- Cheers to all of our fellow engineers on National Engineers Week!
- We would love to hear from our listeners. Tell us what you think, your current projects, any topics you would like us to cover, or just say “hello”. To reach us follow us on Twitter @MacroFab or send us an email at email@example.com.
- Scott wrote in earlier in the week. Gives the podcast two thumbs up. Thanks, Scott!
- Stephen talks about how he got started in Audio Amplifiers and how it led to him becoming an electrical engineer.
- Built his first Tube Amplifier 12 years ago and it still works. See Figure 1.
- Dilbert – The Knack
- The greatest resistor in the world doesn’t fit inside the My200 Pick and Place. Will be remade with 0201 10K resistors.
- The Jeep Radio Hack made it to Hack A Day. Check it out!
- Rapid-Fire Opinion (RFO)
- Down and Dirty with Contact Cleaners – on Hack a Day
- TI HDC1080 temperature/humidity sensor
- Steve wrote in to let us know about this neat chip.
- Relative Humidity Accuracy ±2%
- Temperature Accuracy ±0.2°C
- What sets this device apart from other humidity/temperature sensors is there are no analog readings involved. The output of the device is an I2C interface.
- Is owning a 3D printer worth it?
- Parker: If you know CAD, Yes. You treat it like another tool in your toolbox.
- Stephen: Making just silly plastic toys is not worth the expense of a 3D printer.
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 00:10
Hello and welcome to the macro fab engineering podcast. This is episode 56. We are your hosts Parker
Host 3 00:16
DOMA and Steven Craig. So this week is National Engineers Week. Whoo, we
Host 1 00:22
Got a holiday.
Host 3 00:23
Do you know what that is? No, neither do I
Host 1 00:27
Get the week off either.
Host 3 00:28
So yeah, I guess I guess it's it's some week where we are supposed to be celebrated in some way, shape or form. So yay for engineering. Whoo. Go. You'll work long hours
Host 2 00:39
Go. Yeah, actually, this week has been pretty rough in terms of hours wise.
Host 3 00:44
So to all the engineers out there, we tip our hats to you and raise
Host 2 00:47
A beer. If you're listening to us. Not at work. Take a drink pirate. That's tasty. Okay, so this is our self promotion little segment, I guess. Yep. We would love to hear from our listeners, tell us what you think your current projects, any topics you'd like us to cover? Or just say hello, which actually some people do. Yeah. You can reach us on Twitter at macro fab or send us an email at podcast at macro fab.com. So last week, I think it was right after the podcast thing was on Friday afternoon or Saturday, Scott Vale sent us an email, he says or he that says he writes. Hey guys, my name's Scott. I've listened to every Mac fad podcast since episode one. And it's by far the best engineering podcast out and I listened to all the other ones. He lists all our quote unquote, competitors, I guess. You guys do a perfect mix of technical information and current events. I wouldn't change a thing. Keep up the good work. PS. I think it'd be a good episode to hear more on Stephens history of working on guitar amps. Since I am an I work in the audio gear world as well.
Host 3 02:05
So thanks for Thanks for writing in Scott. And we were putting this here not to just have it be like super self promotion of the podcast. Really, it's more to answer the question about
Host 2 02:16
The PS but yeah, the PS though the first part is very nice. Yeah.
Host 3 02:19
Thank you. Thank you. Yeah. Thanks so much. And I'm glad that you really like it. i We try to make you like it.
Host 2 02:26
That's part of our job. So yeah. So Stephen, what is your history of amplifiers? And how did you get into that kind of stuff? Okay,
Host 3 02:34
So I'm gonna do my absolute best to not go on forever on this because I probably could. So firstly, minutes. Yeah. Right. So so first of all, the reason why I'm even an engineer is because of guitar amps. So I have that engineers curse of having to know how everything works and having to take things apart and
Host 2 02:56
The Dilbert comic that you don't have, they had a Dilbert cartoon. Yeah, they have a video called the neck. Yeah. And so it's like little Dilbert is like taking apart a radio, like, inside like a doctor's office and like this bomb. You're gonna say inside the womb? No, no, no, no. No part of radio and like, I think there's actually like a doctor came into the house or something. And the, the mom is like, what is wrong with my son? And the doctors? Like, sit down, ma'am. Your son has the knack. She's like, he's cursed to be an engineer, engineer for life. Well, okay, so
Host 3 03:37
I guess in some ways, we both kind of have that. Yes. You sort of have to be a little messed up in the head to be an engineer. So, so Okay, debate. Back in high school. I was in like an emo punk rock band kind of thing.
