This week Stephen and Parker where supposed to discuss bench equipment for development and testing but got distracted by talking about homebrewing beer and Maxwell’s equations…
Special thanks to whixr over at Tymkrs for the intro and outro!
About The Hosts
Parker Dillmann is MacroFab's Co-Founder, and Lead ECE with backgrounds in Embedded System Design, and Digital Signal Processing. He got his start in 2005 by hacking Nintendo consoles into portable gaming units. He also runs the blog, longhornengineer.com, where he posts his personal projects, technical guides, and appnotes about board layout design and components. Parker graduated with a BS in Electrical and Computer Engineering from the University of Texas.
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.
Host 2 00:11
Hello, and welcome to the macro fab engineering podcast. We're your hosts, Parker.
Host 3 00:16
And Steven Craig,
Host 2 00:17
This is episode 304. So Steven, you are in town.
Host 3 00:23
This I have not been in Texas in three and a half years.
Host 2 00:26
Is it really been three and a half years?
Host 3 00:29
Actually no now that I think about it things laundry, things longer than that. No, no, no, because I've come down for one Thanksgiving.
Host 2 00:36
That okay. I was thinking that you haven't come down since you moved there?
Host 3 00:40
Well, no, this is only the second time I've come back since I've moved to Colorado.
Host 2 00:45
Yeah. Because when I went up there for that July, I was 19. Yeah, but that was you are already up there for two years at that point, right.
Host 3 00:53
Or just a little under two years. Yeah, yeah.
Host 1 00:57
Host 3 00:59
Sure. Actually, no, I was there for one year, then. Regardless. Yeah, I'm back here in Texas for Thanksgiving. And we're doing the podcast Live, which hasn't happened in a while. It's interesting to be in the same room. Yes. And to not hear like a, like a time delay between
Host 2 01:15
That and but we're still like eight feet away. And that's not you know what to say? It's we're social distancing. Oh, okay. It's actually because we need Mike separation. And this room is not the best for recording because it's all hard surfaces. It's actually not that bad, though.
Host 3 01:35
I mean, it'll get by, it gets by Well, there's
Host 2 01:38
No echo. It's not like the first three episodes were recorded in my kitchen. Were like, with a Yeti mic with a yeti room mic. And we're both. We were both like, huddled around this one mic. Like, speaking into it like to like, if one of us had COVID We were both gotten COVID. Like, we were like, right next to each other.
Host 3 02:01
It was awkward.
Host 2 02:03
Yeah. And then we then you. Well, you knew Josh,
Host 3 02:08
And I think who's our does our editing. Yeah,
Host 2 02:12
But but that was, I think it was episode three or four is when we went to Josh's studio and actually recorded like a proper, like, thing. In the first episode we did there. We had like a table, and like stools and stuff like that. Like it was like a very NPR setup. And like the next time we were like, can we just sit on the couch Josh and Josh like, Sure. Why not? We just did a couch.
Host 3 02:42
I had no way am I speaking from any kind of authority on this, but somebody asked me just yesterday that they're talking about starting a podcast and they're like, Hey, can you give me some, some pointers? And I was like, Yeah, sure. I guess I'll give you something that was like, record, like five episodes, and then throw away the first three. Yeah, start with the fourth episode. And just consider that episode number one. Just get some practice. It's
Host 2 03:08
Practice. And then after 304 Yeah. 300. For now. It's still where we are awful at closing podcasts, we can start a podcast. I mean, yeah. And close it down, though, that we have actually been getting better at that. I've noticed it's,
Host 3 03:25
We just have fun every week. And I think that's I think that's where this podcast kind of has its charm, is that you know, all of our listeners come here, and they just get to hear us kind of rant and rave about topics and engineering and technology. And we all just get to have a good time. And there's not a whole lot of restrictions in there. Yeah.
Host 2 03:47
Our marketing director. He was like, Y'all have really weird topics. Yeah, we do a wide range of topics. And I was like, should we change that? And he's like, No, don't don't change. It
Host 3 04:03
Works. It works. Yeah. Let's just put it this way. I say it works, because I haven't had a lot of people respond, talk to us and say like, your topics are really bad. You really need to change these. That's, that's,
Host 2 04:15
That's one of the things we've noticed. I mean, we've been doing this for like, what, six years now? I'm like that. Yeah, we're gonna have our sixth anniversary coming up, right? in like February. Yeah, I believe that's, um, but on that is after six years. I think we only had one email that said, like, we're stupid. Okay. We've had some like reviews that are like, Oh, it was they speak of authority about things sometimes, but they're generally wrong, right. have no clue. When I read that, I'm like, No, we we always preface that we have no idea what we're talking about when we have no idea what we're talking about.
Host 3 04:57
Yeah, so you can't claim that
Host 2 04:59
You can't claim Not one. Um, and it's like, I want general like, I want feedback to make stuff better. There's no way we were amazing out the gate, right? No, we're pretty bad, we're bad. So if you're listening to this, and you have anything you want to hear more about, or want us to improve on anything, just let us know. Because we have like, we had a, like one episode, we had a couple episodes, actually, like I left my air filter on it might in this room, and people heard it, I turned it off.
Host 3 05:38
Another Another thing to note. So if this is a shameless plug for our Slack channel, here, but if you join up on our Slack channel, and you're active on the Slack channel, there's actually a pretty high likelihood that we'll talk about your topic on his on the Slack channel, because Parker and I are on there every single day, almost 24/7, and we get a we get a lot of our topics from the users on the Slack channel. So if you have something that is really interesting, and really cool, you know, put it on there, and we will likely talk about it.
