial augmented reality, which I always thought I went to reality would be really good at.
Right? Especially like inventory. Like, if you look at a part and like on the glass, he would show you the part number. Yeah.
Inventory is like, everything already has barcodes on it so you can easily do computer vision and figure out what it is or where you're at in the warehouse. And like say, hey, I need to go find part a. And then the Google Glass goes and just highlights the box where it's at. Right? That take that just taking the mental load off of people reduces. Basically stress and all that other stuff. It's like, why these really fancy? Auto, auto cruise control stuff? I'm not gonna call them auto pilots, because they're not auto pilots. Tesla. Do you have feelings about this, don't you? Oh, yeah. Oh, yeah. They call it autopilot. And then it doesn't automatically pilot you anywhere. It just keeps you in the lane most of the time.
So I remember macro fed, we had multiple chats about like, the future of manufacturing and, and the idea that an operator or a solder tech could be wearing goggles, and you know, they put a board down on the table. And it could say, like, oh, you know, this transistor gets soldered here, and you need to inspect to this class and like it would show information about the board. And they're like, Yeah, I think that's
where this is really going to shine that yeah, that's where augmented reality. That's where the money's at is making people's lives. Augmenting humans is what I always say, Yeah,
you know, I could see it too. Like, if you're on an assembly line for, say, Toyota or something like that. And you're a guy who needs to tight, tighten a bolt down to a certain torque, like, if, if the glasses that you're wearing could be connected to your torque wrench, and like, you would torque down a bolt. And you know, the the torque wrench would say I've reached the the correct torque a would like highlight the bolt and be like this one is done. But you need to go torque that one over there. You know that? Yeah. And actually,
like, if you were doing like the torque pattern, or like, oil pan or whatever, it highlights the ones that you've already finished. Right, right. Yeah, that's a really good application for it. Because usually, right now you pin them. Right? That you've talked to spec?
Yeah, exactly. But if you if the glasses could do it, and then it could, you know, it could send a report to, you know, everything is done. And it was done in this amount of time. And that's some serious manufacturing stuff.
So it's a really good idea. The only if you watch the video, there's one section, which I don't like, it's like a doctor is wearing them. It has like all the information of like the it's like, I don't know how I feel about did you torque
this patient's liver to the correct settings?
I don't know how I feel about your doctor visit being recorded and stored in the cloud somewhere.
Also, I don't want the doctor like I don't want it to like highlight something and the doctors like, oh, that's what that's called. I didn't know that.
I'm just thinking like, the doctor walks in and like, scans you and says, yep, that's human.
You're alright, it says you're a human. Yep. Also, I don't like that's, that's a nasty topic to breach, but like having all of your medical records be available for them to access at any time. That's some privacy issues.
Yeah. On the other hand, though, that would probably make diagnosing people a lot easier.
It is one of those lip board with
double edged shorts where like, I don't know, because I you know, I've had a lot of mental issues earlier this year. And like, whenever you go to a new place, you get the sign like eighth form saying that, yes, you can share my information with my other doctors on this list. And then you have to go like, update the list somewhere else saying that you added this doctor, and it's just like,
a, it's a lot of work? Yeah, sure.
Having a like, nationwide or worldwide database for like, that kind of stuff would be a lot easier. But then you get into other issues, like who can access that database? Can your insurance company know you're in know that that stuff? Are the government know it? Yeah, it's one thing. It's like, when you do like those 23andme He's like, to get your DNA stuff. It's like, oh, now the police can like audit your genome and figure out if you're like related to a serial killer.
Was this Minority Report? No. I mean, that's indicators
that that someone got like a, like a 23andme DNA test and showed up in a police report. And they found like a serial killer through being related to that person.
No lie. I didn't know that. Yes. Yeah. Yeah, read the fine print on those. They.
Oh, 138 pages. Right, right. Yeah.
Yeah, that one that you just signed in and said, okay, whatever. Yep. There's a South Park episode about that. It's pretty solid. Oh, yeah.
Have you ever watched South Park in like, ages?
I am surprised that it's still on. Not that I'm saying it's bad or anything like that. It's just like, it's just been on forever.
