- Derek Brodeur
- Applications engineer involved in writing control software for atmospheric and vacuum robotics used in the semiconductor robotics industry
- Runs a YouTube channel called “The Current Source” where the primary focus is on electronics
- What made you want to start a Youtube channel?
- Favorite old Project that you have completed?
- Projects that you are currently working on
- David Kronstein is letting Derek borrow one of his high-speed Chronos cameras, so Derek is going to use a high voltage capacitor and giant SCR to fry some electronic components and hopefully get some good footage
- Contact bounce in high speed using the camera (and ways to mitigate bounce)
- 16-bit flip dot array for demonstrations (instead of boring LEDs)
- Build a TEM cell from aluminum scrap
Visit our Slack Channel and join the conversation in between episodes and please review us on iTunes!
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 1 00:11
Welcome to the macro fab engineering podcast. I'm your guest Derek Broder.
Host 2 00:14
And we're your hosts Parker
Host 3 00:16
Tillman and Steven Craig. And this is episode 103. Derek is an Applications Engineer involved in writing control software for atmospheric and vacuum robotics used in the semiconductor robotics industry. In his spare time, he runs a YouTube channel called the current source, where the primary focus is around electronics.
Host 2 00:35
So Derek, is there anything else you want to add to your background before we get this podcast started?
Host 1 00:41
Could have said it better myself? Yeah, I'm an applications engineer. I work for a semiconductor robotics company out of Germany. We're a small company that represents to other larger robotics companies out of Japan. And I write software that controls the robots that go into manufacturing equipment. So that could be like a CVD tool, or a plasma Etcher or photo photo lithography tool. So fabs like TI, or Intel would buy this equipment to make these wafers. So as you know, the microchips are, are basically grown on these silicon wafers. And the reason that we use these robots is so that people don't handle them manually with their hands, because that could introduce particulate that would cause block death and other issues. Dorito dust test, dandruff, you know, the usual stuff. So I basically am involved in the sales tradeshow kind of stuff. But my primary function is to raise software that controls it communicates with the fab host controller, or a local computer that controls everything.
Host 3 01:50
Is it like just a kind of a big PLC thing?
Host 1 01:54
No, it's actually a dedicated controller that runs a couple of different microcontrollers. Don't ask me what they are don't remember. But it runs. It runs its own firmware. It's got IO and, you know, Rs 232, land connections that you can control all kinds of other peripheral stuff. So the robot is kind of the centralized thing inside of the equipment that controls a lot of the slip valves, load locks, and all that kind of stuff.
Host 3 02:18
Awesome. Have you have you actually been to any of the fabs to see the robots?
Host 1 02:24
Occasionally, it's more, I'll visit the actual equipment manufacturers. Not so much in the fab. But there are a couple of times that I have gone in just to make sure everything is working properly. So I do some traveling, I get to go overseas every now and then. But a lot of its local.
Host 2 02:41
What's the coolest place you've ever been to then?
Host 1 02:45
We have a customer out in Austin, that that's pretty cool. Those guys are pretty neat. They're you know, they appreciate good beer and their old skaters, you know, old skaters from the 80s. So we get along pretty well.
Host 3 02:57
Skaters. churton semiconductor farmers.
Host 1 02:58
Yeah. So that's my kind of environment. So I appreciate going out there every now and then. And host it's a cool city anyway. Not as cool as Houston though.
Host 3 03:10
Host 1 03:14
So yeah, in addition to that, like, in my spare time, or in the YouTube channel, the current source, like you already said, and I just make videos that are about general electronics, it could be anything that, you know, I just find cool in a magazine or an article or just something I'm working on, on my desk that I think I should dedicate some time to, that somebody might benefit from. So
Host 2 03:36
Yeah, so I guess we'll just jump right into the YouTube channel. So what made you what made you want to start a YouTube channel,
Host 1 03:43
Um, when I, when I go, when I try to find information for some kind of circuit, or when I understand something a little better, you know, I usually hit a, like everybody does Google or look up data sheets, application notes. But YouTube has also become a really great resource for electronics and learning new things. So I watch you know, Dave, and Alan walkie and all the usual suspects, and I thought maybe I could contribute some other way, building circuits and just showing things that they might not be or, you know, in my own kind of flavor, so. And I've always been kind of an introvert. And I think as I get older, I care less and less. So I just thought I'm making this stuff anyway, right? Like, I've been making stuff since I was 10 years old, and I'm too lazy to make a website. So I thought well, I'll just turn on the camera. And you know, just show people what I'm doing. That's cool.
Host 2 04:36
Yeah, so on the on the it's kind of weird that way, right? Where, like, that's what I built the blog to do that because I guess I was afraid of being on camera. So yeah, that's interesting. The way you just went jumped all in to check the YouTube.