Host 2 06:10
Yep. So a long, long time ago, in this podcast, I guess it was like, I think this is this is when Iris was Mark, Head of Marketing at macro fab. And this is when we were doing the podcast in the engineering room, which was like half the warehouse. This is back when maxpreps warehouse was like 200 square feet,
Host 3 06:33
Which, which I kind of I kind of love those days, because it was a little bit a little wild west. And when they moved into the new building, they were like, here's this nice spot for developers. Here's this nice spot for the sea level people. Where should the engineers go? The corner of shipping
Host 2 06:49
Corner shipping? Yep. It's like Thanks, guys. And, and so corner of shipping is where all the sewage flowed. And so when it in federally backed up, because that building hadn't been used in like 15 years. And the plumbing had failed. They had a cut a four foot by four foot hole out of the out of the ground of the foundation and fix the pipe in the middle of engineering. Yeah. So basically, for a couple of days, we couldn't even go in that room because it just smelt like sewage. Yeah,
Host 3 07:21
We had to do to corner that. Sometimes I feel like that's the way engineers get treated a little bit. I'm not complaining about it. I'm actually laughing. But I think it's funny, because it's just like, well, we'll put them back there. They'll still do their job, you know?
Host 2 07:38
I think it's because if you, if you walk by an engineer, the engineer is going to talk your ear off about what they're working on.
Host 3 07:47
They're gonna get excited. I
Host 2 07:48
Know, I know a lot of people consider like engineers to be like, the introverts of the company and stuff. But it's because you're talking about like, sport, ball, sport, or hoops, or Yeah, so we're talking about something stuff that normal people will talk about
Host 3 08:05
The normies. But
Host 2 08:08
When you're talking to an engineer about what they're working on, like,
Host 3 08:12
You can't shut them up can shut them up. Also, at macro fab when we were doing the whole, like, back in the day with with our engineering team. I would say, you know, we were at our desks, but also we were on the floor. We were talking to other people. We were going department to department getting a bunch of stuff. So I mean, we were at our desk for you know, an hour or two a day, but the rest was all over
Host 2 08:35
All over the place. Yeah. So where I was going out with that is that was when we would, we would we would go and like, get a six pack of beer on the way to go do the podcast. And then we see when I would alternate buying the six pack of beer. And there was an idea to do like, oh, we will talk about our beer. And we ended up never doing that idea. But we are going to do it this time. Because it's a special period. It is a I say it's a special beer, because it's the first beer Steve now it's not the first beer. Steve and I brewed together many, many years ago. But it was the first beer that we did a like CO recipe collaborative design. Yes. And we actually started started in quotes because it immediately died because nothing else happened after it. But we came up with like a brewery name. And it's like, cool, like, design and that kind of stuff. So this is the original name for this beer is actually not going to lie. It's called stupid stout. And we brewed it in September 2015. The original one this is not six year old beer though, by the way. Oh, this has been we must have been on like episode like 30 at this point in.
Host 3 09:53
Yeah, I mean, it was yeah, this was new. Yeah, for sure. Yeah, we were
Host 2 09:57
We were in probably episode because this is a timber In 2015, and we started the podcast February 25. I had only been at Mac Feb a few months. Yeah. Well, we started February 2015. So you were there for six months at this point?
Host 3 10:12
No, because I I got married March of 2015. I wasn't even at macro Feb when I got married. So I started into macro Feb in the summer of 2015.
Host 2 10:23
So then then we start the podcast and 2016 then that could have been through
Host 3 10:31
This. I don't remember now. Now. We started the podcast not long after I started so I think we were doing good especially because that's called super, super stupid stout or whatever. And it probably coincides with the super stupid powers. Like we had a theme going on, we had to put stupid
Host 2 10:50
In the names. Yeah. You guys just described every nerd movie ever made a thank you engineer Bob love chat. So anyways, this is the first beer that we did a collaborative design on or recipe on and we were entering it into Saint Arnold's yearly contest.
Host 3 11:11
It's called the big, big batch brew bash.
Host 2 11:14
Yes. And so St. Charles is a craft brewery here in Houston. And it that year was an American stealth. And so we were like, we can burn Americans out. And we I've actually never heard of stout before. I don't know if you knew that at this point. No, I didn't. And because you had Yeah, I had. And so I'm like, I beat we I pulled up the style guide and I, we pulled up previous winners of this contest. And basically everything had to be over like AV winners over 12% ABV.
Host 3 11:44
Yeah, that's the whole big part of the big batch. Like, these are all like super beer. Yeah,
Host 2 11:49
But they don't have that in their contest rules, though. No, they don't. We just pulled up the, like winners. And we're like, Okay, we got to be over 12%. And it's got me American style.
Host 3 11:58
We saw last year's exam. Yeah.
Host 2 12:00
And basically, yeah. And so we came up with this recipe. And the funny thing is, if you look at this recipe, and you the especially the grain bill is be like yeah, told this person has no idea how to burst out.
Host 3 12:16
Yeah, the thing about this grain bill is like, it breaks so many rules.
Host 2 12:21
Yeah. So it's basically what a third the grain bill is what's called it's adjunct grains. Right. I think that's the term
Host 3 12:32
Yeah. So grains that are not your your just like Joe Schmo Jelly Bean based grains that make generic beer it like a third of it is the the extra stuff, which 30% of your entire recipe is a enormous amount.
Host 2 12:48
Usually, it's like, five percents. Yeah, somewhere in there. Yeah, I think it's called adjunct grains. Yeah, yeah. And this grainville is like 30 percents, and we brewed it's kind of in the what's considered the traditional English style way to brew, which is you brew about you when you mash which is like your mason making a tea with all the grains. When you mash it, your first draining of your tea off the grain. It's called the wort not tea, but when you drain it, that is called your first runnings and in traditional English style, your first runnings makes your stout and then you fill up your your, your grain back again with water, hot water and you mix it all up and then you get your second runnings off of it. So you get more sugar whole point is getting all your sugar out of the grain. And so, the traditional English style is your second runnings makes your Porter and then your your third runnings makes your bitter, okay. And so you have different levels, but your first one is going to have most sugar, your second one is going to have somewhere in the middle, and your third runnings has barely any sugar in it, because it's making like a 2%. Better, right beer. Now, most breweries moved away from that, because they found that ver varying your grain bill across different beers is actually beneficial. And so it's not as efficient. It's not as efficient as well. And so you basically what you do is you you mix all your runnings together to make a beer, and you make one beer out that so you use less grains and extract more sugar. So we did the old English song because we needed we needed the concentration of the first runnings to make this big, because basically, we calculated it out and we're like, the only way we're going to hit that number is to do the first runnings and just do as much as we can. Yeah, like ratchet every knob to 11. Yes. And so we had basically we took my mash tun which is the bay It's a cooler, it's a cooler, the biggest cooler I had. And we filled it up with like 30 pounds of grain and filled it all the way up with hot water. And then let that sit for an hour. And then we did all the runnings and all that stuff. And we didn't make a better but we ate a porter. Right. And it was actually my opinion, my favorite beer ever made. And it was spectacular. The problem with the porter though, is we can replicate the grain bill. So we had that written down here. But the hop, Bill, I guess, build hops, yeah. The hops, were just leftover hops that were in a jar in my fridge or freezer. And so it's like, we have no idea,
Host 3 15:47
No idea what they were, and ended up being one of the best beers we've ever made. Yeah. And it's just like, Oh, God, so you got five gallons of it. And that's it. Yeah, it was so good.
