MEP EP#116: Standard-ish

Podcast Transcript

Host 2     00:11

Welcome to the macro fab engineering podcast. We're your hosts,

Host 3     00:14

Parker, Dolman and Steven Gregg.

Host 2     00:15

This is episode number 116. So before we start, we got Twitter chat, again is April 20, Friday at 1pm Central Time. We haven't really come up with a topic yet. So we'll come up with one and tweet it out when that's all, you know, ready to go. Meetup information, May 23 at 6pm at macro HQ in Houston, we will have Brandon strap from strat room. I hopefully that's all set room set room from particle. He's going to give a talk about IoT fundamentals. And I think we're going to do like a couple episodes of the map with him as well.

Host 3     00:54

Yeah, you might be seeing some pretty cool collaborations that extend beyond the macro fab walls.

Host 2     00:59

Yeah, so that's gonna be pretty cool. And then the Houston hardware the first use and hardware happy hour is coming up soon. It's gonna be the first Thursday of the month, which is May 3. Come by bring hacks and or Hangouts. It's gonna be at slowpokes in Houston. It's going to a place that has beer, coffee and food so should be pretty fun. I haven't actually been there yet. I probably should go and ask them if that's okay.

Host 3     01:25

You know, I was actually over there just the other day and what was cool was it says no electronics. Zero electronics. No, no, here's how I know it's a very like friendly place for electronics guys. You go to pay and write a by the counter just to the right of it was a piece of paper that was like duct taped to the to the counter. And it was a d&d signup sheet. To play d&d ad slowpokes. I was like, okay, these guys are cool. Alright, sounds good. Yeah.

Host 2     01:52

I so yeah. So those are the three events coming up. Oh, will when this podcast comes out. We've already done this month's

Host 3     01:59

Meetup. So Right. Yes. Oh, in the slowpokes Meetup is at 6pm. Yep. Okay, yep.

Host 1     02:07

So Steven, what do you been working on?

Host 3     02:10

This week? I just want to talk real quick about a little bit of a an oscilloscope hack? Actually, no, it's a little bit of a trick more than a hack. So dynamic signal analyzers. Yeah. Have you ever played with no support plane on it? Okay. dynamic signal analyzer is basically a nice big fancy box that will automatically make a Bode plot on a screen for you. And for those who don't know, a Bode plot just basically shows the amplitude response of a system

Host 2     02:44

Filter. Well, oh, yeah, whatever you plug it in. Yeah, I guess. Yeah. Right. It's really a filter. So I guess the system would contain the filter. So right, right. Yeah.

Host 3     02:53

So so the way it works is it spits out a signal, and knows the amplitude that it's spitting out, you put that signal into your circuit, and then it reads the output. And it compares the amplitude of what it's spitting out to what it's reading back. And that ratio, it just prints it on the screen based off of what frequency it's at. So you can tell it to sweep from one frequency to another and display that on the screen. Basically, that shows you the response of filters or amp fires or whatever you want. So you know, the last couple podcasts, I've been talking about a kind of filter that I was working out. And instead of doing things the traditional way, I wanted to get kind of like sudo make a dynamic signal analyzer, or kind of utilize one, but they're usually typically expensive, and I don't want to go out and buy one. But luckily, there's like a cool trick to convert your oscilloscope into one.

Host 2     03:45

One weird trick that test my test manufacturers will hate

Host 3     03:49

Yeah. Agilent doesn't want you to know it. So this trick doesn't really get you like high accuracy. But it's really great for what I was doing because I was making a variable filter. And I just wanted to see that my variable filter was working. Yeah. And so like if you want to just see that what you've made does sort of what you want, this is a great trick for that. So you know the the scanning on an oscilloscope is set by the time base. By turning the time based knob you control how much time it takes for the you know the beam to cross that screw with knob the witness? Yeah, exactly. So the the, the time base is the is the amount of time for each square on the on the whole length of an oscilloscope and mine my oscilloscope has is 10 by 10. And I think that's about what normally that is except the digital one here at macro fab has a widescreen. So it's like, I think it's 210 by 14 Or Well the

Host 2     04:47

Thing about modern one two like that it will just display you can just make it display the information you want to like you don't look at the that's the thing about the time based stuff is. I bet you most students don't even know what that means. Yeah, cuz that's why using the cursors. And yeah, use the cursors. Or like you just read the numbers that you met are, the scope is just measuring, like you can add the measurements. That's why I said the width knob. on base, it's a time base. Because most people still don't use an old school analog scope

Host 3     05:18

Or anything like that. Analog scopes are awesome, because they're so easy. Oh, yeah. So

Host 2     05:23

Use a I think it's for 400. Tektronix.

