The quest for the right connector for a project! The right of passage for any hardware electrical engineer starts with a connector catalog.
This is the last installment of Stephen's 'Adventures in Injection Molding'. We are going to recap the entire two year sage and close the book on it.
The Jeep Prop Fan project rides again! Well some iteration of it at least. Lets design an open source PCM (Power Control Module) for automotive apps!
Parker is an Electrical Engineer with backgrounds in Embedded System Design and Digital Signal Processing. He got his start in 2005 by hacking Nintendo consoles into portable gaming units. The following year he designed and produced an Atari 2600 video mod to allow the Atari to display a crisp, RF fuzz free picture on newer TVs. Over a thousand Atari video mods where produced by Parker from 2006 to 2011 and the mod is still made by other enthusiasts in the Atari community.
In 2006, Parker enrolled at The University of Texas at Austin as a Petroleum Engineer. After realizing electronics was his passion he switched majors in 2007 to Electrical and Computer Engineering. Following his previous background in making the Atari 2600 video mod, Parker decided to take more board layout classes and circuit design classes. Other areas of study include robotics, microcontroller theory and design, FPGA development with VHDL and Verilog, and image and signal processing with DSPs. In 2010, Parker won a Ti sponsored Launchpad programming and design contest that was held by the IEEE CS chapter at the University. Parker graduated with a BS in Electrical and Computer Engineering in the Spring of 2012.
In the Summer of 2012, Parker was hired on as an Electrical Engineer at Dynamic Perception to design and prototype new electronic products. Here, Parker learned about full product development cycles and honed his board layout skills. Seeing the difficulties in managing operations and FCC/CE compliance testing, Parker thought there had to be a better way for small electronic companies to get their product out in customer's hands.
Parker also runs the blog, longhornengineer.com, where he posts his personal projects, technical guides, and appnotes about board layout design and components.
Stephen Kraig began his electronics career by building musical oriented circuits in 2003. Stephen is an avid guitar player and, in his down time, manufactures audio electronics including guitar amplifiers, pedals, and pro audio gear. Stephen graduated with a BS in Electrical Engineering from Texas A&M University.
Special thanks to whixr over at Tymkrs for the intro and outro!
Welcome to the macro fab engineering podcast. We're your hosts, Parker, Dolman.
And Steven Gregg.
This is episode 269. So last week, I was working on that fan controller for the jeep. And this is the product that we talked about, like several different ways to solve the override signal issue.
Everything was like cascading li larger in Project difficult that yes, scope. It was like one step away from just redesigning the whole thing you're saying.
Pretty close. Yeah. So that evening, last week, I opened it up. And what's very interesting about it about the enclosure is it fits everything about it fits tightly together, like you undo the screws, and it actually feels like it's glued together how tight the panels fit fit inside the enclosure. But there's no waterproof seals or anything in it. So I'm guessing it's just relies on it being a tight fit. Because like the the instruction set, you can put anywhere, quote anywhere, like under the hood, and I'm like, well, it's gonna get wet Jeep,
they want it to feel good. They don't want it to rattle or anything like that,
I guess so. But upon opening it, it definitely was not designed by delta pag, which is the company who made the food design the fan, and supposedly manufactures the fan too. They definitely did not design this controller, though. Because a US designer would not use this microcontroller that's in there. And it's a part number G ad F 960. AP, which is an ad 51 core, like generic Chinese microcontroller. Yeah, if you Google that part number, it's like my tweet and like three like Chinese datasheet show up. It does have a dot, dot dot dot matrix, the seven segment display on the front is custom as well. Like they rolled their own, I guess, die, or mold for the seven segment display because it has like all like the bar graph for like how much power you're sending the fan and all that crazy stuff. So I started looking basically the MCU option to like reprogramming the MCU was pretty much off the table because I wasn't going to try to figure out how to make the tool chain for that microcontroller work. Oh, yeah, I'm sure that would be brutal. Yeah,
I'm looking through my phone. Didn't you send me a picture of the board? Ah,
maybe I've not seen it. Whatever. I can post it online. So the next thing I went through his Okay, let's see how easy would be to like just modify the circuit to make it work with a active high signal instead of an active low signal, which is that was the whole problem. The override signal is an active low, not an active high, we want active high because that's how like everything in vehicles work. And so what's interesting about the override signal goes through a diode, and then it's just pulled up to five volts with a 10k and then goes into the microcontroller. So there's nothing like inverter circuit or anything like that on there. And I'm pretty sure that diode is just to prevent back feeding, if you accidentally do put 12 volts on it, that doesn't just completely blow up the five volt regulator by back feeding voltage into it.