Host 2 15:58
Technically, I guess we could reverse engineer what was in that jar by going back in the last like, three years of notes. But yeah, whatever.
Host 3 16:09
So okay, one thing to note, the whole mashing and then pulling off the first runnings, basically, with this beer, it ended up just being like black tar that comes out of the mash tun. Because I mean, it's almost a syrup, because it has so much sugar in it. Yeah, like, almost to a sticky level. The thing about the grain bill that that most of the time when you're developing the recipe, something to keep in mind is that if you add all these adjuncts, and all these other things that are not your normal barley, or if they're highly modified barley, you end up really screwing with the pH of the wort. And when you're making that tea, the main mechanism that actually extracts the sugar is enzymes that are present within the grain itself. So different enzymes get activated at different temperatures, but they also get more or less efficient based off of the pH of the water effectively. And that's affected by the grain, which is affected by your recipe. Now, here's the thing with this beer, we have so many dark roasted like chocolate, black, patent malt, like all this stuff that just absolute makes this water just completely acidic beyond belief. And you would think that you'd have terrible efficiency, like the water is so acidic, that the enzymes are not going to efficiently convert to sugar. Nope, somehow, they like supercharge get the sugar out.
Host 2 17:39
It's amazing. It's like we kept when we calculated it out, because I, so what I would do is I will do my recipe in the calculator and all that stuff. So I get my calculated, and then I always will measure it. At the end, we exceeded expectation by like 10% on everything,
Host 3 17:57
Which is insane. Yeah, like I said earlier, we broke every rule. And on paper, this recipe should not work.
Host 2 18:04
And we unfortunately, we also broke a rule with the contest because it was supposed to be an American stout. And we chose an Australian hot Australian hop for our flavor hop because the bittering was Goldings because Goldings just it doesn't matter, right? You just want the Alpha content for this. But then we use glacier hops, which is an Australian hop, which is because I think we were looking at it and we're like, that looks like it'd be tasty, I think is our decision, right? Yeah, basically. And it's it's glacier is a American hot but it's grown. It's like a super hot that is like bread and so it has higher alpha content basically has more bitter oil. It's easiest way explain it but so it has more percentage so you can use less of it and to get the same flavor. But tastes just the same as a American out hop. So kind of laying that we lost. We lost on a technicality. We might not have won but we got eliminated because of a technicality.
Host 3 19:07
Yes. Yeah. They think those points on that regardless, when we got the score sheet from from this beer, it was like everything was like no technical issues. Everything is great about this beer. technicalities. The reason you got dinged
Host 2 19:21
Yeah. So why did I bring up the story? I don't know. Barker. Why did you bring up this? So Steven rebored this beer two months ago? Yeah. And brought a bottle or a couple bottles down actually.
Host 3 19:35
Yeah, so Parker now has a handful of bottles which was something this month monstrous. It needs some aging. Even though it's been aging for a few months in my closet. It needs a little bit more time but it's almost 100% there. It needs
Host 2 19:48
To sit in an A. It needs to sit in a Houston garage in September.
Host 3 19:56
Oh G for accelerated aging for accelerated a Jean. So So I calculated this one to be somewhere between 11 and 13% alcohol, which is maths, it's
Host 2 20:08
A big beer. It's not as big as, as the one we heard last time, but also last time we had my super cooler.
Host 3 20:17
Yeah. Okay. So in fact, I was making a joke about this earlier. What's funny about it is I followed the recipe to a tee. So all the ratios of all the grains are exactly the same. And I chose really close adjacent hops to what we had used previously. So in all regards, this is exactly the same beer, however, the alcohol content, and therefore the sugar content is slightly lower than the original one. And that is actually because my beer brewing system isn't physically large enough to hold enough grain to get that much sugar.
Host 2 20:51
Yeah, not just that, though, but I haven't found a lot of evidence for this yet. But when I switch to my new style brewery, which I have to show off after this podcast because you haven't seen it in person, I went to the standard, what I would call a, a
Host 3 21:11
Host 2 21:11
Tall, tall ratio, mash tun, which a lot of people were like, This is the best way to do it. I cannot get anywhere near the efficiency I had in my cooler.
Host 3 21:24
Okay. I think there's some evidence for that I've saw this was years ago, but I saw a paper that someone wrote where they chose, they tried different drain ports. They tried different shapes and ratios of length, the width, the height, kind of thing for for that. And rectangular coolers did better than cylindrical mashed yet.
Host 2 21:42
So I think I've seen and I've talked about this a bit, and I call it like Season Two of my Brig. I'm going to go back to a cooler, I'm going to I'm going to make it all like night hard plum.
Host 3 21:57
Plum, the cooler in because that cooler I was so usually you hit like 60% efficiency on extracting your sugar for like the style of brewing I do, I was getting 85 to 90% of that cooler. That's, that's nuts. And I think it's just the ratio, the best I have ever gotten is 72% in my system, and that's when like all the stars were aligned, and everything went beautifully that day. It's between, it's almost always guaranteed between I'm sorry, not 70 to 75% is the best I've ever gotten. But like if I ever screw up or I missed something, or I didn't crack my grain Well, I guarantee you it's that 75 drops to 70 or 68.