Yeah. I the last I think the last South Park episode I watched was the episode where we're it was on the last federal that last presidential election.
Okay, like I actually watched you mean like with the one that the Trump whole thing? Yeah. Yeah. That was like an entire season of them doing. Yeah. So I actually watched that season. So those are really good. And then like,
we're gonna get political on this, but bear with me. Bear with me on this one people is they clearly had it set up that that season, where like, Hillary was supposed to win the election. Oh, yeah. Because like the episode that actually aired they had to like rewrite it. So what's the what's the teacher's name? Mr. Garrison? Yeah, Mr. Garrison wins. Right. You
will Mr. Garrison was Trump. Medicare's? Who was great. The creators actually came out if I remember. Right, they said they they regretted doing all of that. Oh, yeah. That whole season.
I thought the season was great. And then that last episode was just terrible. And you could definitely tell like the script was rushed because they had to rewrite it for like, the animation was really rough and stuff. Yeah. I just thought it was interesting. Like, I would have just like, had Hillary, when does it really matter? That it had to match real life? I don't think it had to matter.
Yeah. It was a weird season. That's for sure.
Yeah. All of their others. Yeah, it was. Yeah.
So we're going really off the rails tonight. Oh, yeah. This
is the side creep episode is super. Great. So
hey, guys, speaking about potentially getting people to steal your information? I found a an article. That was electronics. Yeah, that was yes. Pretty solid, right. It's the the title of this article was a kit converts Raspberry Pi into Alexa type home automation system. Which, like, as soon as I saw that, I was like, oh, yeah, I gotta look at this, this, this is gonna be this is gonna be really good. And it's interesting, because it's a kit that's available on geek.com. And if you've been to geek.com, they got a bunch of cool stuff there. And they actually support some YouTubers that I like to watch. So like, you know, this is no bad, ill will towards geek.com. But they've got this kit that basically allows you to create an Alexa type thing with your Raspberry Pi. But it also has some online courses that you can take to really get your feet wet with home automation. And
so so we're not sponsored by them. Now, but the deal is the funny thing is though, I say that though, but like this deal, it says ending in six hours will expire before this podcast ever comes out. So it doesn't matter. Is the complete Raspberry Pi Alexa A to Z bundle for they say 94% off. I'm like, what? That's a 29 bucks.
Yeah, okay, so 29 bucks. I mean, it's not going to come with a pie. You gotta you gotta supply your own. But you get the you get the classes and stuff. And they have in the article, I was reading that there was a sentence in there that said, this can be understood by anyone says kijk six Shep, regardless of education or training, and I'm just I know what needs to be connecting your house to the internet of things if you like, are going from scratch. You know,
we should do this. Oh, I think I think better house could be the one that goes. I think Mac fabric can throw down 30 bucks for I think you should do it.
I should do it. Okay, okay.
I think this would be good idea.
I've got an extra pie lying around. So if you want to if you want to have 12 meg Fed wants to get me a kit. Like, let's, let's take the classes and see what it has to say. Yeah. You know what, were dogging on them right now? Maybe? Maybe? We should do it. Okay, we'll give me a kid. Yeah, then we got we can talk about it.
Yeah, so I don't think you'll be the next podcast. But we'll definitely we'll have to do it. Because it's only like six classes. I wonder if you can do it in a weekend.
Hey, you won't you only have six hours left to get this 94% off deal, dude. So I didn't I didn't look at all the contents on it. What does the kit fully come with?
It says it comes with I think it's just a class that you're buying. Okay. And so
it actually comes with some hardware doesn't come with like thermocouples or something like that.
I don't think it does. I think it just comes with I think there's just the classes. Yeah, it's just so courses.
I thought I read somewhere that it was actually coming with something. It's interesting that they would label it a kit, if it's only online classes.
Oh, it says bundle, not kit. Ah,
well. Okay, so the article from electronics weekly calls it a kit. Okay. Okay, so maybe that was incorrectly,
right. I think we should try this and just like see like, how far we get. And like, because we don't build IoT, Raspberry Pi Alexa combined things.