Host 1 03:53
Did you have you paint your fingernails? No, no, I
Host 3 03:56
Never duds? No, I did the I did the whole like, generally tight jeans and like shirts with ironic phrases on them and trucker hats and things like that. It was a bad.
Host 2 04:07
That's a different kind of email. I'm thinking the emails at my school were what I just described.
Host 3 04:12
Okay, well, you see, we called that scene. Regardless, that's, that's that's way long ago. But I was in a band and and I was I was the lead guitarist and of course, like I lusted after, like these big guitar amps out there. And I saved up a bunch of money to Marshall. 1,000x. Yeah. Well, it wasn't Marshall. I wanted a Marshall JCM 2000 and has a longer name than I just said. I wanted some help from my parents to get this amp and they would not let me have it. Or they wouldn't give me cash. They were like, you have an amp. You don't need to be louder. You don't need more of
Host 1 04:47
This crap. Mom. Dad, you don't understand. Yeah,
Host 3 04:50
It was it was almost like that. But here's the thing. I thought I would get the best of my parents because I knew they were suckers for educational crap. So I came back and I said, Okay, you won't help me buy one off the shelf. But if I figure out how to make one, will you help fund that project? And they said, Sure, you you make one from the ground up, and we'll help you do it. So I spent six
Host 1 05:14
Months don't like a kilowatt amp. Yeah.
Host 3 05:18
I spent six months researching. I mean, it was like, non stop. I delved way into the world of amps.
Host 2 05:27
And this is in this is in the early 2000s, then right? This is 2004 to the on the internet with a piece of crap. Yeah,
Host 3 05:35
There really, it wasn't as as nice as it was today. So searching for these things was you had to do some, like legit searching and digging.
Host 2 05:43
It's, that's actually interesting thing about the internet is around for some reason around 2006. Like when I start searching for like, I need to figure out how to do something. Yeah. 2000 like anything before 2006 doesn't really exist in Google search history.
Host 3 05:59
Yeah. It's it's weird. Yeah. The internet was was was pretty weird back then. Yeah. So the thing was, I had worked on circuits before I'd actually even built some guitar pedals before, but I didn't know anything about how it worked. I just followed a like a diagram, and hoped that it worked. And if it didn't, I was like, Well, okay, it's crap now. But I ended up finding an amp that I wanted to build. And it did what I was kind of looking for. It wasn't the big beast of the JCM 2000. But it was that amp that I wanted, and I ended up getting a bill of materials purchasing it all and I built
Host 2 06:38
Up on purchasing it. Yeah. Did they give you did your parents give you a budget? Or did you just say, I need this amount of money?
Host 3 06:46
I, I put in some of my cash. And then I said, Hey, I need a little bit of help, you know, so I don't remember how much it was. It really wasn't much. I think I needed like 100 bucks for my phone.
Host 1 06:58
And where did you get the parts back then back then
Host 3 07:02
I believe I got the numbers. So I had I had actually already ordered stuff from Mouser. So I got some stuff from Mouser. And I got some other stuff from a place called Mojo. mojotone, which they still exist. And they did this guitar Mouser had a web interface. Yeah, they did. And it was still good back then. It was awesome. We've talked about now they're being killer. So yeah, no, so So I got all the parts in. And I didn't follow the schematic. I literally just had a picture, I had a piece of paper with a picture on it. And it just showed where everything goes. And it had a bunch of different color wires on it. And it's just, if you hook it up like that picture then it should work. Lo and behold, I built the entire thing. It took me like two months, because I was really careful about it. turned it on first time I turned on fire it up and and went to town.
Host 2 07:55
Did you blow your door off? First time you turn it on? I was
Host 3 07:59
I turned it on with a yardstick because I was so scared of it. I didn't know what it was gonna do. But not turned on with a yardstick. And I remember playing it and sort of not liking it.