Host 1 04:55
Well, yeah, I mean, I wanted to show people what I was working on but in a I originally started a blog, I guess, and it just takes a certain level of dedication. I don't have, I'm not gonna sit down every day and just do that it. It was a bit of a jump in the beginning because like I said, I'm an introvert. And I'm, every time I sit down in front of the camera, I'm uncomfortable, I don't want to be there. But after five minutes, it just kind of warm up and the, the process of editing, I mean, you have to watch yourself, you have to listen yourself. And that was difficult. With the first video, I actually made a video about switch mode power supplies was the first thing that I did. And I just couldn't stand listening to myself. So I ended up deleting it. Totally, totally trashed it,
Host 2 05:36
That that's exactly what we did with our first episode of the podcast. Oh, it was so bad. Yeah. Like, yeah, never leaves the house.
Host 1 05:46
Yeah, exactly. So I just trashed it. And I stepped away from it for like six months, but then I did the, the measuring distortion, video, video number one. And I said, you know, I'm just gonna put it out there. And it was a little bit of a difficult thing. Because when you hit that public button, you know, you're kind of, I guess, like releasing your video out under like global peer review, you know, so, people are either gonna love it, or they're gonna hate it. And in the beginning, absolutely. Nobody's watching, right? So yeah, there's that level of comfort. But you also have to realize if you can leave that there, people are gonna see that in a few years, you know, so
Host 2 06:29
I've had people like, click of like, comment on a video I made like, eight years ago, and we're like, why did you make this video is like the comments. I'm like, yeah.
Host 3 06:38
Go check out your backlog. That's for sure. Yeah. And I have to admit, that's, that's you chose to pretty beefy topics for your very first video, I mean, switch mode, power supplies, and distortion, analyzing that's, that's a lot for first video. Yeah,
Host 1 06:55
The, the power supply thing was pretty cool. Because I was looking at the power supply that I had in my DSA mid essays from like, 1981. So it's this huge, enormous thing, these giant diodes and caps. And it basically compared it to a tiny one that has the same power output. And just how things have evolved over the decades was interesting. But I just one of the things that I've learned is that the pace of the video, you've got to speed it up, like the first five videos, or whatever I did, I can't listen to them, because they're just they're so slow. Like, now, if you notice, there, it's the editing is much more fast paced. And yeah, it's easier to watch, you know, I am learning what people want and what I should be doing. And, you know, just that tendency to just ramble on, I'm trying to not do so much anymore. Well,
Host 3 07:43
Okay, so I have no information on this. In fact, I'm curious about it, I would think or guess that engineers are maybe a little bit more tolerant to rambling or listening for something because they like the topic, or they like, what the way the video is going. Whereas because I mean, I've heard plenty of advice, where, you know, if you don't capture someone in the first five seconds of a video, they're not going to watch anything more, I would think an engineer would do would stick around a little bit longer if they know what the topic is about.
Host 2 08:12
So I'm the, I guess, the exact opposite out, like, see how long the video is, and like skip to like a third of the way in and see where it's at. Okay, maybe
Host 3 08:20
Host 1 08:23
Yeah, that's a good point. I mean, I will watch something if I'm interested, truly interested in this subject, I will sit there and I'll watch somebody take a nap for five minutes. Right. But if there's somebody who's building something, and they're just taking too long, I will skip like to the end of the video. And it's weird looking at the statistics, like YouTube gives you some statistics on the back end you can look at and the average view time for one of my videos is four minutes. So that's like a third of, you know, the videos length or a quarter of the videos length. So I don't know if I've hit the nail on the head yet, but I'm trying to get better. So we'll see what happens.
Host 3 09:00
Host 2 09:02
I was it's one of those things where like, YouTube, it's like, we look a lot of videos that people put out on YouTube now, mostly about 10 minutes long. Right? I think that's because of monetization and stuff. But like maybe that's also like the average YouTuber watches like only like a 10 minute video.
Host 1 09:24
Yeah, if you look at what what's suggested out there, they say to make like a when you're starting out, they say make like a 510 minute at the max video. And there are guys like, I don't know, if you watch the signal path blog, where he does like super advanced RF stuff, and he'll go really in depth for like 45 minutes, sometimes an hour. And I'll watch that because that's what I want to see. But you know, if it's something else that that's a bit you know, long in the tooth.
Host 2 09:50
Yeah. So, this is kind of jumping back to earlier where you were, you did the YouTube channel to kind of contribute back to because you were like Googling and search on YouTube for how to get stuff done. Have you ever, like Googled something and found the answer in one of your own pieces of content?