Host 3     05:28

Yeah. Oh, the 4000. Right. No, no,

Host 2     05:31

This is my old 100 megahertz analog. Oh, not your big like beefy guy. No, no, no, this is a this is all analog can't remember what it is. It's not Tektronix. either. It's what was before it.

Host 3     05:43

There was something before Tektronix? I don't think it's called

Host 1     05:45

Tektronix. Tech something now? I can't remember. Okay. Oh,

Host 3     05:50

Cool. Yeah, well, the the time base knob basically determines how long it takes for the beam across the screen and effect. So if you if you go and create a frequency sweep, which there's some great websites that allow you to create wav files that have a frequency sweep, that has the exact same time base as the entire sweep of the oscilloscope, what you can basically do is trickier scope into showing the sweep signal across the you know, the entire screen basically. So I found a, I found a website that will automatically create a WAV file for you, where you pick the starting frequency, you pick the ending frequency, and you pick how long it takes for it to go from the start to the end frequency. Gotcha. So, so what I did was I just picked like 50 hertz as my low end, I pick 20 kilohertz as my high end. And I told it to go in between those at a rate of like, a 10th of a second or something like that. And if you put your time based on your scope as a 10th of a second, then what you end up seeing is, or what you end up having as the input to your circuit is a sweep between those two frequencies that matches up with your scope. So if you read the output of your scope, or if you look at the time base, you can actually see how the system or the filter will affect the wave. So basically, you just look at the amplitude of the wave, and it will follow the path of what the frequency response will be. So you know, if it's a if it's a low pass filter, it'll it'll be flat out into, you know, however far out it goes, and then you see it trail off. And so with my variable filter, I could, you know, in real time see the frequency response on just, you know, my scope, and all it took was downloading, you know, a little wav file off the computer. So there's tons of YouTube, like tutorials on how to do this. It's not particularly hard. But it's a cool little trick that you can, you know, if you need just like a real small amount of frequency response analysis, and you don't want to spend the $500 for a used, you know, signal analyzer, that's even, that's something on the low end. That's way on the low end. Yeah. And actually, so the thing is, a lot of scopes are actually including this feature now. So you know, how a lot of scopes have FFT? Yeah. Which the fast Fourier transform is not the same thing as as a correct if the fast Fourier transform shows the frequency content of an individual wave, whereas a signal analyzer will show what a whole system does to an entire spectrum of waves. Yes. They, they, they, it's funny, because the plots look similar, they show actually the same, the x and y data are still the same. It's just they do very different things. Regardless, a lot of scopes now include a function generator that has a sweet capability. In fact, I was watching a Tektronix video earlier, where it will actually physically plot a bowtie plot. Hi, it's nice. Yeah, super nice. Because it's like, why go buy a whole signal analyzer thing, when you can just put that into a digital scope nowadays, you know, it's, it just makes sense. So I guess that that trick was good enough that now scope manufacturers are kind of including

Host 2     08:59

Yeah, just added it into their software package.

Host 3     09:00

But it's really nice with what I was doing. Because like, if I wanted to see, hey, is my thing actually notching? I could see it like scope out, like a chunk of the scope, like the way I'm there. So and you could, if you really wanted to, you could put like vertical, one of the column indicators, and actually measure voltage and things like that. It's not going to be super accurate. But if you kind of want to find a general range where your negative three dB point, your cutoff frequency is, you could get like an all ballpark range. Just as an idea, it's way more of a visual thing. Yeah. Basically, it's like, is my thing filtering or is it not more than that?

Host 2     09:39

Yeah, that's a lot of times I use a scope for is just visual stuff like, oh, is my ripple in the right area, it needs to be for the power supply and stuff like that. That's because I'm more of a digital guy.

Host 3     09:51

Well, yeah, but you know, this is a little bit more of a trick that if you ever need to do frequency response and still feel like just seeing, you know, something works, is it good? little trick for it. So

Host 2     10:00

Yeah, so I looked at it was it still check Tektronix back then it just they changed the logo, your little scope? Yeah, it's like a 464 or something like that. Ah, gotcha with the screen in the middle.