So, one of the things I've always enjoyed is when it's the idea of some dumb IoT thing that tweets out absolutely useless information. I love that. So,
and actually, you've been wanting to get into this. What the first one of the first classes is like, familiarizing with Python programming languages.
Yeah, Mark and I were talking about the other day, I want to, I want to get some scripting stuff to handle merging of multiple text files. And that is something that I am absolutely awful at. I don't even know the first thing about so if I learned Python from it, that would be a good takeaway.
Yeah. And so it's got so right now I know we're just like, gushing over it now. Oh, yeah.
We're, we started off with being like, this is a piece of crap.
They actually have a memorial deal. They sail right now as well. Oh, is it 96% off now? No, it says 15% sitewide off. So I wonder if you get for free? I doubt it combines?
No course it does. So. Okay, fine. Yeah, let's let's convert this. You get it for me. We'll take the classes and then we'll come back and say if it was good or bad.
Yeah. And actually, it would make great content if we actually built things. Fine. I'm down. Yeah, I want to see your tweet thing that tweets random things when you like walk by it.
I you know, I kind of wanted to just tweet things that nobody will care about. And I'll create its own FFT No, it'd be funny is to create its own Twitter handle. And push really hard for it to be a very, very, very popular thing that just tweets garbage, like nothing at all, you know, actually, no, it'd be really funny is to make a device that insults celebrities, and it just comes up with like, really unique celebrity insults.
Like it just trolls Twitter for like people who have lots of followers and just adds them.
Yeah, it adds them and maybe it could have a bank of like insults and it would just like create like these it's sausages.
It's gotta be like dad level insults though.
Yeah, stuff that wouldn't get it banned, but would also just be like, Oh, insult, but that's it, but it would have to put it but it would have to be IoT in a in a way where like, if something happened, then it would insult a celebrity. Yeah. If the temperature changes or something, you know, something or every time I flush my toilet? I celebrity gets insulted. Yes, I think that might have
that would be pretty funny.
Okay. Well, let me take this class and see if I can do that. Okay.
So the last RFO sorry, everyone, we're way over time. And this is actual engineering
as opposed to the last hour? Yeah, exactly.
It is a one page guide to fixing radiated emissions. I think this came out on like the normal social media stuff a couple of months ago but we didn't talk about I think we had like a bunch of guests in a row or something like that. And it says the A like rundown of what you should do if your PCB fails FCC CE testing. And I liked the the way it's written. It's really snarky. It's very snarky. The whole like find the aggressor. Yeah. Who what part is aggressing your your DB level basically.
Yeah, find the aggressor and destroy it. Yes.
And just like stuff, like, right here at the at the bottom here. You follow the stupid stupid advice of some vendor datasheet and split your design to analog and digital grounds, didn't you?
Yeah, don't do that is what it says. Yeah, it's a cool little it's, it's it's nice because it's not super, super dry. It's, it's entertaining, but at the same time, it actually has good information in it.
And then I just like at the very bottom knows like, because like if you have to do a new spin board spin it says consider taking your project manager drinking your your hardware schedule.
Yes. Get a couple more days in there. Yep.
Nice. Go check that out people that is it's really good. Yeah, we'll have the link. Get this guy on the podcast. Nash Riley,
find the aggressor and get him on.
Yeah, I tried to get this guy on the podcast. Yeah, that'd be cool. Maybe he listens. You never know. Hello, Nash. Riley, would you want to be on the podcast?
Yeah, if actually, if any of our listeners know him, contact him and ask if you're still listening. Yeah, well, at this point, yeah. Now they gave up a long time ago. Yep. This is the longest one we've done in a while, isn't it? It is
it is. And I think we should not make it any longer. I agree. So that was the macro engineering podcast. We were your host Parker Dolman. And Steven Gregg. And that was the smoothest outro we've ever had. See you next time guys thank you. Yes, you our listener for downloading our show. If you have a cool idea, project or topic, let's do it. And I know Tweet us at Mac fab at Longhorn engineer at analog EMG or emails that podcasts at Mack fed.com If your name is Nash, Riley, let us know as well. She'd be on our podcast. Check out our Slack channel as well. If you're not subscribed to the podcast yet, click that subscribe button that way you get the list of episodes right 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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