Host 2 08:11
So it wasn't like Back to the Future. It's like 40 knobs turning and then he strums and bone blows himself across.
Host 3 08:19
When I graduated high school, you know how there's a lot of those people who are like most likely to succeed, and most likely to this or that I got most likely to build the amp from Back to the Future. Yeah. So I built that amp. And I was like, I love this. It was so much fun. It was amazing. And at that point, I was like, I've got to go learn how to how to do this for legit.
Host 2 08:41
So that was the best $100 Your parents ever spent basically.
Host 3 08:45
Well, it turned into $80,000 worth of school. So the thing is, I thought that I would best them by getting an amp out of like, you know, playing their game. And it ended up changing the way I wanted to do things in my life. That's cool. Yeah, it worked out. So effectively, I went to Texas a&m, and I got my electrical engineering degree because I could build an app, but I had no clue how it worked. And that bothered me. I had to know why it worked. And ANM taught me zero about how the app works, actually.
Host 2 09:18
And you have a story about a professor and tubes, don't you?
Host 3 09:22
Yeah, yeah. Well, okay, so of course, like, everything I've learned about about amps, other than just like, you know, general electronics. I had to teach myself because nobody knows tube stuff. And when it comes to audio amplification, and so much of it is old hat that they don't really teach it they're like there's so much information you can just go learn it yourself. And and I remember my senior year at college, I told one of my professors, I want to go make tube amps. And she literally laughed in my face like straight to my face. It was it was almost comical, and I was like oh, it made me burn me up. I'm gonna do
Host 2 10:01
That's the thing is you actually wanted to go and build physical things. Yeah. Which they don't teach you at all in college and move. Like you do labs and stuff, but they don't like. I've talked like at UT. I took like the only class that we actually built circuit boards in the undergrads. Yeah. And like undergrads don't know how to build circuit boards.
Host 3 10:27
I had many classes where where undergrads didn't, couldn't hook up a breadboard. I mean, there were there was people failing breadboard at senior level, because they don't, electronics is less about like components anymore. It's so much like at a&m, there were so many, there was only really like one track that was in your
Host 2 10:47
Voltage, the electrons filled the holes, and allow the current to flow through the MOSFET. Everyone writes that down? Yeah, oh, yeah, I'm gonna have
Host 3 10:57
To remember this for the exam,
Host 2 10:59
Instead of instead of the most important thing is, look at the volt gate threshold chart, figure out the voltage that you can apply to the gate will actually turn on that MOSFET as much as you
Host 3 11:09
Need, right? And then go and frickin matters. But then you go and you try to put those those values into Mouser and find a fit that will work. And there's not one that will work. So you just kind of like that one, that one's gonna work. And you pick that and it works. And it works, or doesn't. That's real engineering. Yeah. So, so I graduated, and went off and got a job doing some stuff that was pretty much signal processing, and amplifier stuff. I worked there for four years until I decided to leave and start my own business doing Craig amplification. And at Craig amps, I built amps, I sold amps, I fixed a bunch of amps, I ended up starting a big repair center, which I serviced most of the guitar centers in Houston, and a handful of other music stores. And I did that for a while until I didn't like doing it anymore. Which was an interesting turn of events, because it was like my lifelong goal to go and like, make amps and make this big, big ordeal out of it and stuff. And
Host 2 12:12
Well, I don't think it was that it was just you were fixing stuff more than building new stuff.