Host 3     10:12

Oh, it's green. It's not the circle screen. Is it? No, no, no, it's a

Host 2     10:16

Rectangle. Okay, okay, or square or whatever do channel get to channel nice. The problem with it is it's got a weird transistor issue that once it heats up, it stops really working too well, like the beam stops. And you got to pick it up and drop it

Host 3     10:30

Like an inch. And then I'll start working sure that the transistors should not like just a soldering as well. I've

Host 2     10:34

Tried actually might be I tried unconnected and everything and reconnecting everything back in it. Still hasn't really fixed it. I need to sit down. I think when they industry solder everything. And Dell HP I fix it.

Host 3     10:45

That's that's probably, I'm guessing that's a six pack worth of time. Yeah,

Host 2     10:50

There's a there's like 50 boards in there that he saw.

Host 3     10:54

You know, I was looking on eBay the other day, and there's a lot of oscilloscope rebuild kits. Maybe I should do that. Yeah, I was actually looking for the scope that I have. It actually needs a lot of love. It has some issues with the triggering system and all kinds of crap. But regardless, there was a kit that was it was 70 bucks, and you replace every transistor in it and every capacitor in it and a handful of resistors that when it was built, they didn't put high precision resistors and now these are high precision resistors so the thing that sucks is like, yeah, you spend 70 bucks on it, but then you have to calibrate it. Yeah, you'd have to Yeah. And and I looked at the calibration for my scope. And it's like, it's seriously like 60 pages of, of calibration stuff. And, and some of the calibration stuff is like, it points to like five different trim pots. And it's like, mess with these until this happens. And it doesn't really tell you what each one does. It's just like good luck. That's a

Host 1     11:48

Total gray beard. Oh, yeah.

Host 3     11:51

Yeah, for sure.

Host 2     11:54

The thing about that Tektronix, though, is I really only use it for visual stuff. Because I have a Tektronix like TDs 520, which is a 500 megahertz scope. Yeah, it's a, like analog fronton with a digital readout on the CRT. Right. So it's actually really nice. So you get some of the modern stuff of like, oh, the frequencies 100 kilohertz because it will actually display it. Right. And you can you have like measures and you can actually measure stuff. The fact that they did all that in a raster beam is pretty crazy.

Host 3     12:25

Yeah, it there's a there's a lot of extra circuitry just just for that stuff. Yeah.

Host 2     12:31

And that's a really nice scope when I just want to like look at like, especially like audio stuff. Or if I want to look at like a low frequency like filter or something. I'll just use that because I just have to plug it in and just wiggle the knob a couple times until the it looks correct. Nice. So

Host 3     12:50

Yeah, so this scope I have I love this, it has like an extra gravy or mode on it. Like so mine, mine has like the beam on it like your standard beam. It's an old analog scope. And it also displays the digital information is not is nowhere near as clear as yours. Because yours is more of yours has a different screen on it's not like yeah, it's not the same like green CRT. Yeah, it actually shows it's a white screen, right? It's a white screen. So mine isn't the classic one. So it shows both the beam in analog, but then it shows a bunch of digital information on it. There's two separate knobs to control both the beam and the digital information, their intensity. So if you want, you can turn the digital stuff all the way off. Gotcha and have like, original gray beard. stuff within then you'd have to look at every single one of the knobs. Yeah, and say like, oh, I'm at five volts per division and a time base of this, because it's still written there. But I never read those knobs because it always displays in the in the digital form. Yeah, exactly. But it but yeah, you can you can you can turn that off. Yeah,

Host 2     13:52

Actually, my TDs 520 doesn't have stuff on the knobs, right? It's just a rotary knob. So you just spin it and it just displays the time based on the screen.

Host 3     14:00

Oh, they don't even have stops, right? It's just a rotary No, no, no, it's

Host 2     14:03

Got it's got detents in it. Oh,

Host 3     14:05

I thought I thought it might just be a one of the column.

Host 2     14:09

Encoder encoder. Yeah, yeah. Yeah. It's an encoder, but it's got the tents on it.

Host 3     14:13

Right. But can you spend it in depth? Yeah. Mine is still like an analog click to like, oh, resistors in place. Yeah. Not like not like a digital readout? Yep.