Well, is that pin? I mean, is that just like connected directly to the micro
through a diode? Well, that's what I mean. Yes. Okay. So the other side of the diode is just the processor, just the processor. Yeah, it's not like a driver anything. No, no driver, nothing we can like hack there. So pretty much the way to invert the signal hung and do is I'm gonna do it inside the box, but I'm just gonna use like a MOSFET engine on MOSFET to pull down that override signal visible cut the trace inside there, and then put this MOSFET with like a 10k Pull down on the gate on the MOSFET. So then my new 12 volt active high signal goes into I'm just going to use like 100 Ohm resistor to kind of like prevent the gate from being slammed by 12 volts and then have that pull down the five volt signal inside the mic inside the box that's then converts to an active low. And so I put a little schematic it's a simple MOSFET controller or MOSFET inverter signal. So you know
one thing I'm looking at here that might be worthwhile is just on the gate of this MOSFET. Add like a back to back 18 or 20 volt zener or something like that, just in case like large spikes show up on the, on the, on the 12 volt rail such that it doesn't puncture the gate, you know, just yeah, some some added protection. Yeah, it's little TV is on there. Yeah, yeah. And usually these little MOSFETs have, I don't know, something in the 20 to 30 volt range is their maximum gate VGS or whatever. So, so just something a little bit something above 12 but lower than that number. Yeah,
I think I think the I think this one is 30 volts, because it's, uh, I just chose a BSS. 138 Because I have like, sick. Yeah, it's the generic END channel. Or the to end 7000 Yeah, that too. But I got tons of these little guys, so I'm just gonna use him.
Oh, yeah, no, the absolute max gate source voltage is plus minus 20. So maybe maybe like a fifteens. Back to back or something like that. Yeah. But you find especially if this thing is semi critical.
Well over a signal, technically not. But yeah. But you're right. Cool. So that's what I'm going to do to fix it. And I'm probably actually going to spin a little board to make it work. It's dead bugging inside of there.
Oh, come on, you don't want to do what did we coin it the other day, Cthulhu style
through loose out No, I don't want this thing to be reliable. So I'm going to spin a little one sided board to so I can just like kind of like super glued this board down, and then put a little jumper wires off of it, that connect to the board. And then I'll just caught snot the snot out of it should be good,
nice. Um, I'm getting a little bit better at Cthulhu style, I had to do some some Cthulhu today on a new design, because I just needed an op amp buffer. And so just dead booked an op amp on top of another op amps so that I could bend the pins down and just access the power, and then tombstones a bunch of resistors, not a bunch two of them, and just passed everything around and got a got a buffer pretty easily. And if you're you can really only see it if you're paying attention, because there's two op eds stacked on top of each other.
So it's getting better at Cthulhu style mean that it's more organized or less organized,
getting better at Cthulhu style is such that I can hand it to my testers. And they don't comment on it.
They're just getting used to
you Well, yeah, I mean, honestly, like, okay, so I have the choice, I could spin another board and make this simple fix. Or I could just do it really quickly like this and then know that my next Board has been will work. I'll choose this, you know, because spinning a board takes a long time. Oh, yes, it does. Okay, so I ran into a an interesting thing that I've always, I've always heard about it in terms of like people having problems with it, but I've never actually really, I've never had it be an actual issue for me. So I actually had a problem with component crosstalk this week, and I'm talking about internal to a component. Okay,
because I know a while back, we talked about PCB crosstalk. Right, right,
and how to avoid it and things. In fact, I think crosstalk is a term that that engineers throw around a lot when, and they blame crosstalk for things that are probably not actually crosstalk they're just potentially maybe subpar design or a handful of other things. I actually ran into internal component crosstalk and it's, it's such a rare thing in my work, at least that it took me forever to figure it out. And I was banging my head on the table. Because like, I just wasn't able to unlock my mind and consider that that was the thing that was causing this because I started going into that
you have one of those Illuminati moments then Illuminati Sure.
A little triangle I appeared above my head or forehead.