Host 3 12:18
That was what yeah, that was one of the big things. Okay, so So I started this this repair shop. And one of the things I pride I took pride in was the fact that nobody else in in Houston was taking in like keyboards or PDAs, or mixers or things because they were they were just too hard to fix. And I was really proud of the fact that nothing left my shop, not working nothing bringing back twice. Well, no, no, some broken, stuff came back because of X, X or Y reason. But but it was it was more like, if you brought something to my shop, you were either going to get it fixed, or you didn't want it fixed at all. I could fix anything. That was my, I told people that and I did I fixed every keyboard that came in every mixer. And I because I had an electrical engineering background, I would go down and fix transistor level problems on keyboards, which most people would just you need a new $500 PCB swap, you know, and I was I was cheaper, I was faster, and I could fix anything. And what ended up happening is I just didn't like the work. After a while dealing with musicians is great. They're wonderful people, but it's just difficult when it comes to getting paid. Yeah, like the money aspect is is tough. Remember, you don't have to be political on the show. Right? Right. I love musicians, and I deal with them every day. And I'm one myself, but But ya know that that just that just suck the fun out of it. And so the thing is, I still run Craig amplification, I still have the business, I still have the DBA. And I still do a bunch of work with musicians. It's just I don't take in all the work. You can choose. Yeah, I pick and choose. And I work with musicians who are really like, they, they know what they're looking for. They're, they're willing to invest time and invest some money into getting the tone that they want. And I really work with those guys. And it's fun because it's, it's great for me, I get to kind of interact with these guys. And it's not like this hostile environment where it's like, hey, my thing is broken. Fix it. You know, it's also
Host 2 14:23
It's like, you know, you don't have to pay the bills with that anymore, either.
Host 3 14:27
Right. Right. Right. And, and at the same time, we're in the middle of starting my own business, I decided to get married. And at that point, it was I had the question, I was like, I could continue doing this. And it would be difficult for years. Or I could do this on the side and go work at a place like macro fab. So I made that decision. And that was a good decision. Awesome. So that's a it's there's a lot more to it, but that's like the kind of the China years and 10 minutes. Yeah, actually 12 And here's the thing, that amp that I built back in 2005. The first one I did back in high school, I still have it, it still works. It sits in my shop. I use it all
Host 2 15:09
The time that that green one. Yeah, it's the it's it's the the Blitzkrieg, amp. Yeah, I
Host 3 15:15
Had the first logo. I was in high school here, remember this. But the first logo I had was this big tank rolling over a hill of like, inferior and
Host 1 15:27
We actually need to, I don't know if I would picture that we got to get a picture for the podcast.
Host 3 15:32
So after the podcast, I'm going over to my shop to work on some answers. Some people I'll shoot some pictures. Cool. Yeah, so I still have that amp. And guess what? i It's 12 years old. I've never serviced it. It still works.
Host 2 15:43
And at band practice, y'all use that for or y'all we're using it for the bass amp?
Host 3 15:48
Yep. The my bass player uses that every week. It's it's an 18 Watt. All tube amp and it's meant for guitar but man it sounds killer for bass. So that's a little bit of my story. There we go. Someone else write in and ask Parker story.
Host 2 16:05
There we go. Um, so that's, that's gonna take up Steven segment basically, at any rate, so I had I guess it's actually kind of both of us. The resistor resistor. Yeah. Bad news, guys. It doesn't fit in our my 200 pickin place. It's actually it's like four inches too wide. Yeah, fit in that machine. So we're going to redo the layout in Oh, 201 resistors MX, which will have the overall size and so it should fit. Yeah, because it was oh, four twos.
Host 3 16:37
So yeah. Which those are small. By themselves.
Host 2 16:41
Yeah. But there's 40,000 of them on one side. I took it on, like I went over to do the programming. And it fit it would fit into my 500 page gender easy peasy. Yep. And then then I went over the my 200. And then I showed the operator like hey, cuz I've actually never programmed the pic in place before new one. I plug it into my 500 before, but that's 200. And so I went over there. And I'm like, hey, you know, can you show me Give me a quick rundown how to program a part so I can, you know, get this thing going. And he looked at that and was just like, that's gonna fit. It's huge. Yeah. Huge. Yeah. So yeah, we're gonna we're gonna definitely respond. That board gets gets smaller. Yeah. And then the Jeep radio hack. I heard there's some cool stuff. Yeah. So it's actually been working for the past two weeks my jeep now I use it almost every day. And there is a Hackaday article about it. Ooh, yeah. So I got I got hatted.
Host 3 17:46
Yeah. Congratulations. Thank you. So there's two places there's your own personal blog. And then Hackaday wrote about it also.
Host 2 17:54
Yes. Yeah, and some pretty good comments. I think it's 18 comments on it right now. Yep. And they're mostly positive, which is unusual for a Hackaday article. But yeah, so there we go. And so I guess on to the RFO section are evoke. So this week on RFO, down and dirty with contact cleaners. The ti hdc 1080, temperature humidity sensor? And then is owning a 3d printer worth it? Question mark?