Host 2     14:24

So it crazy thing about that old tectonics four, six, I think it's a 464 is when you open it up all the connections like the actually like, like when you flip a switch from like a B, or like, you're going to add the signals together, or you're going to like minus him or whatever, it actually moves a lever that goes like a foot back into the machine switch, and it pulls the switch forward and backwards. Yeah, it's very mechanical, and how like switches work whereas the TBS has like a has a membrane, switch matrix, and then a PCB board there that you just press into right So

Host 3     15:00

It's definitely a different experience. Tektronix is actually known for that their their power switches, the actual switches usually physically mounted to the back of your scope, actually. And it's got this big long plastic push rod they actually

Host 2     15:13

Just want the The 464 is a little tiny knob that you pull out the turn it on, and it's goes all the way to the back.

Host 3     15:22

Yeah, like there's a custom molded like, switch arm that goes all the way down. Oh,

Host 2     15:26

Yeah. Now the TDS doesn't have that. It's just got soft power switch. So

Host 3     15:32

You kind of kill all the power man. Oh, phantom power.

Host 2     15:35

No phantom power. How much power that thing pulls in standby.

Host 3     15:39

Probably not much power, because it's just sniffing for the power. Yeah, right. Who knows? It's old to my pole, like a watt. Just maybe an hour?

Host 2     15:48

Yeah, I guess I'm gonna get the what kilowatt out and plug it in. Yeah. Cool.

Host 3     15:53

So yeah, that's something I've been using recently. It's cool.

Host 1     15:56

I'd rather give that a shot and make a video or something. Yeah. Because I've never done that before I can.

Host 3     16:02

I can plug my my new filter into it and kind of give some make we can make some gifts out of it.

Host 2     16:12

So last week, I was talking about the Gameboy. Did you get the code to compile? Yeah, actually, I pulled out the Gameboy. It was like all mess, right? Because like, of course, it's just sitting around and sitting in a box and thrown around move like three times. And so all the cables are messed up. So I got all that the hardware and stuff and then downloaded my because I didn't have the stuff on my computer anymore. So I had to go to my GitHub repository and download and then compiled and it compiled. So it's so my cordus to install works correctly. That's like, accordance to the ID. Yeah, that's the IDE for Altera Cyclone four.

Host 3     16:55

Oh, okay. Gotcha. Yeah. Wow. And it was just like, no issues.

Host 2     16:58

Yeah, it just it just the project actually. 400 warnings or something it was always is. Especially for this project. Yeah. So the next step on this is actually build a board to make it work. And so I was. So the thing about the Gameboy is that you have to Pete, the Gameboy, dmg 01, which is the model number, which is the big brick gray brick Gameboy is it has two PCBs in it. One's got the I think it's a Z 80 processor, if I recall. But it's got all the processor stuff on it, power circuitry, all that stuff. And then it has a ribbon cable that goes up to the front board, which has the screen speaker and buttons on

Host 3     17:44

It. Isn't the speaker at the very bottom of screens up at the top? Yeah. Is it like a L shaped board or something? No, no, it's

Host 2     17:51

A it's two boards sandwiched together. Oh, and they're both full size. So both

Host 3     17:55

Sides. Okay. Okay, gotcha. And so you're gonna slide yours in between them? Well, that's

Host 2     17:59

What the idea is. It's actually quite a bit of space in there. Oh, so you can you can slide it in there. But the trick is that, I want to put it in that ribbon cable, because it's the perfect spot for it. Because all the LCD data, all the button information, all that stuff comes across it. Ah, so you just cut it and sniff it. Well, I was going to get to shorter cables, and then put my board in between Yeah, yeah. But the trick is, I remember from back when I was doing this was it's very hard to find that cable size. I actually had to get them custom made.

Host 3     18:32

Really? Ollie Express or something.