So I mean, the thing is like, okay, so I got into that that problem where you can we see an issue with your circuit and then you start questioning what's causing and you start trying to diagnose blah, blah, blah, and then you then your mind starts to really go and you start thinking about more and more obscure things, then you get into this really dark place. And so okay, I ran into this issue with a tube circuit, not a not a solid state circuit, but this this totally applies in solid State led to the so So here's, here's the situation, I'm building an amp with a buddy. And I have a very generic gain structure in this. And so basically you have an input, it goes into a common cathode or common emitter stage amplifier. Out of that it goes into some some user controls, including a volume control. And then that dumps into another stage. Super vanilla super generic, super, super simple. So here's the the issue that I was running into. If you turn the gain or the volume down all the way, which is basically a potentiometer, that connects those two stages, you're shunting the signal from the first stage to ground such that the second stage doesn't get signal whatsoever. But if you apply an input, a signal to the input, you were getting, I was getting an output from both stages, even though I had my potentiometers shunted the ground, turned all the way down. And it was just driving me insane. Because it's so funny. I've used the word crosstalk a handful of times, and even in you know, at work, not even just my own hobby projects and whatnot. But Never have I actually had it be this kind of problem. And I have to admit this problem is is a little bit ridiculous, in terms of the situation I ran into is not a normal situation. In other words, I had a frequency generator that I was putting into my circuit, I was pumping like a pretty large signal into it. I was applying. I don't know what what 60 times gain to that signal, such that my very first stage in this amp was pumping out like 120 volts peak to peak out of it. And then and then I was wondering why I was getting five millivolts on the output of the second stage. But but so the thing is, though, like if you have the volume down, the user expects there it to be dead silent, right? So what's happening there. After after, like just beating my head on the table for a while, I just realized that, hey, these tubes have two stages inside of them. And they can bleed internally. So those two stages are just next to each other. Just yeah, they're next to they're in very close proximity to each other. One of the stages was useless doing nothing. The second, but the other stage was they're cranking out like every bit of juice it possibly could. So go figure they crosstalk between each other. And it's funny because it made me think about it, like, in so many in so many situations, you just don't run into that. So you see things like crosstalk figures on, on an op amp datasheet will be like 120 decibels DB or negative 120 decibels. And you just like kind of gloss over that because it's just like, okay, whatever. But like that is the thing that actually comes into play. And sometimes you have to be careful about that. So this is just one of those situations where I even called up a buddy who has an amp that has that I know has the same general structure. And I was like, I just need you to fact check me here, turn your volume all the way down and put a signal into it. Do you hear anything? And of course, yeah, he does. And that's on a production app that's on that's on a big company. Like, they just don't care about it. So that's something that I wasn't necessarily, excuse me wanting to design into my stuff. So I ended up just reconfiguring the gain stages such that one of my tubes that has two sections in it, it's only half of basically, I split the gain stages between two different tubes, as opposed to putting them both inside one. So it's impossible for the for one channel to bleed into another one now. But that's I don't know, you kind of made me smile after I was pissed off for like a full day at this thing, because it's just like, why didn't I think about that?
So I got a question. As you mentioned the the rejection to CrossTalk figure that's an an op amp. Yep. You said like negative 120 DB, which is like Insanity. Right?
Like, yeah, yeah. And that's just the number I pulled out of my book. Yeah, no, I
know. But like, is there a figure like that for those tubes?
You know, what's, what's interesting is I've seen that before, but mainly on like forums and things like that. So I don't know exactly how accurate it is. What you do see more often is capacitance, like a capacitance between two channels. And then depending on the impedance of your channel, you can sort of back calculate what you might see on the other side. Yeah, what kind of coupling you'll get. Yeah, yeah. So The answer is no. But I can tell you this. It's not it's not particularly good. But it's also not. It's, I've only ever run into it now. So let's just put it that way, you know. And like I said, I was putting a massive signal into the input and 100 volts or 120 volts or whatever on the first section produced five millivolts on the other section. So you I guess you could back calculate what that crosstalk is right. But in other words, it's not much. But the thing is that five millivolts, that comes off the other stage gets amplified more later on, will. But no, there's more preamp gain after that. So it does get amplified enough to be audible. So that was the biggest thing is like, in thinking about how the user interacts with things, will that confuse somebody if they have, if they turn their volume all the way down? But they yet they can still hear something? And the answer is, yeah, of course, it'll confuse them. That's why I checked with someone else who has something out there. And that's using air quotes, normal operation. But like I said, I had I have a solution that should just demolish that altogether. Only problem now is, it's traditional to have two adjacent stages next to each other in one, two backage. because there'll be out of phase with each other. So you don't get positive feedback. But if you start sharing between even numbers of stages, there's a chance you'll get positive feedback in and so then you have chances for oscillation and things like that. So I'm giving some other stuff a try right now, but having to see what's the result of potential oscillation feedback. So, you know, when those when those figures are on a datasheet, they actually do mean something. And this can not can this certainly does apply in the solid state realm in op amps and things like that. But, you know, you're not usually talking about ginormous signals. Like 120 volts?
No, not yet. Well, yes, I guess it depends. But, yeah, for most most microcontroller or low, low or solid state stuff, you're correct. Yeah.
Yeah. Yeah. In fact, I'm just curious now. I want to know, what is the crosstalk figure for a tl 08 For between the four packages inside? What is it going to be? Because I mean, the basically the, the largest does what you can you can run a deal aid for on 36 volts. So you can expect something around say 30 volts maximum signal, if you wanted to just juice A DLA for? So I guess I should have been prepared for this live readings of data sheets
is exactly what everyone wanted.
Yeah, okay. We're not sorry. That's common mode. Oh, crosstalk crosstalk attenuation it says 120 decibels. That's virtually nothing. Right?
exhalation see what the DB reduction reduction was to
go to google and type dB, two decimal.
You said that it was point. You said what, five millivolts? Out?