Host 2 22:42
Yeah, so I'm probably going to go back to having a cooler mash tone, and not resarch.
Host 3 22:52
Just hit it and let it
Host 2 22:55
Sit. I am going to I think I'm going to experiment with putting auto stirs in it. Just keep stirring it. I saw someone who put RC helicopter blades upside down with a big motor. Just spin it around, like interpret align it. And I don't know how it's gonna work in a rectangular setting. But I'm gonna try
Host 3 23:20
It. I would think that like if you made stainless steel paddles and put them on a low speed high torque motor, or like a paddle boat, like a paddle boat, and just a book, but instead of like paddling through it, you put them you put the paddles vertically down Sorge in it also spins like Yeah, yeah. Uh huh. I would think that that would get enough movement. Because I know that there's, there's, you can get efficiency increases by just stirring with
Host 2 23:47
A spoon. Yeah, just a big paddle works wonders,
Host 3 23:52
Right? And the large brewers, if you look at their mash tuns, oh, they're they're agitated constant agitation. Yeah.
Host 2 23:58
Well, because they're, they're looking at their bottom line. Right? They need they want 100%
Host 3 24:04
Right, right. Yeah. 100% minimum. Yeah.
Host 2 24:09
So yeah, it's it's amazing. Yeah, I switched his new brewery and I'm just like, underwhelmed, I guess, because how much effort I put into that brewery. And I'm like, This is not as good as my turkey burn like turkey fryer. Propane thing and like, a cooler I bought at Academy.
Host 3 24:28
Well, okay. You know, that actually brings up an interesting thing because like, Yeah, I mean, I caught a glance of your brewery.
Host 2 24:34
It is a post way it is way easier. Like when I designed it. The number one thing was make it easy to clean. It is super easy to clean though.
Host 3 24:43
So so that might be worth like taking the efficiency hit for the added benefit of loneliness. No,
Host 2 24:50
Wasn't worth it. And, yeah, I don't know. It just I think I need to combine the two Whew concepts. Yeah, make it eat make the brew kettle and the hot liquor tank easy to clean. And then the mash tun is a cooler that you can disconnect from the system quick disconnect fittings on it. Yeah, make it easy. Make it easy, and then you can just dump it over. Sure. Yeah.
Host 3 25:20
I mean, the evidence is there in terms of I've brewed with your cooler twice, I think. And I was it was it's another one that just blew my mind was like this shouldn't be happening. No shouldn't
Host 2 25:33
Because so at the bottom, it has one extra at the end, and just a stainless bazooka too, which is basically just a mesh tube that prevents the grain from going in. And then the other trick though, is you have to basically almost pulverize everything well, yeah, it's it's almost flour, almost flour. Yeah. With xOP people will like set their their grain Crusher to like credit card. I think I did half a credit card.
Host 3 26:01
I so I actually got my feeler gauges out. And I did like set mine to 18 Thau is where I have mine set. So half a credit card basically because the credit cards are brown third. Yeah. So I've found like that worked. But I also have to have my drill on like high torque low speed reading to get stuff.
Host 2 26:20
Yeah, I use my big seven amp drill. That grain.
Host 3 26:25
Yeah, yeah. My drug is hot going through five gallons. Yeah. So
Host 2 26:29
Anyways, this is even though you didn't hit the alcohol content or sugar. It tastes almost identical. It's
Host 3 26:36
It's pretty much there. Yeah, I mean, I think I think the flavor is basically exactly what we had before. It might have just slightly less kick.
Host 2 26:45
No, still got the warmth. So I would say if I can't tell the difference in those about 3% ABV difference, you can't taste it. I mean,
Host 3 26:55
Yeah, once once you get to a certain level like this is this is on par with some wines, you know, Oh, yeah. So it's a it's good. It tastes it tastes like chocolate coffee cherry. And really sweet.
Host 2 27:07
Yes. An engineer Bob says I need to add some RGB LED Christmas lights to my brew rig in season two. Oh, so I think Season Three was going to happen after I move out of this house though. So because it really the problem with it. It's one of those like, it's like so I live in my parents is old house. Okay, this is the house I grew up in. So I basically I moved around after afterwards but like I came back here and the problem is it's a lot of house and not enough garage.
Host 3 27:46
Now the garage is pretty big these garages Yeah, this is this is
Host 2 27:50
We're actually are in part of the garage. This is like the side room in the garage. That's like fully insulated and has air conditioner and stuff. So it's, it's really nice. Everything's nice. I want to like flip the square footage around. I want like 2000 square feet of garage. And like 1000 square feet maybe of house.
Host 3 28:12
A kitchen, a bathroom and a bedroom. Yeah.
Host 2 28:15
I mean, I don't use a lot of like, yeah, I use the kitchen, the bathroom and my bedroom in the house. That's got it's got like a dining room and living room. Three bedrooms and like, I don't use any of those. I feel like a barndominium would be perfect for you. Yeah, so I've been working on barndominium design, finding a piece of property to go move to so be here in Houston. But I Paul, I'm actually designing the floorplan, I'm putting in a floor drain like a trough where the brewery is going nice so that if I spill something, I just squeegee it into the drain. That's perfect. Yeah. I got that idea from my uncle. My uncle's brewery down in Alvin. Texas has a trough drain in front and you just like just put the hose right there. And so when you clean everything, everything just goes straight down. You don't have to worry about it. So
Host 3 29:08
I know this might seem a little bit gross, but I was talking to an engineer at at a previous job. And he was talking about designing his brewery because he brewed a bit back in the day. And his idea was to do something similar, but instead to put a urinal, but one of those urinals that goes all the way down to the floor. Oh, so it was like a multi use well, but he wasn't gonna put it in the actual brew room. But if you ever needed to dump something, he could just go to it.