Host 2     18:35

Yeah, actually was Aliexpress it because they're 21 pin, which is kind of weird. And it's a weird pitch. And if I recall, I actually started looking through like, my, like cold emails trying to find when I was talking to this person over in China and over ally Express, like, what were the specifications? I can't find them. Oh,

Host 3     18:54

Is it like a two millimeter pitch or something? 1.250 So like, it would like the first two would line up in a regular connector, but then it would cascade

Host 2     19:04

Well no, no, no. 1.25 is kind of standard, isn't it? point two seven? No, it's 1.25 it's kind of standard. The problem is there's not a lot of connectors for it. A lot of them are like the vertical only I need a horizontal connector so that I can lower the profile down. So I think what I'm going to do is get actually get some custom Flexi cable made for this flex PCB. Yeah, I get a flexible PCB and so I can put the connector the right size on one end that will plug into the the, I guess the main board with the processor on it, and then the display board on top and then on the other ends, instead of using connectors just design the flexor cable to be dragged soldered. So it has like the little weird, like semi circle ends on it on the cable. Yeah. And it's designed to basically tape it down in the drag solder the the connector and

Host 3     20:03

And then drop some hot snot on top of it. Yeah, yeah, yeah, some glue.

Host 1     20:07

And that should be fine.

Host 3     20:09

Wasn't the original Gameboy, sort of like a, an evolution of the NAS hardware? No, I thought it was like, like a like a almost a similar thing. Nope. What's what's different?

Host 2     20:20

It's a completely different processor. So the Nintendo runs on a 6502. Right. And I think I think the Gameboy is a z 80. Okay, I could be wrong. It's been a while since I looked at it. Yeah, it's a z at z will completely different architecture, all that stuff. Okay. Okay, but so so like, everything is different about Yeah,

Host 1     20:43

Including how its programmed. Yeah.

Host 2     20:45

So that's actually the funny thing is on the SN Yes, you know, you can get a game board cartridge adapter.

Host 3     20:51

Yeah, it's a whole Gameboy in the car in the cartridge. So

Host 2     20:55

That's the thing is the SNS is an evolution of the NES. It runs a very similar processor runs very similar. A lots of it actually was originally designed to be backwards compatible. All that would have been cool. And I don't know why Nintendo decided not to. But that's actually one of the big things is because it has the snare still has an eight bit wide bus, which is kind of its downfall. But oh, so it has to hammer

Host 3     21:23

Everything at least twice to get anything done.

Host 2     21:25

Yeah, yeah. What cuz it's not a true 16 bit console. Could has an eight bit wide bus, but

Host 3     21:33

It's memory with its 16 bit right? Yeah, yeah. Yeah, I've heard a call run a while. So everything has to be done twice. Yeah.

Host 1     21:41

Or twice as fast.

Host 3     21:43

Well, I mean, toys is fast still, that just has to be done twice no matter what.

Host 2     21:47

Yeah. So. So yeah, so you get this weird connector and weird pitch with and stuff on this thing. So it makes it really hard to find something to connect up to it. So I'm just doing Flexi cables and just order a bunch from the get go and just be like, well, hopefully the right and I get skipped to use them later down the road for the actual product. So you're gonna

Host 3     22:06

You're gonna just hot air off the old connectors and just so no,

Host 2     22:09

So that connector, these these Flexi cables on one end will be designed to go into the original. Okay, on the other side, they'll be designed to be dragged soldered on your board. My board. Gotcha. Okay, so

Host 3     22:22

You're not going to modify the Gameboy side at all ideas not to Gotcha. It's just a phantom board that that goes in there. And a Gameboy is not even aware that it's there. Correct? Yeah. Okay. Okay, gotcha.

Host 2     22:32

Yeah, that's gonna be the idea. So that's the next step is to get that built.

Host 3     22:37

Is there any kind of issues that you see with the Gameboy? I guess passing information between the boards, because it's going to have to pass through your board?

Host 2     22:47

Yeah, um, I actually tried a longer cable and it was fine.

Host 3     22:52

Well, okay, so your code doesn't like it. There's no appreciable, any kind of issues with it. Like it doesn't slow things down or any data packet issues?

Host 2     22:59

Not really. Oh, because all it is doing is it's, it's got you know, high Z now. Yeah, high Z inputs on the, on the well, high impedance inputs on the FPGA. And so and they're just on the bus.

Host 3     23:15

Oh, okay. So it's not, okay, I got, it's not passing through your processor, your processors just like stealing it just snipping off of it. Okay. Okay. I thought I thought I thought you were putting yours in line with

Host 2     23:27

Every No, no, no. So it's gonna snip the LCD boss guy. Now the buttons are going to go through the FPGA and back out. Okay, now, that's only going to have like a 20 nanosecond lag, which

Host 3     23:39

You won't be able to tell. How do you know it's only 20 cents? So that's just the gate speed. Okay. You found what the propagation was? Did the I guess the IDE tell you how long Yeah,

Host 2     23:52

You can just look at it. I mean, 20 nanoseconds is. Yeah, I mean, it's pretty much it goes. It's connecting to iOS together. That way I can. I can break it if I need to. In the code. Yeah. And do extra processing or something.