Oh, yeah. 100 and 120 volt peak to peak in five millivolts. peak to peak out.
So that's like a 2400 reduction. Like ratio, which is like, what negative 70 know, like negative 65 DB? Something like that? Sounds about right. Let's see. I'm just looking at like a decimal, the voltage gain loss converter chart, and it's somewhere in there. So that's not terrible. No, it's not terrible. It's it's half as good as the theoretical op amp that you said. Theoretical. What was the the op amp? You just looked up? What
was the DL? 084? Yeah, what was the Oh 820 decibel is what it says crosstalk attenuation is.
Okay. So you were actually correct when you say 220. So your tubes are a little bit over half as good as well. half as good in a linear sense. But DBS is logarithmic. Right. So actually, that op amp is insane. Compared to Yeah, comparatively. Because what if it was? Yeah, yeah, because it's logarithmic yet, so it's not half it's like a quarter. That's good. Something like that
10 to the Yeah, 10 to the negative six is the voltage ratio for crosstalk on those topics. So that's pretty good. In other words, like, this is probably why I haven't run into this before is because like, we're talking about low voltages, and then insane crosstalk. So the only time I ran into it is when I put a tube in a really ridiculous situation and just used it, you know, yeah,
I'll say it's the tubes not handling 3.3 volts, it's handling 120 volts. It's still only point. Oh, five volts out,
which is oh, five. Yeah, but it was still enough to get signal through, which is annoying.
You could just put like, a double game potentiometer that turned that stage down to that. I'd
seen that. Yeah, no, you totally can. Well, and there, okay, so there is another volume control later in the app, like down the road?
So is it called Super volume? Well, the
first one is called gain. And the last one is called volume. Okay, right. So once again, this is another situation, that's kind of ridiculous, where the only way you could hear something is if you have the master volume, ie the one later on down the signal chain cranked all the way up. And that you had the first volume, the gain knob turned all the way down. That's the only signal and you had a massive signal going, Yeah,
massive input signal. Like, what is a mat? What signal were you putting into it?
I had, I had just like a one kilohertz sine wave that was at one, like one and a half volt peak.
So what So this is a I'm gonna assume this is a guitar amplifier. So what's a normal guitar signal like?
Well, that's a really hard thing to answer, mainly because a regular guitar signal is all over the place. Are you strumming? Are you picking single notes?
Are you like if you were going like Eddie Van Halen at the guitar? Full on how how big of a signal? Could you push out of a guitar.
So like, with the hottest pickups and like, like just strumming your face off, you might get like two volts, two to three volts peak, something like that. Okay, on the initial transient when the pic strikes the string, like I've seen up to four, okay, so four, four volts, but as soon as like, it decays off and you're sustaining, it drops to like, one to 300 millivolts something like okay, so that initial hit is huge, but ish, like so I have two guitars on one of them. It's like a volt and a half or something like that. And on the on the other guitar, it's like, half a volt for that initial strike. So I was being unfair, but I was also trying to break my circuit and see like, where are all of its failures?
Yep. Like a good engineer. No, of course. Yeah. So hit a tar revision for has hit the house. Oh, bump on Oh, it's red. It's red. Maca Feb red.
Yeah, the the logo on the back is cool.
Yeah, and so yeah, have the Patar logo on the back but that is changing. It's going to have something special on the back.
Oh, did you hire an artist to do something? Maybe
he's talking so I stood out through the through hole on it. Basically, I'm waiting for Mouser to like have a box show up tonight. And then I'm gonna start soldering like crazy because I got seven boards that populate through Hold on. And Mouser and DigiKey are like Delaine shipments right now.
Oh, yeah. So and by by delaying like I just got a Mauser shipment in but by delaying like, it's the normal like three days shipment is has like six now.
Yeah, it's not too bad. No, it's not at all. And then I got a built boards for the the production LED boards. So I added a little tag connect to them. So I can easily spot check if the LEDs are good. Instead of having a plug into like the locking JST connector, I can just put a tag connect on and the tag Connect will send five volts ground and the communication signal.
So actually, a partner and I were talking about that a little bit earlier, the Tech Connect thing. So basically, you're just using that to test all of your little LED boards, right? Yes. So um, Curious, do you just do you have like a script that's talking to the TED Connect? Or I guess an st link or something like that? Or how are you actually, like you're sending data through? Oh, yeah. So
it's a, I have the boxes. And basically, I just, I'm, I have a box that's got a nine volt battery in it. It's one of those project boxes with nine with a battery compartment. And then there's just an Arduino Nano in there. And then you press a button that powers up to Arduino Nano. And then it just spits. It basically just immediately starts spitting five volts out on the technic in the communication. So okay, is it just like continuously dropping, just like it's just spitting out communication such that you can hot plug it in, and then it just lights up, plug it in, and it cycles between white, red, green, blue, and then goes back to white? And cycles? Those three or four?