Host 2 29:37
Gotcha. Yeah, now I'm gonna have it in rural is going to be you can only dump Bruce stuff in there. Okay, because it's gonna be the whole shop. Right? But I'm gonna I'm gonna put it up you're not gonna drop your motor oil or No, no, no, I
Host 1 29:49
Don't. Because that gets recycled, man. Yeah, but that's exactly what I'm saying. You wouldn't do that. I'm gonna
Host 2 29:55
Have other things or having like a utility sink. Yeah, a proper because right now I use the kitchen sink as a utility sink. Don't tell my mom
Host 3 30:05
I've been looking to install a utility sink in my basement and luckily, I suppose you haven't yet. Well, you know, the funny thing is like it's just worked out that I haven't needed it yet. But like, I'm also realizing if I hadn't, I would have already used it. And I've looked up in the ceiling and right where I want to put it. There's hot and cold copper pipes, right there. Oh, perfect. So just like cut sweat new pipes on drop them down. It's just
Host 2 30:30
Having hot water for utility sink is awesome. Oh, yeah.
Host 3 30:34
I just I wish I wish I had enough room to do a double utility sink. Two sides, but I think I can get away with one. I mean, I've gotten away with zero. So
Host 2 30:44
Yeah. So engineer Bob asks is my uncle was a sailor, because I think every boat has a scupper is a skipper? What's a skipper?
Host 3 30:54
I never heard of us copper.
Host 2 30:57
And wonder if that's like a floor troth drain. But no, he would probably be the opposite of what a sailor would be. It'd be really fun to I think the Maghreb engineer podcast is the wrong spot for someone like my uncle to be on the podcast. Oh, hey, go
Host 3 31:17
Scupper. A hole in the ship side to carry water overboard from the deck. Okay. Yeah. Very. They have names for everything. I call the hole in the side of the ship. It's a drain.
Host 2 31:32
So, well, engineer logical engineers have weird names for other things, too. So
Host 3 31:38
Yeah, and we're all fancy. We use j for imaginary numbers. But yeah, because somebody back in time was like I is current.
Host 2 31:47
That's right. Oh, my gosh, I completely forgot about that. Yeah, we were all the heavier guys I used. Yeah, it's been a long time since I've actually written down a formula. We're using variables, because now I just write down like, oh, yeah, for some reason, V equals IR or something like that. You're totally right here. I just weren't even thinking about it.
Host 3 32:06
Yeah, there was there was some kind of like, really goofy elitism on my school where it's like, well, we use J. I think mathematicians use j for unit vectors, don't they? too. So it's also it also gets even more confusing when Yeah,
Host 2 32:21
So what unit was a then? Why? Because? Is there a reason why amperage was I? Hmm, that's the interesting thing about now what's the who came I think, who discovered or named amperage? Tory ampere?
Host 3 32:42
You don't remember the person's name. So? Yeah, ampere. That's, that's, that's it. But I remember using the capital letter A to represent the gain of a system. Capital A Yeah, yeah. And we wouldn't use G we'd use capital A for it. I don't remember why I want to Google. If you get good, like simulation software, a lot of simulation software will use the capital letter A Ah,
Host 2 33:09
So if you Google, this might be because of me. But if you type in Why is amps The first thing is Why is amp symbol
Host 3 33:18
Is nice. Yeah. What does it say?
Host 2 33:22
The eye symbol was used by Andre ampere. So it just because the person who discovered or because he just did it, he just did it. I think that's what it was.
Host 3 33:33
He just did it and no one was willing to change. Because we could if that's the logic, we could have used J for current and done I like everyone else but nope. Some of these things get stuck and that's that's just it.
Host 2 33:50
I'm making sure it's just because
Host 3 33:53
But but you see if I was if I was to write out a formula for a transfer function that includes reactive components, and I had to write i omega c or i omega L or whatever like that just wouldn't have
Host 2 34:08
You already. How do you pronounce so Chris in chat says blame the French because of intense seat are it 10 sight do current which is the intensity of current intensity of current Yeah, so I is that is what amperages huh? Yeah, so problem salt. Hod.
Host 3 34:40
Having to go check on something real quick. Intensity, do curl. Something like that. I don't know. My French is terrible. That dogs doing something.
Host 2 34:54
My dad's like, I'm going to the grocery store and I'm like, we're recording podcast. You want to tell me you need thing.
Host 3 35:02
Oh, whatever. We're having a good time.
Host 2 35:05
So that's so I can cut it out. For Josh. Yeah, so that totally makes sense intensity current. It's always it's always something like that. Or it's Latin.
Host 3 35:18
Yeah, yeah, for sure. Although like it's i for intensity, but yet we still the unit is amperage, which is his last name. So both of these the most both of these things are still arbitrary.
Host 2 35:30
Yes, it's so Yeah, cuz. Yeah, cuz you couldn't be? Well, it's just like, because you've met on your multimeter. Could you imagine it being intensity of current and so just amperage?
Host 3 35:43
Oh, gosh, yeah. intensities. Lenses, the amount of okay, here's, here's the one. I'm trying to I'm trying my
Host 2 35:50
It'd be IOC. It says your current.
Host 3 35:54
I wouldn't want to write IOC every single time. Okay, I'm going to totally off the cuff here. But maybe someone can explain this to me. Gosh, okay, Maxwell's equations. Remember Maxwell's equations for that define electromagnetism and light, basically, right? Yeah, Bob Barker is like I don't want to remember. So, gosh, what's the guy's name? Somebody came around. And so Maxwell's equations was like, one of the there's four different equations for Maxwell's equations. And one of them was something equals something times or something crossed something equals something bah, bah, bah. Well, somebody came around and was like, in this one situation. If you set this equal to zero, it tells you something and then called it his equation by just setting it equal to zero. And I'm like, That's bullshit. Like,
Host 2 36:50
You could call that like a theorem. Can you call that like a theorem?
Host 3 36:54
I mean, like, okay, so if you have an equation, and that equation encompasses all values, then how could you say if it's this value, it's my equation. But like, that seems garbage to me. So I don't know if I can't even remember what it's called. But like, it's literally somebody's name is like, it's not Maxwell's equations anymore. If you set it equal to zero, it's called someone else's equation. And I don't want to discount somebody's work because they probably put a gazillion dollars to work.
Host 2 37:23
Is it gos? Is magnetic law?