Host 3 18:30
Host 2 18:32
Alright, so the first one down and dirty with contact cleaners. This is a article on Hackaday. I'm using this one because we actually had another listener, email in and it's a Emmetts wrote in and mentioned that one of his volume knobs on his stereo amplifier was scratchy. Yeah. And I'm like, I know the exact person that loves to talk about contact clean. And there's an article that came out this week. It was like, the, it's like the gram. We're like, you know, two different topics. And right in the middle is this RFO?
Host 3 19:08
Yep. So contact cleaners. I've used a whole bunch and there is one that I have found that is nectar of the gods. That stuff is magical. It's called neutral. And you T R O L and spy
Host 2 19:23
Mg chemical. That's right. MG chemical doesn't make anything bad.
Host 3 19:27
No problem. You know, what I found in visiting multiple cities and going to their electronics stores. There's always like this little shelf somewhere. Where's the MG chemical shelf, and this can would would exist there.
Host 2 19:43
They also make really good. They're heavy duty flux cleaner. Oh, that stuff is killer. That stuff will like eat anything. It'll take the skin off your fingers. Yeah. and transfer it to the PCB board. Yeah, no,
Host 3 19:56
It's good stuff. They Yeah, they make they make really good chemicals. They're not cheap.
Host 2 20:01
No, they're not cheap. They have a really good rosin flux pin to I can't remember the part number on that.
Host 3 20:07
It's got the little it looks like a Sharpie, right?
Host 2 20:10
Yeah. But yeah, but it's a rosin flux pin, which I ran before macro fab I used for doing consoles, console hacking and stuff, right? Because you did a bunch of Atari stuff, right? Yeah. So yeah, I would do use now that was led solder. And so you use rosin? Yep. Rosin is killer rosin and lead that's that's the secret sauce of long longevity in electronics.
Host 3 20:35
So yeah. Okay, so neutral. contact cleaner. It's like 17 bucks a can. So it's not cheap, but it goes a long way. that'll last a long while. If you do anything with potential amateurs get a cannabis stuff. The thing about it is it is both a cleaner. Well, it's like three things. It's a cleaner. It's a restore Earth. And it's a lubricant.
Host 2 20:58
So it actually deposits carbon back on the wipers. I wish that would be killer. Why is it restored then? It just Are they just say that on the can he it says crap like that. It's a snake oil.
Host 3 21:10
The reason why I say that is you know, most potential amateurs have that little like window in it. That's, that's near the the actual little board where the legs are, give a spritz of this stuff in there and then rotate the pot like 10 times, you will feel grind coming off of the pot, like a lot of times you'll turn a pot and it feels nice. It has a lot of resistance. That's not the pot being like, designed to have resistance that's like grit and grime on the wall.
Host 2 21:39
Because old old Prudential ammeter su they would just put dielectric grease injected in there. Yeah. And which is fine until basically dust and sand gets into the dielectric grease. And it makes a nice like, pastes. Yes. Like, you know, it's just like gritty.
Host 3 21:58
There's like fingers line. And there's just like, just just goop and I nasty stuff in there. But you spray this neutral stuff in there, give it a couple spins, that pot comes back to life. The thing that I've had so many customers come in, and they're like, hey, you know, I've got this vintage amplifiers built in 1964, or whatever they're like, I think it needs to have all the parts replaced and stuff be like, Hey, give me a second. I'll spray that stuff in there, clean it up. The thing sounds brand new, all you got to do is clean it, it, there's been very few times that have actually had to replace a pot, because this stuff will just clean it. And that's it. I always have a candidate available. In fact, I had one at the fab for a while because I actually know that cancelled there. Yeah, yeah, it's on your shelf. And it works for keyboard contacts, too. So most keyboard contacts have a little rubber button underneath it. Just spray a little bit on like a Q tip and just wipe the the tip of it and done. So
Host 1 22:58
I don't know what's in that stuff. And I looked at the 99% rubbing alcohol.
Host 3 23:03
Actually rubbing alcohol lead stuffs really sticky.