That's a really convenient way for testing arrays of boards. Yes, see, I
mean, you just plug it in and look. And you're done. Yeah. Ease login. And look, make sure it's cycles, all the colors, and then you're good to go.
Actually, if why even do all three colors. If you have white, then isn't that good enough?
Well, so you might actually I was actually talking about not even doing white and just doing red, green, blue. Sure. Because the main thing is making sure all the intensities are there. So because you could have like a week blue, or week green or week red, and it will still look white in color. So you're correct. You could just have white, but then you have to like Okay, is it a cool white? Is it a warm white?
Yeah, you're right. If it's just 100%, red, green and blue. That's a lot easier to check. Yeah.
So yeah, hopefully, next week, I have an update on or in two weeks, I have an update on like, making sure like the Penetang is like production certified in quotes. So you said you're building seven of them, right? Are these gonna go in some machine, they're going into some machine one staying with me for hardware validation. One is going over to NPF, which is mission mission pinball framework, which is a open source project to do like the high level code side of pinball platforms. And so they that is a really cool community and a really cool piece of software, where basically you can like, script out your pinball machine, the code, and then all you have to do is change the header file be like Pinots or, or I want to do like, fast pinball, which is another platform, like all you have to do is just change the header and then like, it just works. That's it does all the glue logic for the high level to low level. So it handles like sound and audio visuals and that kind of stuff. So are you providing software support for your boards? For only for the firmware? That's on the microcontroller? Right, right. And is that what so what you do is this, you plug this board the printer via USB into your computer, and the computer is running the pinball software? And then the pinball software is telling the board Hey, what is what are these switches, sudden these lights, that kind of stuff? You know, I'm sure kind of like the CNC controller, where you have a PC that's actually running the G code and doing all the high level stuff. And it's telling a CNC board, you know, the CNC boards handling the moving the steppers around. Think about like that.
I I'm pretty sure I've asked this question before, though. There's, is there like on the computer side of things where they actually write the game, I guess, are they're like, unified codes for like, this is a flipper. This is a light, this is a blah, blah, blah.
It depends on is a couple of different high level stuff, but mission pinball frameworks like that. Yeah.
Got it. So this week, you think you'll have a handful of them running?
I hope so. Yeah, one goes to the MPF because they have an older prototype, and I want to get like a production ready into their hands. And then the rest go up to Wisconsin. Thanks. So should be pretty good. So this is a question that has been on our list for a couple of weeks now. We just haven't gotten to it. And I don't know what actually because this is a question that Stephen wanted to ask. It's and I'm actually really curious what what caused this?
Well, okay, so to to 2010. I think 2010 Maybe 2011. I did an open source PCB.
Okay, you talked about the year
2010 Yeah, the year 2010, I was a year out of college. And in my first apartment, I just cooked up a PCB design, go figure for a guitar. And, and I posted it all on a on a forum. And it was I was actually way more than just a PCB, because it was like custom transformer specs, it was a full chassis design. It was like the whole system, it was everything. I provided it all. And I built one. My buddy built one. And then on this forum, there was probably at least 10 other people who built them. Oh, that's really cool. Yeah, it was it was it was awesome. I got the board's made a handful of other people at their own, and stuff. And what was what was interesting is there was one individual on there that we kind of, I kind of helped them out with a handful of things. And he never actually finished, they that that thing, we'll fast forward to, like, a few weeks ago, I get a message on the forum, which, by the way, like, I don't really go to that forum much anymore. I go every once in a while just look at stuff. I just randomly stumbled upon that forum and saw that I had multiple messages from that. That one guy who didn't ever finish this project. That was it was a lot of it was kind, but there was a lot of, oh, this doesn't work, I need your help give me some help. And I'm like, Dude, this is like a decade old. I don't even have the files anymore. I don't even remember it. I've actually rebuilt that thing, redesigned it and rebuilt it twice since then. So I don't even remember what those original files look like. I pulled the original files from from Google because I didn't want to support them anymore. This was well before GitHub was a thing. So I had like a Google share thing going on where people could request access to get these files. And what's what's really funny is that this guy did actually solve all of these things, even even after sending all of these, like, I need help, I need you to support this project from a decade ago. And he sent me a nice message saying like, Oh, I just found that there was this one issue with my board and replaced a handful of things. And it works out well. And even put up like a YouTube video, I think of him playing on it, which was cool. But it got me thinking was like, how, how reasonable like what's a reasonable timeframe that somebody should support their open source design? And what's reasonable in terms of like, not demanding? What is it resources or asking for support on it? But like, what's a real? Like? What's reasonable to ask the original designer? On?
Yeah, it? It really depends. On that second question. It really depends on like, what if it's a single person running the project? Like I, my expectation, for me, at least is zero?
That's a good one. Yeah, that's great. Because
it when it's just one person doing a project, it's their hobby. Majority time it's their hobby. And asking them a question is usually okay, but demanding or expecting an answer is usually not the right way to go.