Host 3 37:25
I don't maybe I don't think so.
Host 2 37:29
There is one zero that is present in Maxwell's equations, which shows up in Goss's magnetic law,
Host 3 37:34
Is that we I remember joking about it in in college. Yeah, we were all like
Host 2 37:42
It's upside down delta times b equals zero, wherever that means. I love that upside down delta V.
Host 3 37:50
I think all of that is wrong. That is, isn't that the divergence of the magnetic field is equal to zero? It's?
Host 2 38:05
Yeah, it's Webers meter cubed.
Host 3 38:11
All of this stuff is not
Host 2 38:12
Not line. magnetic charges measured in Weber's? Yeah.
Host 1 38:19
That's the fun. That's the fun part about Maxwell's equations is I know, like, on a fundamental level, I know that they are so unbelievably important, but they're so like, not usable by my everyday life, that you're just like, what?
Host 2 38:33
So what is the upside down delta, then? That's,
Host 3 38:37
I swear this divergence, isn't it?
Host 2 38:39
Is it divergence?
Host 3 38:40
It could be? Yeah. Give me one second. I'm looking at. Now we're going deep here. We haven't even started the podcast.
Host 2 38:46
We're supposed talking about bench. I was going to segue when I mentioned multimeters.
Host 3 38:52
Yeah, okay. I was right. Okay. in vector calculus. divergence is a vector operator that operates on a vector field, producing a scalar field given the quantity of the vector field source at each point. So it's like field magnitude, I don't know long since I've done it's at field magnitude at each point.
Host 2 39:17
I think that's, that's like it starts rolling down the like, spherical cow. Yeah, where you are, if you surround it with a sphere, because you're measuring like, basically, everywhere. The cow field cow field. That's totally me. I
Host 3 39:37
Think, I think the best the best technological cow thing I've ever seen, is the image and i've showed this to Parker so many times because he knows what he's talking about. But there's a picture that shows the aerodynamics of a cow versus the aerodynamics of a Jeep, and a cow is more
Host 2 39:54
Aerodynamic than a Jeep. Now. To the credit, the Jeep had no roof and the doors off but still
Host 3 40:01
Well, but that's like, that's how people want to drive Jeeps. Yeah. Yeah. That's so good. Yeah. finite element analysis on cat.
Host 2 40:12
Yeah. So I, I was going to segue into our topic when I mentioned multimeters. So our topic this week, the real topic 43 minutes in, should we just say this for next month?
Host 3 40:27
We really 43 minutes. Yeah. Why don't we just save the why don't we just like, keep keep on this train for the rest of the time? Yeah, yeah. So sorry, everyone, but also you're welcome.
Host 2 40:38
Where we talked about Maxwell's equations a little bit, which probably made everyone like Scream now. Well, now. Okay. So chit chat. I now I'm really like bothered? Is it Poissons equation? That seems wrong? You talk about the one that's equal to zero?
Host 3 40:53
Yeah. Because like, okay, so, so Okay, so what if I said, if v is equal to IR, if IR is equal to zero, I want everyone to call that Craig's equation. Which if IR is equal to zero, that means there's no current. So if you have a resistor with no current on it, you're satisfying Craig's equation?
Host 2 41:13
Well, there's gonna be some more was there? Is there a fundamental thing it creates? I would say, it could be like a proof. I know no. Proof after yourself. I believe you're right on that. You could be like a Maxwell equation equals zero. And then you have a proof that explains how it's equal to zero,
Host 3 41:35
I think. Yeah, I think above and beyond that. I think you're totally right. I think perhaps what it was is at the condition where it is equal to zero, there's something it will make us funky but like electromagnetic waves, so yes, it's every ounce of it. Yeah. Yeah. But I think at that, at that condition, things were there was there was some other fundamental thing that was explored. And because of that, it was granted. You know,
Host 2 42:00
Okay, yeah. It's not just your it was equal to zero, there's something else behind it, which is
Host 3 42:07
We did joke about that a lot back in college, because it's like, Wait, this is all it takes. You don't have to actually discover anything. I'm being mean, something probably did actually happen.
Host 2 42:20
Your phone that you're, you're looking to stuff up on probably uses one of these, this equation we're talking about,
Host 3 42:27
You know, okay, so this equals zero, this, this was actually really fun, too. I talked to a,
Host 1 42:33
I talked to a PhD student when I was back in college. In fact, he was a roommate of one of my buddies. And we were, we were chatting with him about fundamental laws. And he was like, so you know, Ohms law, v is equal to IR, it's great. It's what everyone in this entire electrical engineering department like bases their entire life off of, and he's like, it becomes false. At high frequencies.
Host 2 42:57
You have to like, oh, yeah, it's called impedance.
Host 1 43:00
We'll know what I mean. Like it? Yes. But it's also like, it's not particularly reliable. And with what he was working on, he's like, we don't really even know what happens if we just try things and see what the result
Host 2 43:14
Is he curse and chat is kind of same thing. Goss's law,
Host 3 43:18
Is it Gauss? It must be the the divergence of be, wait, okay, so we'll wait. Doesn't that mean,
Host 2 43:28
There's also marae. Spiegel, who's See, stated explicitly that the proportional to the charge density, therefore zero, that doesn't make any sense that actual equations
Host 3 43:43
Are wack, dude. Okay, so, so I think, okay, it's been a long time
Host 2 43:47
Since I've looked at them. The divergence
Host 1 43:49
Of B, the B field, basically, correct me if I'm wrong here, but I think doesn't that mean that we, there's not magnetic monopoles? In other words, there's not places in space that just is a North field of a magnet. And I think if by saying the divergence of B is equal to zero, is saying that every magnet is going to have north and south. Yeah, it's all equal to zero if you encompass it all encompassing inside of our cow field. Yeah, right. It's a row. Every cows got a front end and a back end and like, it's all equal to zero if you as long as you encompass the entire cow.