Host 1 10:11
No, no, I have not yet. That'd be awesome. No, I think with only I don't think I'm contributing all that much yet. I mean, I've got almost 3000 subscribers, which, you know, when you look at the grand scheme, isn't that great. But I was actually, I tried to separate my work from the YouTube thing. So I don't want you know, my video showing up on my boss, my boss's desk. Just, you know, I'd like to keep those two things separate. But I was actually in the office in Germany, and one of the new electrical engineers that we hired, was looking up something and he was showing me Dave Jones, you ever see this guy and one of my videos popped up, and that's great. I just had to like, divert his attention somewhere else. That's pretty funny.
Host 3 11:00
So so how long have you been doing it for?
Host 1 11:03
So about two and a half years now? I think yeah.
Host 3 11:07
Okay, and how many videos you have up?
Host 1 11:10
I think, total 35 or 36? I mean, there are a couple that are just little announcements. But yeah, I don't, I don't follow a super rigid format, or a lot of YouTubers will release something every two weeks. But I found that, you know, I've got a full time job, got a family, that stuff takes priority. The videos are kind of secondary, unfortunately, you know, I'm not going to make a full time job out of it. That's not my goal. So I release things whenever, whenever I can. And unfortunately, sometimes that's like every four weeks, sometimes it's too, it just depends on, you know, the difficulty of the video, sometimes it just talking about flipping bits, right. And that's pretty easy to do. But I think the most difficult video was the Doppler shift video. So I was running around buying sheet metal making antennas, I didn't have this coax, I had to go buy connectors, and just, it was poor scheduling. So a lot of that stuff is really, really worked at. I do like three or four videos in parallel. So I'm always procuring parts, I'm planning a shot list, I'm writing a script, if I'm doing a voiceover, that kind of stuff. So I think things have become a lot more efficient. So you should probably see things every three weeks now on average, as long as not traveling. So,
Host 2 12:21
Or kids sick or something.
Host 1 12:23
Yeah, yeah. And that stuff definitely takes priority.
Host 2 12:29
So what's the we've talked about a couple of projects so far, but what's your favorite project you've done so far? Um, or, and I guess we can also jump into like, what made the Doppler one really hard to do? Those.
Host 1 12:45
Okay, let's do a Doppler one, because we're already there. I, I ran across this article in the ar l handbook. So American Radio Relay League handbook, which is a ham radio, the Bible, I guess you could say,
Host 3 12:59
Sounds like a page turner.
Host 1 13:01
Well, I mean, it's a great book, if you're into electronics, you don't even have to be a ham radio operator. It's it's everything that you're going to learn. As a doubly, it's, but it's really packed pretty densely in this mag in this magazine, it's a book, there's a lot of RF stuff in the back. So there's really a lot of good information if you just want to learn something quick, probably not as good as the art of electronics, or as focused on general electronics. But there's a lot of good info in there. But there was a, just a paragraph about radio direction finding techniques. So you take like four antennas, arrange them in a circle, and you switch one on at a time at a certain speed. And depending on the direction you're going, you can determine by the amplitude and the phase shift of the signal that you're receiving, you can find out where that source antenna is. So and I'm probably doing a pretty bad job of explaining it now. But I want us to understand it better. So there was a lot of experimentation that went on before I even did a video to make sure that I could explain it in a way that anybody could understand. And also procuring the parts. I never used pin diodes before, the coax had to be a certain length and
Host 2 14:15
I never heard that before.
Host 1 14:18
So I'm gonna have to So PIN diode is used a lot of times to switch antennas on and off. And I'm going to revert to Wikipedia.
Host 2 14:28
Yeah, I actually, I said, I asked that question. And I heard click, click click
Host 1 14:37
Yes, Wikipedia says it's so there's an intrinsic layer. That's right, had to reach back because it's been a while but there's an intrinsic layer in between. So there's an NP junction and they're heavily doped and what you you can use them to switch on RF, switch it on and off, and it turned out that back and use these diodes with a DC bias to turn them on and off to change the, the what's the region in the center there? Oh depletion region, the depletion region with a DC bias, you can turn these antennas on and off and hooked up a microcontroller, you can switch each antenna on and off to control this effective rotation of the antennas.
Host 3 15:25
So so it's kind of almost the boundary between a diode and a transistor in a way. Yeah. That's cool.
Host 2 15:37
I like how I thought it would be something else like pins stood for something. No, it's the P,
Host 3 15:42
The pn junction with an eye junction. Which is basically a base on a BJT. Yeah, just minus the actual physical connection to it. That's cool,
Host 1 15:54
Right. And you can control control the size of the that intrinsic region. So that was cool. Because I never used those before. I think, you know, some of the things like SDRs and pin diodes that they mentioned, you know, in textbooks and in school are the things that I don't understand 100% And that's what I want to do videos about so I can better understand or get that last 10%
Host 3 16:17
Yeah, that's pretty bold to go and pick something that you don't know about, and then have to learn all about it. So you can make a video. That's really cool.