Yeah, and I hope I didn't paint this guy's like a jerk or anything like that. He's actually super kind. But like, the phrasing that that was using there was like, I must have your help kind of thing. And I get he was, perhaps a little bit frazzled. In asking for that. But it was also like, jeez, like, I'm lucky that I logged into this old forum, just to see and there was a message for me on there.
The, I guess it might be also be, I kind of view open source stuff, especially open source hardware, a little bit differently than some people do. I view open source hardware as a way to figure out and learn about a project and how it functions so I can incorporate that knowledge and someone else's techniques into my ideas and projects. There's a whole like, we can go down the rabbit hole of the whole idea of like open source is for cloning, and for driving down PCB like hardware costs, which is one way to think about it. From a designer perspective, I don't like that idea. We might get some I might get some hate mail for that one. But yeah, cuz because when you think about it is you like let's, let's rewind the clock back 11 years to when you were doing that Were you expecting to make any sorts of money on that project?
Oh, I lost a ton of money doing that.
That's so it's a it's a hobby.
Oh, it was 100% a hobby? Yeah, yeah. No, I mean, I wasn't even expecting to, you know, spend spend money doing stuff but but there was there was some regard I had to ship transformers to overseas, you know two guys who had them. And that was great and all but I SPECT transformers, they cost a bunch of money, people paid me for them. And then the Transformers came in and they didn't have dual primaries. And even though I had SPECT dual primary, so I had to fight and duke it out with the transformer company. And they ended up you know, doing a whole nother round of transformers, but on my dollar at a significantly reduced cost kind of thing. But I had to eat that because no one on the forum wanted to pay extra because there were like you said it was coming with dual primary. So basically, to make sure that like I was in good standing on the forum, I ate a couple 100 bucks to make everyone happy. So yeah, garbage. Yeah, that's unfortunate. Yeah. But I mean, I ended up with like, 10 transformers that I use for other. So I got a bird cheap guys.
Yeah, I don't know. Um, in terms of Statue of Liberty. Statue of Liberty.
Liberty. Limit? Yeah. Yeah.
limitations. That's the word I want. On a project? I would say. I would say a couple years, three years, I think. Yeah. past that. It's kind of like, it's dead.
Well, and also Okay, so you have to look at okay, yeah, right. So if, say it's three years in, and you see that that user is super hyperactive, in whatever place they're at be at GitHub or on a forum or something like that. Maybe it's longer than three years. But if you've, if you see that that thing that if the last conversation about that project happened years and years ago, like, that's a good indicator that it's probably not supported.
No, no, no, I totally agree with you on that. If it's, if it's the person still talking about it, or if people are still using it, then yes, I would say it's, that's the point when it goes cold. When the project goes cold, then it's like, Okay, three years later, that's when when if you need to use that, that project, and there's a problem you need to solve. That's when you fork it and improve upon the project, use that project as your initial knowledge base, and learn and grow and make that project better and contribute. That's contribute. That's that's the key word in open source that a lot of people don't seem to grasp. I attributing I think
I think I mean, 100% agree, I agree with you on that. But I think that there's a problem in open source world, where people think, Hey, there's this thing on the internet that if I just follow these instructions, then I get a thing that does everything I want it to, and it works. And that's hardly ever the case is at least in my experience, I think sort of going on what what you said earlier about, you know, there's there's some expectations with open source hardware specifically, I think that one big expectation that should be there is that you're you're building this at your own risk. And if there's problems you should be the first thing to see what the problem is. In other words, if you turn it on, and it doesn't work immediately you don't instantaneously go to the original designer or the forums and say what's wrong? Like it's a kind of up to you to go look and figure it out, you know?
Yeah, it's this might sound weird, or maybe not weird, but it's something I've noticed on like Arduino forums and stuff, people will buy like clones of boards and then wonder why stuff doesn't work. And it's like, you know, you're putting a lot of onus on something that you like, didn't give money or effort into into the community. That's why like, I will buy I only buy like legit Arduinos and stuff like that because when I go to like arduino.com for or CC or whatever it is, now I want to have that dust ever settle between like the two Arduinos of the world? Well, I don't remember the we've talked about that a bunch Gen Duino which is like the genuine
one Oh, genuinely No, yeah, yeah, yeah.
And that's a whole nother rabbit hole like I could probably even forgot about that. We talked about on like an episode long time ago. Yeah. It's like that. But that is why I will buy the hardware because I know I'm not going to be able to contribute to the open source software side, like the IDE, or the libraries, I won't be able to contribute to that because I'm not. In my mind, I am not good enough to be able to fix bugs in that software. There's way better developers and programmers in the world that will work on that. So what how can I give back? And is by buying the official hardware so that they have money to build support the forms and build support, hardware development, all that good stuff. And so when you take that away, if you buy clones, then what do you give back to the community? You had to give back in either software or something like that? I know if you're just beginning out, it's buy what you want to buy. I'm not going to tell you otherwise. But it's that's just in my mind, is I view open source as a community driven and emphasis on the community and giving back to it. You don't have to give back right away. But I plan on doing it is a good way to do it.