Host 2 44:28
Yeah, yeah. We're, I'm pretty sure it's got his law, which is it's a it's basically the, the, I guess they say that about is if you haven't been netic fueled, and you encompass the entire magnetic field, it's gonna be zero
Host 1 44:43
Every every field line that exits as a what is it an area that encompasses it has to have a field line that enters it at some other point, right? It's all equals zero.
Host 3 44:55
Yeah, right. Right. Right, right, right. Oh, man, we're getting into like
Host 2 44:59
Gum, you can think about as it kerchiefs. What's the amperage node law?
Host 3 45:07
Current law, current care costs current current law? Yeah, yeah. Did they drill that into you back and go?
Host 2 45:14
That was my first year? Yeah. Yeah, that was included the all our circuit and original circuit analysis, which is like, you know, you're learning Okun's law, that kerchiefs law, and that kind of stuff was in there, too.
Host 3 45:25
You know, okay, so I remember so many homework assignments and exam questions that weren't like, you know, nodes of resistors, and batteries and all kinds of stuff. And you had to like define each node and you had to find current it was going out or into, and then I
Host 2 45:40
Think, on because it was like a whole semester. Okay. Yeah. On the fundamentals, V equals IR Ohms law and its derivatives are like the most important, you will learn that there and a bazillion times. But when it talks about kerchiefs, all is like equally as important. Yeah, whereas
Host 3 46:02
The volt voltage and current law, yeah.
Host 2 46:04
Whereas looking back was mainly the current law, or I would say, is looking back on it. All that you'd have to say is, if current flow somewhere, it's got to come back out somewhere.
Host 3 46:14
Yeah. And it's got to be equal. And the pressure in the pipe is the same everywhere along the pipe.
Host 2 46:20
That is actually untrue. But
Host 3 46:24
It's untrue. If there's some impedance, right? Well, if the pipe has impedance along the line along the line, that's the problem. That's that's the problem. But at fundamental level, you can say, a fundamental
Host 2 46:35
Well, and that thing is at a circuit, small enough circuit level, it's true as well, right? No, small enough current level, all of it, whereas when we, when you get older, you start realizing, you start realizing that this gradients, the ground plane.
Host 3 46:56
Yeah, yeah. Because if you start if you want, we've said this a bunch of times, if you just create your, your, your grand plan, like a giant bucket of zeros, that you can just pick zeroes out of, you're gonna get in trouble.
Host 2 47:08
I do that on most of my big designs, though. But again, I'm doing low speed, you know, and low current low current stuff. So it's not too big a deal. And I always separate high current out because I know that's gonna mess stuff up. So I'm like, Okay, I'm talking about the Pinball Controller right here. Because it's like, that's probably the most advanced system I've ever designed. And it works really good. Because you separate it out high current, you know, that's going to mess stuff up. So you make sure that's a way and all the low current stuff, you're like, Well, I'm going to have a lot of capacitance and decouple the snot out of everything. And that way, I make sure ground is ground and 3.3 volts is 3.3 volts wherever I needed. Yeah. And you actually measure it out when you're powering it up and using it. And that's true. Now, again, it's it's really when you start getting the mix system stuff that it doesn't it falls apart or like a bad design. I guess, too.
Host 3 47:59
Yeah, you have to start thinking about it differently. Right. Yeah. And that comes into like, I've had so many arguments. If you should have split ground planes, separate ground planes, or combined ground planes for system design. And I've there's good arguments in every camp. Yeah. And there's and there's plenty of designs that you could look at and be like, well, it's successful. And they did it that way.
Host 2 48:21
No, no, it just depends. Because like, oh, we had the whole podcast talking about different grounding techniques. We had like, we called the Star, star star grounding, and there was a plunge in. Oh, plane and plunge plane and plunge, which is the technique I usually use but on the like my pinball says it's both plunge and plane and plunge is the low current digital side. And then the high current power side is star.
Host 3 48:54
Yeah, or galaxy. Remember galaxy? Oh, yeah. Galaxy was fun. Yeah. It's hybrid star,
Host 2 49:00
I guess. Yeah. Hybrid star. I guess you if you had separate ground planes, you could say it's technically galaxy. I'd call it nebula though.
Host 3 49:10
Super Cluster, Super Cluster. I love it. And you can get away with playing and plunge with high current, you just you're not going to have one via you're going to have via patches and stuff. Yeah, a lot
Host 2 49:21
Of that. And usually the because Oh, man there was there's a very there's a very interesting video I haven't watched yet. But is the claim that current doesn't flow through your board.
Host 3 49:37
Where everything's what static?
Host 2 49:39
Now it's very interesting. I think someone posted in our Slack channel. I just haven't gotten around to watching it yet.
Host 3 49:44
I mean, that seems a little ridiculous on its face. Well, it
Host 2 49:47
Goes back to what we're just talking about with Gauss law where you have exiting magnetic fields and then entering magnetic fields. And then magnetic fields is actually what's causing the electrons to move. I think I think that's what that's going on.
Host 3 50:00
Are you saying like the net total is zero?
Host 2 50:04
No, no, I'm just going out with the cause, like, when you have a, we've talked about this before, when you have a giant plane, but you have a trace that the current is flowing through over it. The current return current actually flows like under the trace through the plane. It doesn't spread out over the whole plane.
Host 3 50:26
It does, but it depends on frequency
Host 2 50:29
Dependent frequency, we're talking about just low frequency.
Host 3 50:32
If it is low frequency, it will spread across the plane. Not fully, though. No, it is, look, it's so localized, but it's a gradient. It's like it's like a giant like Cloud. Yeah, that flows. But as the frequency increases, that cloud narrow begins to be the same size as the trace above it.
Host 2 50:50
And so I haven't watched this video yet. So I don't want to I guess I shouldn't have brought it up, because I don't watch it yet. But I'm planning on it. And it's it's a to that effect that the current isn't actually flown to your board. We'll see how much clickbait that is. Let me see if I can find it real quick.
Host 3 51:10
I'm now I'm curious to see get you to listen to this, because it's like, I don't see how that claim could be made. Unless they're talking about, like, you feed your circuit with whatever power whatever current goes into it. And then obviously, I don't even know that like, I mean, that gets distributed and flows to whatever. I guess the only way you can make that kind of claim is if you're talking about like, the total net for like AC current, like the argument we were having about AC versus DC the other day,
Host 2 51:41
I hear this. So if the amp hour retweeted or tweeted about it, so it must be true. Oh, it has to be true. It's so it's energy doesn't flow in wires.