Host 1 16:24
Well, yeah, I think I think some people, I'm not gonna name names, but I'll make videos and you know, it's almost obvious that they don't fully understand it. But they're, hopefully you're
Host 2 16:35
Not talking about our podcast.
Host 3 16:36
Yeah. Because you might be slightly accurate.
Host 1 16:43
I'm gonna say that, you know, and I think it's important that people that are getting into electronics, you know, not everybody is an expert. You know, you're you're learning all the time. So I'm learning all the time. And I hope that comes through.
Host 2 16:56
I would say the one thing about the podcast I've learned about myself is how little I know about some things. So like, they're like 10 diodes, I had no idea those actually existed.
Host 1 17:07
That's no idea did have difficulty explaining it.
Host 3 17:11
Well, they don't seem like they're particularly easy to understand. Just off the get go. Yeah, yeah. Yeah. Well, that's great. So what, what projects are you currently working on?
Host 1 17:23
So I have a cool project coming up where I don't know if you've heard of David Kron Steen. He's at Tesla 500 on Twitter. He's got that high speed Kronos camera that he developed on his own.
Host 2 17:38
Well, that's impressive by itself. Yeah,
Host 1 17:41
So I just reached out and contacted him and said, Hey, can I borrow that camera, I've got some, some ideas I want to work on one of the things is contact bounce. So I want to take a high speed video of an actual really doing contact bounce and showing it on the scope. And then other ways to mitigate, you know, avoiding that or filling in those contact bounce gaps. So
Host 2 18:02
That sounds really badass.
Host 3 18:04
Yeah, that's, that's really cool. I mean, are you are you gonna do that under a load, so you can see it spark?
Host 1 18:10
That's a good idea. Cuz that would be really cool. I'm gonna try every possible way that I can. I don't think I'll be able to catch the cathode ray on the oscilloscope changing because it'll be too dim at you know, I want to synchronize them side by side. I don't know if that's actually going to work. But, you know, I'll definitely try that. I'll try to stick in under load and try to get it to spark
Host 2 18:33
Yet because the the big thing Well, relays is underload is taking contact real easy. And you know, there's bounce and stuff there, but it's actually unsticking the contacts too. Oh, yeah, they
Host 1 18:45
Can fuse together. Sure. Yeah,
Host 2 18:47
That'd be really cool to like, when it's actually ripping away and how the, the,
Host 1 18:51
I guess the contact will probably flux a lot before it snaps off.
Host 3 18:56
It's gonna break like a really tiny weld. Yeah.
Host 1 18:59
That'd be great. We'll try that. And I've got that's actually a good point. Um, I thought, what else could I do with that? So I've got this big fat SCR that's in a puck form factor, and a high voltage cap that I'm going to put across some devices and just basically destroy them under about 12 1200 or 1500 volts. I'm not sure.
Host 2 19:23
I think I think I've actually emailed in on a previous podcast about that puck.
Host 1 19:27
Yeah, yeah, I bought that thing and you guys were asking what people are working on and I you know, that thing I got at my local surplus shop and it just kind of sat on the shelf and I'm like, What am I gonna do with this? So I think I finally found a good use for it. It's calling it's calling me up I wipe the dust off and we're gonna write actually tested it out the other day works okay. So
Host 3 19:50
It's not every day that a hobbyist needs, you know, a switch for 600 volts 100 amps, you know?
Host 1 19:56
Yeah. I think this is has a peak current capability of 75 Killa amps or something like that? That's awesome. So it did the problem is getting all the energy out of the capacitor as fast as possible. Right. So the only cap that I have is a paper and oil capacitor. Those are pretty fast. Yeah, yeah. I was hoping for a little bit more, but they're pretty pricey on eBay. Oh, yeah.
Host 3 20:21
What? What size? Is it? I mean, capacitance.
Host 1 20:25
I think it's 75. micro farad. At 1200 volts is the max.
Host 3 20:32
Oh, wow. That's, that's pretty beefy. Yeah,
Host 1 20:35
I mean, when I did that capacitor video, I was just using basically a knife switch to switch it in and out of circuit, which I think a lot of energy was wasted in that arc. So I'm hoping that the SCR just dumps it. I think it should dump the if it's 1200 volts, I think it dumps it in about five microseconds or something like that. So I think the limitation will be the internal resistance of the capacitor. But we'll see.