Or if you know the answer to somebody's woes, question, yeah. Yeah, answering questions.
Yeah. That's a huge part of
it. Yeah. And you never know, you may be that guy who has the answer to something where someone's searching like 10 years down the road? And they found your answer. And that's exactly what they needed to get exactly what they needed. Yep. That's a Stack Exchange, like every day for a bazillion people.
Yeah, I don't know if I'll catch flack for that. I that, that thought process on it. But because I know that stuff is really polarizing. It is very polarizing. It's for a while we like you. And I kind of just like stop working in that space. I kind of stopped building hardware that's open source, like pin hack was an open source hardware project. And we had a we had a group of people that decided to say, Oh, we don't care about that license. So we're going to steal all your stuff. So that was a lot of fun. So that kind of put a sour taste, I guess, in my mouth for open source stuff from me doing putting a lot of effort into and then someone just going, I'm going to clone that.
I mean, what kind of enforcement is there? There's none. Right?
Technically, since they broke the license agreement. I could bar them shipping them into the United States, but they don't ship them into United States. So it's like, I can't do anything.
I mean, what would what what governing body recognize your license? Agreement?
Customs, US Customs? Yeah, it goes to us, because then they're violating the open source license, because they violated the license I had on it. So it would violate copyright. But what I'm saying is good. You write that license, or did you use like a can I use a I use? Creative Commons? 4.0? Blah, blah,
blah, blah. Okay, so if you wanted to pursue it, you could, but it would just be a huge time and money wasted?
Well, the only thing I could really do, because it's a group in China, the only thing I could really do is bar them from being able to sell them basically, in the United States. Our
boards even look similar.
No, they don't. Okay, but that, but the circuits, probably I almost just circuits are 100% identical, really? What are they? Like? I didn't know. And they even they even ripped off like the code? Because like, oh, because you both had some of their? What was that? Well, I mean, it was all up there. Right? Well, they use an older version of the software. And that we because we stopped putting the code publicly as well, because we noticed this group was stealing stuff. And that's what it's called people. It's theft. If you break the license, it's theft. And so they were using in the like, they had a bunch of workarounds because we fix some low level stuff that like for like updating the firmware and stuff on the board that they couldn't have and they were using, like, so Ben Ben heckendorn did like the low level code for like, the Tet for the text driver. It goes on to the screen. And he used like, a modified like Atari 800 font. Okay, like he took the Atari 800 font and like modified it to make it work on dot matrix display. So it's like, no one would use that font because we custom made it.
They had that font So that yeah, they stray.
And we were using a parallax propeller and a pic 32 as our two microcontrollers, that propeller was used during the audio video, and the pic 32 was doing the low level like solo drivers and stuff. No one in the right mind would use a parallax propeller for what we did before. And it was all assembly code to make it run fast enough. They had the same architecture, and they wired up all the parallax propeller stuff exactly the same
way we did it. Yeah, well, so yeah, exactly. Copy. It was
the schematic was a direct clone. So, yeah, that was not a good time in the pinball world, I guess for that. So actually, because of that whole experience, I kind of stopped doing open source hardware Pignataro, or is the schematic will be open. But the for the hardware will not be? I'm curious why the schematics gonna be open. So it's easier to for people to fix.
Okay, gotcha. And this is
how again, goes rolls back to how I view what is important in a circuit for what is important to learn from a circuit and open source. Most of the time, it's not the layout. It's the schematic how does that circuit function. Now, sometimes the layout might matter, like if it's a switch mode, power supply, or are some, you know, analog voodoo, front end stuff that the routings very important for. But this, the pinto is 100%, digital, there's nothing that is like non reference design in the layout. It's just all stitched together. It just all stitched together. But the thing is how it's stitched together is through the schematic. And so how the schematic functions, that's where the where you learn it from the penetrator, if you were going to learn something as a hardware designer through the penetrator, it'd be by looking at the schematic the layout is nothing special about it. So, again, the only thing about putting the layout out there just makes it easier for someone to clone it. Putting the schematic out there. Okay, someone's actually got to at least designed the board at that point. So, and I know it's like, oh, you know, someone could just Depop the board and scan the layers. And yeah, you can do that. But at least I got 200 and whatever dollars for selling that board. Right? Right. So that person gave back to the maker, at least.
Okay, try not to sound like a stick in the mud or anything about it. I love open source stuff. I get to learn so much about other people's designs. And, you know, I mean, that's how I, I didn't learn layout from college, I learned layout on my own looking at other boards
on a present. So, so, three years seems like the right amount.