Host 2 23:06
Oh, well, because what happens is with rubbing alcohol is it kind of spreads it around. And that's about it, you have to kind of with rubbing alcohol to clean stuff, you need to put it on there, scrub and then wipe it in, then flooded. And so you wash away the right the impurity right?
Host 3 23:25
There, there's something important to note here. Never I don't care what the application don't ever use WD 40 on a potential ometer here's the thing. That's, that's crazy. Oh, yeah,
Host 2 23:36
You're talking about the Hackaday articles, they actually recommend WD 40
Host 3 23:39
Well, uh, yeah, they, they, they talk about DeOxit for a while, and dx, it's great. But the thing is, it doesn't have the lubricating aspect of this neutral stuff. So it works. But it doesn't make the pot feel nice. If you use WD 40 on a scratchy pot, it'll fix it. And you'll be like, Hey, this is great. I guarantee you that pot will be nasty and Scratchy in 24 hours. Because WD 40 does the exact same thing. It's water displacement, it just smears the crap around. And at first it works and then it all dries out. And you just made the problem worse. Yep. Never use WD 40 on a pot or any kind of actionable content.
Host 2 24:14
Yeah, actually is it's WD 40 I never recommend that product anyone. Just in general. I don't see any it does. It's it's like the jack of all trades have something in a can basically, there's so much other better things to use, like when you lubricate, like, let's say, door hinges. Just get silicone spray, silicone lubricant spray hmm. And use that instead of WD 44 Actually, like making stuff not squeak. Yeah, cuz that's what pretty much everyone uses WD 44.
Host 3 24:48
Well, I've used WD 40 on C's bolts. Oh, that's terrible. Yeah, well, no, no, he's penetrating oil. Yeah. Which works so much better. Yeah.
Host 2 24:57
I can't remember the brand or penetration or I get it's a It's an orange can does it have the dude with like, he's flexing? Oh, no, that's liquid wrench. Okay, because that's actually one thing. I've used a lot of different kinds is penetrating oil.
Host 3 25:11
Because you have a jeep.
Host 1 25:12
Yeah, I have a cheap old Jeep. I think it's aero Creole. I'm actually googling it right now. Sorry about this.
Host 3 25:28
Yeah. I've used WD for a bunch of stuff. And I think it's still worth having a can have it sitting around.
Host 2 25:33
Oh, it's an arrow. So it's er. Oh, yeah. Croyle coil. Kr O. L? Uh huh. And, you know, it's good because it has that like old school look on the label. Yeah, you're like, this has got shit that would give you cancer.
Host 3 25:51
But it this is akin to lead solder? Yeah.
Host 2 25:54
It's, um, I think it's the, because one of the best penetrating fluids ever used to get unstuck Bolts is actually ATF fluid, which is read. Yeah, it goes in the on my transmission fluid or on my transmission, and then acetone. mix those together, and then just like, drip it over whatever you need to get rid of.
Host 3 26:16
It sounds like you're making a bomb or something. Well, the thing is, I'm gonna weird
Host 2 26:19
This stuff is red. And smells like a little bit of acetone. So it's like almost that except it comes in a spray can. And that that stuff works awesome. Little bit of that and you know, breaker bar. Go down. Getting anything loose? Yep. Man as a weird tangent.
Host 3 26:44
Okay, next up, yeah. Next topic.
Host 2 26:46
Um, the TI hdc 1080 temperature humidity sensor. So this is another person wrote in and said, I have a good topic for RFO.
Host 3 26:58
It kind of sounds like if you write it, and then we'll talk about exactly right in.
Host 2 27:03
This is Steve. He wrote us a wrote us through let us know about this really cool. I see. What really sets this one apart from other humidity temperature sensors is it it has I can onboard MCU that does all the processing for you. So you can just access it over I squared C and you get the values back. So you don't have to have a analog front end. That's like, susceptible to like to heat or differences in the ability
Host 3 27:34
Of the temperature sensor. Well, I'm
Host 2 27:38
Talking about like, know what yeah, you know what, like, drift and precision? Yeah, different. So it's all contained on a die. And so you can get a higher precision basically, in measuring this kind of stuff. Have you
Host 3 27:49
Ever done an analog temperature sensor? Yes. Like the actual circuitry? Yep. It's a pain in the pan. But yeah, no, it sucks. Yeah,
Host 2 27:56
I did it for thermistors before. Yeah. You know, that whole resistor bridge. And so you can make the nonlinear ability of a thermistor. Linear
Host 3 28:09
Ish, right? But you have to be really careful about how much current is sent through it, because you don't want self heating and all that other crap. That sucks.