Host 3 20:59
It's bringing me back to the days of having to calculate joules. Oh, yeah. That's one of those units where it's just like, you calculate it, but you don't really have like, a feel for
Host 1 21:11
It. Like, yeah, you have no frame of reference.
Host 3 21:13
Yeah. Like, what's a jewel?
Host 2 21:15
Wonder like, and then more your professor be like, oh, yeah, it's this many. Oh, it's like this many electrons. And it's just a, okay. Yeah, see electrons,
Host 3 21:24
Right. But but at the same time, it's like, one joule, is that a lot? Or is that a little of what you know? Like, it just doesn't connect?
Host 1 21:32
So I think that that capacitor video, I had a sheet of a blank bare copper PCB, it was double sided. And I was just trying to figure out how many electrons were on the surface. And the number was so high, it's just you have no concept of what that even means. Yeah. So yeah. So yeah, that's coming up. So we do the contact bounce thing. I'm currently working on a 16 bit flipped array. I'm kind of switching. Usually, there's a permanent Magnar permanent magnet mounted to the disk. And then there's a coil that changes polarity and flips the disk, this is gonna be the opposite.
Host 2 22:13
Ah. So where did you get this array at? Because I've seen people get these at like, surplus shops, and I actually almost went to a, it was the Metro here in Houston. But they were replacing all their buses, they're replacing all the dots with LED and show up and there's just like, tons of people just try and snag those displays.
Host 1 22:38
Oh, no kidding. That'd be awesome. No, I'm just making this from scratch the bottom, it's actually cooler. I hope it works. It worked on a breadboard. So I just finished building the there's a 16 bit driver, it's a push pull circuit connected to a microprocessor. And the the dots are actually made from the circuit board material and of edge to planar coil onto them. And
Host 1 23:04
That's pretty cool.
Host 2 23:06
It blows my mind at the moment. I gotta see this, well, I guess, wait for the video
Host 1 23:12
For a little eyelets on the on the poles and they can flip on those islands. And I found that you can't use a high voltage or higher voltage because they'll arc and they'll they'll actually get welded so you have to use a current source. So I made a push pull current source that's gonna flip those things. Hopefully, we'll see.
Host 3 23:30
Oh, so you just have a fixed current that you push into it and it flips. Yeah,
Host 1 23:33
Yeah, it works on a breadboard. I'm just hoping that the whole thing works.
Host 3 23:37
So okay, I have to ask are using like are you going to paint them neon green like the like the bus ones or
Host 1 23:44
I've got the I've got the yellow airbrush pain yeah awesome.
Host 3 23:49
They got to be that weird yellow green color shirt truce right I don't believe that churches Park Yeah, searchers
Host 2 23:56
That yellow that yellow green looking for truth Yeah, that's what that chorus
Host 3 24:02
I don't know. I guess in my mind it's a slightly different that's the yellow green Oh shoot. I yeah, I was pulled it up that's that's pretty much well done as well.
Host 2 24:13
Yes, really? Okay, this is a weird side tangent is short truth like hearing the golf when you go fishing like the lures the US have some short truce on it. Nothing in real life is that color yet it makes fish go crazy and want to bite it's
Host 3 24:32
So it like sort of like green screen color. They pick that because it doesn't exist in nature. Probably. Yeah. And the same with if you do blue screen to that, that doesn't exist.
Host 2 24:42
So you mean that it's kind of like a blue sky.
Host 3 24:46
But that like particular shade that one particular shade of green and blue don't arrow? I'm talking about my ass now. Yeah.
Host 1 24:57
Which by the way, that green screen is very difficult to do. I tried to do that for one of the videos where I was going to put a background. But the problem is when you bounce the light off of the wall that you've painted green tends to bleed into your shoulders. So it makes it look like your arms are eroding away. I haven't exactly mastered that yet.
Host 3 25:16
Isn't it a matter of just getting the light? Perfect on you? I think that's kind of
Host 1 25:22
It's got to be evenly distributed on the wall behind you. And you have to be far enough away from it where you don't get the reflection.
Host 2 25:28
Right. Yeah, it's like it. And yet to have the right color. shirt and denim. Right.
Host 1 25:34
Yeah. And it has to be, they have a special paint for it. That's really non reflective. I was just using matte paint from the local hardware store with an awful green.
Host 2 25:45
It was free.
Host 1 25:47
Basically, yeah. So yeah, there's that. I'm working on a attempt sell
Host 2 25:55
Towards the stem cell.
Host 1 25:58
So when you develop a product, and you need to go for, you know, you need to go into the big anechoic chamber with the antenna and do your FCC testing, which I'm sure a lot of listeners have had to go through at some point. You go in there, you spend X number of dollars, they test it, they tell you up. Sorry, you failed. Yeah, now you have to go stick a bunch of ferrite beads on everything. So either.