Host 3 51:51
Well, okay, well, that's different to say the word energy versus current. You're right.
Host 2 51:55
You're right. See,
Host 3 51:57
I haven't seen this, but no, you're all good. Yeah.
Host 2 51:59
So my I'm gonna watch this. What who made this? Oh, that's Veritasium. Yeah. Oh, oh, that's a really good one. Yeah,
Host 3 52:07
Those are usually they have a high production value. So energy doesn't flow in wires. What does that even mean? Yes.
Host 2 52:15
So all I remember is seeing the flow in blah, blah, blah. But then like, I remember seeing, like, you look at the thumbnail, it's a bunch of basically the EM waves coming off the wire, your right hand rule?
Host 3 52:31
Oh, we call it we call it the Aggie rule at Texas a&m.
Host 1 52:35
You do? Okay, so I went to a store just last night. Because I'm back in town. I was visiting a buddy. So I went to the store to pick up some before went over to his house. And I put down my card and paid for it. And the guy saw my ring on my hand and he said thanks a gig and when I left the store and I just gave him the biggest grin and a thumbs up on the way out it was it was perfect. It was it was what I expect from Texas.
Host 2 53:06
Host 3 53:08
Yeah, yeah, it's pretty bad. It's cringy isn't it? Yeah, real cringe. But, but it's funny because it just fits.
Host 2 53:16
No, it's perfect. Actually. Yeah, totally. Y'all do that?
Host 3 53:21
We would, yeah, well, that's okay. So that's a great example of one of the professors being like, I'm gonna really get to connect with these kids. Totally. We had fun. We had fun making fun of our professors. That's for sure.
Host 2 53:38
My Okay, so when I just lost story than what in the podcast, so about 56 minutes of just stories at this point. When I was a petroleum engineer, so my first year and a half, I was actually training to be a petroleum engineer. Because when you're in school, you're not an engineer, yet. You're training to be one. Or learning to be one I guess, if you want to use learning. And there's a bar right next to engineering part of campus. You know, we were talking about how engineers are like, in the corner somewhere that UT it's that way. Oh, yeah, there's a there's a corner of campus that is where the engineers and then they put the math people in between as a buffer a buffer.
Host 3 54:29
The rest of the people like math people are weird, but engineers like Whoa, yeah,
Host 2 54:33
Well, the practical math. stuff gets really it's when they start fudging the numbers to make it practical right.
Host 3 54:42
So so you what you're telling me is they were next to the business people that's what you're
Host 2 54:45
That's a little farther down. That's when you start lying about numbers,
Host 3 54:49
Host 2 54:57
And so there was a there's a bar are called posse east. If you're in Austin, go to posseses. Right off campus, North Kent, North East Campus, really cool little dive bar. They still sell pitchers of beer and that kind of stuff. And when we would go, an hour's worth, I would always ride my bike next to it, because that's where I've come into campus. And I would always see my petroleum engineering professors there. And then five minutes later, they're in the class. Oh, man, one dude couldn't stand up at time.
Host 3 55:34
Sounds like petroleum engineering does. Yeah.
Host 2 55:39
I was gonna be Petroleum Engineering until I took my first proper geology class. You're like, Nope, I took a class called sedimentary rocks. And this is you tease kind of a weird call it the biggest difference between UT and like a&m in terms of engineering colleges is a&m has like, like classes for engineers, and they group them all together, which is great for for, because everyone in your class knows where you're coming from that kind stuff. Whereas in UT, it's the opposite, which is like, you take math with old math people, I was taking sedimentary rocks with geologists. And I was the only engineer in that class. And, and they were all into it. I could not figure out how to get excited about that class. It was that bad. And I was wasn't bad. I just in that I, when I was kid, I collected rocks at a rock collection, different kinds of rocks. And I was like, Yeah, it'd be like that. No, no, no, no, no, it's not like that at all. And I was in that class for about two months. And I'm like, You know what, I'm doing this kind of like electronic things on the side, I want to switch electronic and let's go engineering. And, and that was that I walked into the, the office over at engineering college, and I'm like, I want to transfer and you know, like, what, I was the only person that semester transferred in.
Host 3 57:14
Yo, and so
Host 2 57:15
I got approved right away, because usually, they don't let people change easily. Because, you know, they don't want somebody to go into easier in quotes, engineering college and then transfer in because you have to, like, you have UTL. No. Other college. So you have to apply to that specific engineering college. Yeah, I think that's normal.
Host 3 57:37
When I switched majors, from aerospace to electrical, I had to have an interview with both the head of a wow, of electrical and aerospace to be able to do
Host 2 57:48
It. Oh, they just said, yeah, come on, because I was the only
Host 3 57:52
I had to make specific times for both of them. And it was funny, because like, but like, that was like school policy to do that. But like, I spent maybe five minutes with both like the aerospace guy was like, Why do you want to leave? I was like, I like electrical. And the electrical guy was like, Why the hell would you want to do electrical? I was like, because that's what I do for fun. And he's like, Okay, fine. Yeah.
Host 2 58:14
Yeah. That was that was when I had when I entered that was like, Why do you want this like, well, I'm doing on the side. And petroleum is kind of boring. I didn't have a exit interview, I guess with petroleum engineering.
Host 3 58:26
I think they probably did. In that situation, because I was a freshman. Just making sure that you're not jumping ship.
Host 2 58:33
Oh, yeah. Cuz I was I was technically a junior. No, I was end of my sophomore year. Okay. That's when I switched. And then it was a lot of fun. So we should end this podcast.
Host 3 58:45
I think so. Yeah. We're at an hour. Just a tad. All right. Well, that was the macro fab engineering podcast. We were your host, Stephen Craig
Host 1 58:55
Host 3 58:56
Parker Dolman. Take it easy later.
Transcribed by https://otter.ai