Host 2 28:17
Yeah. So this thing's got a accuracy plus minus point two Celsius, which is what plus mine is point eight. Fahrenheit, somewhere around there. It's not bad. And then plus minus 2%. For humidity, which in Houston would be pegged at 98%. That's it's raining. That's 100%.
Host 3 28:36
Right? Right. It never it's never not 90%. Yeah, exactly.
Host 2 28:39
And it's got a built in heater inside of it. So that it will actually when humidity drops, it will dry itself out. And so you don't get false readings or lag in terms of humidity sensing.
Host 3 28:54
No lie. That's awesome.
Host 1 28:55
That's pretty cool stuff. So that's the TI hdc 10. Ed,
Host 3 29:00
Do you know where you can get it as it's like, I'm
Host 2 29:02
Getting Mouser Yeah, it's like three bucks in singles. Something like that. Why is it coming? Like a like, what kind of package coming it's probably knowing these kinds of sensors. I didn't look at it. It's probably then kind of thing. No, it's probably a fr a thin FF fr for, like substrate with a metal can with a hole in it.
Host 3 29:21
Oh, yeah. Okay,
Host 1 29:23
I guess that's what it
Host 3 29:24
Like, like a really big crystal. Yes. That kind of look. Yeah. Cool. Yeah. No, that's that's awesome. Thanks for Thanks for writing that and Steve. Yep. Last topic
Host 2 29:35
In the last topic is is owning a 3d printer worth it? This was another Hackaday article that Steve found. Yep. And if you know CAD, yes, that's that's
Host 3 29:45
Your interesting answer. And so, so I was reading through the article, because in general, my feeling is no. I think 3d printers are super cool. And and just, I would like Love to have one myself. But they just make toys in in some ways in my mind, like, I that's what you think. But they will. I'm not saying that you can't make something good with them. But most of the time when I see 3d printers, it's like, Hey, I've made this little bubble head or I've made a little boat, or I've made a little this or that. And it's like, that's super cool. But it's just I don't get it.
Host 2 30:27
So it's really funny is one of the conveyors, one of the first conveyors we ever bought McWrap. Yeah, has 3d printed brackets that I built for it.
Host 3 30:35
Sure. You've done that. And I've seen, I've seen people on like, Hackaday make little like, you know, this, that that helps. I don't know, whatever tasks that they're doing. But I guess, in my everyday use, I don't run into things that I would need one for.
Host 2 30:54
I'll put it this way. It's like, why when I started learning how to weld is once you master or once you have that tool in your tool drawer. Yeah, you start looking at projects, different ways and how to solve them. Because it's a it's an option, because now becomes an option. Yeah. Whereas before, when I was working on my jeep, I'd have to go and say, Okay, now I need to find a bracket or something that I can bolt together and make it work. But now I'm like, I'm just gonna stick that metal that metal and call it good.
Host 3 31:27
Yeah, okay, I got you on now. No, no, no, here's the thing, the article that was written here, I want to I want to point out something I kind of don't really agree with on there. So basically, what they were saying is, is a 3d printer worth it? And the argument was, if you had a 3d printer, then you could for much cheaper, you could print little toys and gizmos and widgets, that would cost you much more if you bought them at something like Walmart. And so if you compare the cost difference, then the way the article phrased it, or kind of presented, it was like, you save so much money by having a 3d printer. It's like, but I don't buy that crap at Walmart, or anyways. Yeah, anyways, he doesn't like that is not a reason for it to be good for. Yeah, exactly. Because,
Host 2 32:15
You know, we don't have kids. So but like, let's say an action figure, if you can print a really good action figure. Yeah. So to have a printer that can print a really good action figure, you probably wouldn't need one of the higher end hobby printers like a maker gear m two, which is like two grand. Yeah. An action figure, let's say it costs 10 bucks at Walmart? Sure. So you need to print two, we're
Host 3 32:41
Probably all because action fingers probably cost more like 20 or $30. Let's
Host 2 32:45
Say it's 10 bucks, though. Yeah. 10 bucks. You got to print 200 action figures just to pay off in terms of just building toys. Yeah, I think I had like four action figures when I was a kid. Yeah.