Host 2 26:24
This is the thing about that, though. Okay. Is you you fail, right? And they're like, Oh, can we just stop testing? Like, No, we got finished test. I'm like, No, I want to stop it. Now. It's I can fix it. Because Camino two hours tested in that chamber.
Host 3 26:37
Oh, yeah. But the they tell you oh, we might fail further out. I don't care if I failed.
Host 2 26:42
Because map. Yeah, fix it now. Right? Yes.
Host 3 26:45
Yeah. But that you know, money. Yeah, they're
Host 2 26:48
No Kenya for that, though. Oh, yeah. That per hour base charge.
Host 1 26:53
Right. So then you have to mess with it, and then come back. And sometimes, I guess, depending on the AMC house, you know, the village just jump back in or will charge you again, I don't know. But the term cell is basically it kind of simulates that environment. It's it's a 50 Ohm transmission line, right. But it's expanded. So it's got three layers to it. Kind of hard to explain.
Host 2 27:16
Oh, yeah, I know what you're talking about, I've seen before. Yeah, there's
Host 1 27:19
A 50 ohm load on one side, and then you you have your spectrum analyzer connected to the other side. And you basically stick your product inside of it. And any thing that disturbs that transmission line will show up on your spectrum analyzer. So it kind of roughly simulates that kind of testing environment. So I've got a bunch of aluminum leftover from the Doppler shift, and I'm going to chop that thing up and make make a timescale out of it. And from what I read, you can get within like six dB of the actual measurements.
Host 2 27:52
Yeah, that's actually pretty good. I didn't know they were that good.
Host 1 27:56
I don't know if that's true. I want to I want to kind of test that out. But anyway, it'll
Host 3 28:02
Aluminum foil and two by fours, right, they'll get you within six dB. There you go, making a big old pyramid out. I've seen worse.
Host 1 28:13
So so it, but it allows you to take relative measurements, right? So if you're putting out this much noise, then you should be able to take that board out of the temp. So try to find the source of the noise, rectify it, and then put it back in and see if you've improved it.
Host 2 28:26
Yeah, that's the big thing about um, was it a pre compliance testing exam is, is all it's all relative, because you can, you can turn it on, and you're going to have all the noise that exists in your area being pumped into your, you know, signal analyzer. Right? So yeah, and then the whole, the whole thing is just relative. So you put your device in, see how much it affects the environment, basically, and then tweak from there?
Host 3 28:56
Do we get a baseline? Yeah. Well, I've
Host 2 28:58
Always figured is if you can turn on your device, and you don't see the noise floor in the room change, you probably okay.
Host 1 29:09
Another thing that spectrum analyzers are capable of doing is measuring the ambient environment, and then you can subtract it out from the measurements you're currently taking. So, how to do that along with it? I think that would make sense. So
Host 3 29:25
Do you hook up an antenna to one of the inputs?
Host 1 29:29
The transmission line is kind of the antenna, right? You've got a 50 ohm load on one side. It's like you're connecting electrically, a 50 ohm load to your spectrum analyzer, but it's like you've cut open the coax and shoved in your circuit.
Host 3 29:42
Ah, okay. Okay, I got you. I got you. That makes sense. Yeah.
Host 2 29:46
Yeah, cuz the the tops are the shields and a metal plate is the signal path.
Host 1 29:51
Right, right. And you stick your product on the bottom shield of the coax. Yep. Yep. So that might be an interesting one. that'll take a little bit of work though. And I'll be cutting some aluminum on the table. So I which scares the crap out of me. Oh,
Host 2 30:07
I do that all the time
Host 3 30:07
To say that it's not that bad. It does seem scary. You know what's actually scarier is cutting Plexiglas on a table saw. I hate that, especially because it smells terrible and gets crap all over you. And it can bite and weld. cutting aluminum is really not that bad.
Host 2 30:24
Okay, well, that makes me feel aluminum is very noisy cutting on tablesaw. But yeah, I've never had any. I mean, I've had this blade on my tables on abused. I've cut aluminum, and I've cut Plexiglas, acrylic plywood, and just cuts in some cedar planks couple of days ago, and it kind of just fine. So somehow this $10 You know, Home Depot, saws doing pretty good to trooper? Yeah. All right,
Host 1 30:51
Yeah, I've used the chop saw to cut aluminum before, but never tablesaw. So we'll see how it goes.
Host 2 30:57
Or not. If it doesn't go, well, we won't hear back from you.