To answer this long winded question, went down this rabbit hole. Yeah. I'm actually going to be really curious of what people on Twitter in in our Slack channel will say about this question. and whatnot. Where are they? What side of the aisle so to speak in open source hardware that they line up on?
00 years is not good enough. And Infinite is too much. So something something in between those two numbers is the right number. If
Yeah, yeah, somewhere in there. I would say three. I think that's reasonable. Yeah. Because after three, if it's been dead for more than three years asking that person, that person probably doesn't remember anymore.
Yeah, like, I don't even have anything anymore. I don't have any of the design files. I don't have anything from what I was asked for. So it's just I'm picking through my memory.
Yeah. And 10 years is a long time to pick through your filing cabinet in your brain.
Oh, yeah. I mean, that yeah, that that project, that project work. I mean, I like it was fine. I would never do it that way again. I mean, I've learned a lot and in over 10 years, it was it was totally fine. For the time and the way I designed it was the way that everyone was doing it at that time. It's just a it's a different flavor of how they were doing it. So everyone was fine with with the way the design worked. But like I said, I would never do it that way again, and I kind of shudder thinking about how I approached a lot of those design aspects. Just labor. It's labor intensive building and I hate that nowadays.
Oh yeah, that is right. A lot of your ideas that you share on the podcast and in terms of AMP design is like, how can I make this lazier?
100%? Yeah, as I'm getting older I want to do if I see a wire, I get mad. I don't want to wire anything anymore. I, I don't mind soldering components. I love soldering components. That's fun, but I hate wires. So the less I have to strip wires and solder things, the better.
Alright, we got one more topic for today.
So, surprisingly, I have an automotive topic to bring up, which is normally one of one of Parker's things here. But just an interesting note. I think the automotive industry has taken a shotgun blast to the gut in the last year or so. So the a 300 millimeter silicon line from Renesis. How big the wafers are, yeah, that's the wafer size. So yeah, three wafer in a millimeter line from the Renesis factory in Japan, the NACA or na K, I don't know how to pronounce it, but caught on fire last Friday and has gone down. And apparently, it's they're talking about upwards of a month or two before they start, like piecing everything together and getting it back up and running. The thing about this is two thirds of everything that came out of that factory was automotive ICs. And it's Oh, no. And so they're already reporting that both Toyota and Tesla used things that were manufactured at this facility, and they're gonna start seeing delays on things because of this. And it was part of the electroplating section of the of the factory. And so it just seems like, it seems like the automotive industry can't get a break right now. And I mean, we've been talking about this for how long now? Have you a few weeks?
At least two months now? Yeah.
So nothing, like not a whole lot more to say about that. It's just I chunk a little a little bit, but I'm also a little bit heartbroken that that another ice factory is really going under. But the good thing is no one was hurt in this. It's just a large portion of the factory was burned. I thought sucks. I think we have we have some there's some shit in store. I think I think the the US economy and automotive is we've got some stuff coming down the line. Let's just say that it's not, it's gonna get worse before it gets better.
Yeah, supply chain is getting really ravaged right now. Electronics. Yeah. And it's, it's, it's not because like, it's because Well, it's because consumers are wanting to buy a lot of stuff. Now. The man like the man is going crazy. And then on the supply side, one of the suppliers for like six months into anything last year, like didn't prep at all, because if all everyone else was shutting down their orders, because you had all those automotive companies shutting down their orders, saying, Hey, we're not we're going to cancel all our orders six to eight months out now. And so now you have all these component manufacturers either going out of business, or having to get rid of everyone all, you know, all their technicians is up because they can't. They're not selling anything. And then you have then basically, you know, eight months later, everyone's cranking those knobs back up. And then the component industry is just like, wait.
Yeah, there's there were we're starting to see that that droop, that that the recovery is out of phase with the with the request, right? So yes, it will come back, of course, but we're seeing that droop.
So we'll probably see similar to what was the 21 was like the capacitor stuff that was like 2017 1718 Yeah, we're basically how component manufacturers fix that problem was they didn't build new lines or anything, they just consolidated a lot of product lines, which they should have done anyways because there's a lot of redundancy and a lot of product lines. Probably we'll see the same thing here is we'll see a lot of manufacturers moving away from their really inexpensive stuff and going towards more the high margin stuff and just kind of obsoleting a lot of their old stuff. So you might not be able to get those pics sixteens anymore.
How are you going to make clones of Arduinos if you can't get the cheapest
the 80 Mega 320 Oh no. Who knows? i Okay, I bet you the fact that you can buy cloned Arduinos for cheaper than you can buy an 80 Mega 328 P I'm going to throw them all in there and say those 80 Mega 320 EPS on those clones are probably not real at megachips
with that Illuminati moment that was the Mac fab engineering podcast. We were your host, Stephen Craig. Later Everyone, take it easy
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