Host 3 33:01
So it sort of doesn't make sense
Host 2 33:03
That the I agree there. It's partly, it's a tool to help you prototype or rapidly iterate designs.
Host 3 33:11
I absolutely agree with that. And in that case, it would be awesome. Like, going back to the absented. If I wanted to test out the way a new knob would look on the felt when you grabbed it or felt when I grabbed it, I could print one out, put it on there and be done. And that would be killer that I in that sense. Absolutely. But in my day to day life, I'm not going to spend $2,000 To have a thing that prints out bobbleheads you know,
Host 2 33:37
I would agree with you there. Yeah, but you do agree with me with the other one? Well,
Host 3 33:42
Sure, sure. I can I can see that and I went to our local Makerspace here in Houston just last week. Not TX RX, TX RX. Yeah. And and they had an ungodly amount of 3d printers there. And all of them were printing. If there's any TX RX listeners out there, you guys are awesome. This place is great. But everything that was being printed, there was just like, crap. You know, it was it was just like, great. You printed a big 3d, like version of the letter A, you know, great. What are you gonna do with that? Like, and don't get me wrong, like what no ones don't have to have a use to be good.
Host 2 34:21
What if they were printing their own typeset. So go up, like, you know, how you address on side of your house? Yeah, they printed out the typeset for that. That would be great.
Host 3 34:30
But I really doubt that was happening. You know, so like that. In other words, you can have 3d printers look like that to me.
Host 2 34:38
What if you could have the lettering on Sunday house and Comic Sans?
Host 3 34:41
Oh, gosh. So, you know, maybe I ruffled some feathers with that 3d printers are cool as hell. They're super cool. I just, I just don't see how it works for me. And
Host 2 34:55
Another thing though, is I 3d printed my air filter enclosure for my jeep Will your buddy did? Well, yeah. By designed it and he 3d printed it. Yeah. So I made something that doesn't exist anywhere. It's all custom. And probably you could do it with a lathe, you can do this whole thing with like, it would cost a lot more. That's right, then I actually I'll put this way is because it's pretty big. That thing is like eight inches by six and a half inches in diameter. Yeah, and it's a cylinder that would cost more in material loan on a lathe than it did if you bought the 3d printer is printed on and the material for the 3d printer. That's true. I think that was like it. I think I got it quoted through some online places just to make it out of like, no ABS plastic, there's like three grand. Yeah. And I printed it with like $2 and material.
Host 3 35:50
Right, right. Right. And and that microfiber, I've I've had a couple things printed, I made a transistor standoff for a customer that needed a specific height of a transistor on a board. I've made some pins, straighteners, and some handful of things. So I've used it. And it is useful, but I guess I guess all I'm getting at is like myself personally. Yeah, I don't see myself owning one. But regardless,
Host 1 36:15
We should get a nice one at macro fab. We should get a nice one just so we can.
Host 3 36:19
And then toys all day.
Host 2 36:21
No, it's just one of those. Like, we now have that in our toolbox that we can use. Sure. And because like you've been doing all the configuration and all that stuff in, you know, instead of having to buy that ginormous aluminum plate that you're attaching a little tiny scanner to what if you could just make a 3d printed bracket that works.
Host 3 36:41
Hey, if it can do that, if it can print a big giant, metal like plate. If it does the same job great. I mean, I'm all in. But if it just looks like some plastic gizmo, and if it makes my project look crappy, I don't want to use it, you know? No, it's got to
Host 2 37:00
Look pro got look pro got to look Pro. And so that will wrap up this episode of The McWrap engineering podcast. This was episode 56. We were your hosts
Host 1 37:13
Parker Dolan and Steven Craig later everyone take it easy
Host 2 37:23
Drink a beer. It's National Engineers Week.
Transcribed by https://otter.ai