Host 1 31:02
Video so anyway, yeah. Next week, I'll be in Germany. So I was thinking about doing a video while I was out there about scaling down like a 4.2 lithium ion battery to an acceptable level for measuring with an ADC on like a 3.3 volt part. Because that was one of the things that I wasn't really used to is. I'm used to plugging things into the wall, Who cares what the power consumption is, and you know, you just let it rip. But I've been doing a lot of battery power, Bluetooth Low Energy stuff. So I start incorporating some of that. Some of those things into the videos in case people are interested in that.
Host 2 31:48
It usually my, my solution to, like things I've designed is just put more batteries in it.
Host 1 31:54
Yeah, just put like a giant like RC car battery on it.
Host 2 31:58
Yeah. Or I've been going more towards like 18 650 style cells. And you just like, you just carry extras of those in your backpack, and you'll find
Host 1 32:08
Some right. Yeah, I've been doing some weight critical things for the semiconductor stuff. So we have to make we're trying to make things the same weight as a wafer, which is a little bit of a challenging design constraint.
Host 3 32:21
But that's like for balancing or something.
Host 1 32:24
So when you when you program a robot to like, extend its arm. Depending on the size of the robot and the rigidity of it, you have this cantilever sticking out in space, right? So it wants to droop. In fact, we have some really, really big robots that are, you know, 20 feet tall. And when you when you extend that out under a payload, it'll droop like a few inches. So things get a little more complicated there. And that's one of the things we have to consider when writing software for this stuff.
Host 2 32:55
The actual droop of the mechanical part of the arm.
Host 1 32:59
Yeah, you have to start taking some mechanical things into consideration when the robots scale up. So
Host 3 33:04
Host 1 33:07
Yeah, it's not fun.
Host 2 33:12
So do you have like a model, I guess you have a software model that replicates what this arm does in the physical world.
Host 1 33:22
So yeah, we have simulators. For the robots, a lot of that stuff is, you know, they have really advanced mechanical design software, CAD software out there that will simulate this kind of this kind of stuff. But as far as I'm not sure what they're using. But when I get it, we just hook it up to we have an actual simulator. So it's a box, and it's the same electronics that run the actual robot controller. So you've got the same kinematic control systems and everything in the same amplifiers. So it's simulated pretty close to the to what it will be in the real world as far as acceleration, deceleration how fast it can move. So if they, if the customer wants to get throughput numbers, we can just run it on the simulator and do do all that stuff. But yeah, there's actually plugs into our computer and we can see a 3d model of the robot spinning around. It's pretty cool. Yeah, I
Host 2 34:12
Guess that would be difficult. Yeah, I guess. Yeah, I was gonna say is, I bet you the process of pushing new code to one of these 24 robots is a little bit different than, you know, just sitting you know, go on your computer.
Host 1 34:28
Yeah, you have to really, because there's nothing around the robot in this 3d environment, you really have to think about what's happening in the real world, especially if you're pushing something out, you want it to be safe. And you know, there are things that it could collide with all around and usually the the end effector is which is the technical term for the the hands on the robot are either made out of ceramic or some kind of material that will basically crumble right? So and they're expensive, it could be carbon fiber. and you don't want to destroy him. So you really have to test things out pretty thoroughly before you go and hand it off to to the customer. So it's interesting.
Host 3 35:09
Have you guys ever had a robot just completely freak out?
Host 1 35:15
We haven't had a robot freak out, but I didn't have. So we do we do semi con every year. And this is the semiconductor convention, everybody, you know, just like any other convention, I show off their cool, cool new stuff. Yeah. Yep. So we always have robots there. And I work from home. So I was at home. And at the time, we were in a different place, but we had a shed, and I actually had them shipped to my house, there was this huge equipment front end module, you know, the big monster things you see on the front of equipment in the fabs. I had that put into my shed in the backyard. And I guess it wasn't paying attention. I just it was late. And I had the depth robot extended into the load port, which is the one of the doors on the front. And I commanded it to close the door. Ceramic end effector just got Ceman totally destroyed. And it was a pretty expensive piece of equipment. So
Host 2 36:12
I'm actually surprised to just they, they the first of all, they get it got approved, just to put it in your shed
Host 1 36:23
Well, and you're the only software guy working on something, they'll do anything crazy. Yeah, yeah. But we got to work individually. Unfortunately, I had to get another pair of end effectors which Yeah, the boss man was too happy about.
Host 2 36:39
That sounds like an awesome Oh, it sounds like an awesome job. It's like I get, you know, program robots and stuff. And you're like, in my shed
Host 3 36:45
Host 1 36:50
Know, it's cool. And it's fun. It's, it's, it's it can be a little high pressure, though, you know, because when a company orders a robot, it's usually one of the most expensive things on the equipment. So you usually have somebody just perched on your shoulder while you're, you know, programming, and it makes it a little bit of a stressful environment. But, but it's pretty cool. It's pretty cool moving motors around and watching things, you know, perform tasks in the fab that you normally have no view into?
Host 2 37:19
Yeah. Actually, well, I see what it's like, we need to finish. So I've got no I have one more thing I have one more thing is. So if you want to get into doing like, wow, anyone can make a YouTube channel. But if you want to get into like doing like robotics and stuff like you do, how do you get started in doing that?
Host 1 37:43
I would definitely follow it like a computer engineering degree, or electrical engineering, I think I kind of got lucky. I am interested in a lot of different things. So I try to learn as much as I can about you know, electronics, welding, programming, machining, you know, and just don't be scared to jump in and get your feet wet and just start doing this stuff. A lot of people are intimidated by soldering and surface mount. You know, just go out there, get yourself a kid. Learn as much stuff as you can, you know, get into school, stay in school, and you know, the experiment,
Host 2 38:22
Don't do drugs,
Host 3 38:24
Drinking milk, do your homework,
Host 2 38:27
Eat your vitamins.
Host 1 38:30
Just get your hands dirty. And you know
Host 2 38:33
What, cuz it's like, you know, when you're growing up, you're like, I want to build robots. And it's like, okay, how do you get to building robots, which is what you get to do. Yeah,
Host 1 38:41
I actually found my resume online. After, after I left I worked at Texas Instruments for for about 10 years in Dallas. And I was in the semiconductor, obviously, area, and I read a lot of software there. But I got kind of kind of burned out on the software thing. And I, I took off and went and worked with my brother in law as a graphic designer and photographer for a little while. And I learned a lot of cool stuff there. But it wasn't my thing, you know, engineering and tearing things apart. That's, that's my thing. So I just stuck my resume out there. And these guys happen to be in town from Germany. And they they actually found me so I think the thing was, I had a large skill set. And a lot of it was geared toward robotics. You know, I played around, I'd made some three axis CNC routers, from scratch. You know, if you put that kind of stuff in your resume, and you apply to these jobs, you've got a foot in the door ahead of anybody else. That's just you know, recent college graduate hasn't done any hobbyist stuff or anything related to electronics, you know, just get out there. Start making boards, start making your own robots, you know, learn stuff. Yeah, I
Host 3 39:51
Would. I would almost say that's probably one of the best things to tell someone like how do I get into robots, just start making them you know, and like if you Want to you'll figure out the way to do it. And I know that's like, that's not a lot of like information. And that's probably not what people want to hear. But, but really like if you if you want to, you'll start researching it, you'll find ways you'll find groups, you'll find internet sites, you find whatever it needs to get it done.
Host 1 40:16
Right. And it's way more accessible nowadays than it was. I mean, there were people making CNC routers, and that's how I got into it. But you've got 3d printers that work along the same kind of principles of acceleration, deceleration, open closed loop control systems, you know, learn that stuff. If somebody asked you that in an interview, and you know, you can explain it at least even at a high level, you know, you're ahead of other people. So, yeah, awesome. Definitely.
Host 2 40:43
So, Derek, where could other people find more information about your YouTube channel and you
Host 1 40:50
So you can go to the current source. com, I've got my contact information. If you guys want to contact me, you can do it through there. If you have ideas for the high speed camera, come and contact me there. Just go to search me out on the current source on YouTube. And I'm also on Twitter at T current source.
Host 2 41:09
Oh, you've got an old YouTube URL too. It's actually the current source 555 Correct. Yeah. Because the new if you make a new YouTube channel now it just gives you like a hash string. That's your channel. Yeah. So the OG stuff is you actually have your name was the extension or the URL.
Host 1 41:31
Okay. Yeah, it's actually now it's youtube.com/the current source 555.
Host 2 41:39
Cool. Every day Yeah. So Derek, you want to sign us up?
Host 1 41:49
But yeah. That was the macro fab engineering podcast. I was your guest Eric Brody.
Host 2 41:57
And we're your hosts Sparky Dolman
Host 3 41:58
And Steven Craig. Plein Air everyone take it easy, guys.
Host 2 42:10
Thank you. Yes, you are listener for downloading our show. If you have a cool idea, project or topic that you want Steven AI to discuss, tweet us at Mac Febo email us at podcast at Mac fab.com or comment on a Derek's video on YouTube. Also, check out our Slack channel. If you're not subscribed to the podcast yet, click that subscribe button. That way you get the latest episode right when it releases and please review us on iTunes. It helps the show stay visible. helps new listeners find us
Transcribed by https://otter.ai