Host 3     24:07

Some dude out there who who plays super smash brothers would be like, I do not accept a 20 nanosecond delay. That's the difference between winning and losing.

Host 2     24:20

But yeah, so that's, that's the first insight for me of like a finished one. I just want to put like a VGA port on it. I'm going to use I think last time I was talking about like a DAC but for the first one. It's just going to be a resistor network. Make it as close as what I originally had as possible and make it easy to work on.

Host 3     24:39

And your board steals power right over the the

Host 2     24:43

Yeah, it's got a five volt line on it. Okay, everything's five volt, so I actually have to use a little transit level shifter to knock it down to 3.3 for my FPGA.

Host 3     24:52

Gotcha. So So like all said and done, you won't need anything other than this board with its two Flexi cable Yeah, and then a hell of an HDMI port. VGA effort. Oh, I'm sorry. Yeah,

Host 2     25:04

I actually got a I can't remember who built it. I should. I should have talked about this. I'm talking about this next week is the or in a couple of weeks. I think we have a guest next week completely free German yet.

Host 3     25:15

Trade. Trade German part three.

Host 2     25:17

Yeah. Part Three. Trade German Strikes Back,

Host 3     25:21

Return to the German return.

Host 2     25:25

Return with the tray. There we go. Yeah. Yeah, so I got a FPGA board that had HDMI built into it, and actually drives the HDMI directly. Now it's, you can't do like 10 ADP, you can do like 640 by whatever. But apparently, that's a valid HDMI spec. And so I'm gonna give that a shot and see, you know, how does if I if I put the Gameboy information to it? How does that? How do TVs handle scaling up that kind of resolution? And if it looks fine, then, okay, okay, just run that. And don't even worry about actually upscaling in the FPGA to 1080 p, because kind of not really.

Host 3     26:06

I mean, on a Gameboy if you upscale, that big, I mean, every pixel is going to be like the size of your fist.

Host 2     26:14

You'll know the, my current VGA code XT 4x. It does nearest neighbor scaling. So it takes one pixel copies that three more times. Yeah. And then does that. So it's a really crisp, upscale and right. I mean, it's blocky, but that's because that's what that is. It doesn't make up data, which is Oh, it does. It doesn't do like grayscale in between. Yeah, which is a lot of upscaling does that it will try to grading it and for graphics like the Gameboy or like snaps or whatever, it that actually looks bad. Because it just muddies it.

Host 3     26:47

You know, you don't want that at all. Yeah. Whatever. Whatever upscaling. We did when we played Super Metroid. That looked we played Super Metroid once on a on a YouTube video. Yeah. And we did we did something on that. And that looked amazing. That was just

Host 2     27:03

That was nearest neighbor. Okay. Yeah. So it was a direct. Like, I think it was an 8x increase. So one pixel became eight pixels, basically. Yeah. Or it one pixel became eight by eight pixels, right? Just a big square. Yeah. Which makes you keep the look of this mess. But everything looks clean.

Host 3     27:22

Well, yet, the transition between two colors to adjacent colors is incredibly sharp. Yeah, if your TV can do that, so

Host 2     27:29

So yeah. So hopefully next week, I have like maybe a board laid out, we'll see. And then the I'm working on an Arduino article right now. It's about the like, the like, on an Arduino, what kind of different parts are on it? And if you're using that for like your, your project, like let's say you prototyping with an Arduino and you're starting to go to your product, what pieces do you actually need? And like what kind of considerations you should think about when making that switch from a two layer prototype? Basically, an Arduino with a that'll come hats. Shields shields? That's right.

Host 3     28:15

It's been a long time it had Sir the PI World. Yeah,

Host 2     28:18

I really wanted them called plates. Because a Pipelight

Host 3     28:23

A hat is an acronym, isn't it? i Yeah, let me look this up. I think I think hat actually stands for something. So

Host 2     28:30

Yeah, so it's gonna cover you know, the I'm gonna basically break apart the schematic. What each part does, because the Arduino has a really interesting power MCSE system, like how it switches between USB power and DC in from like, the DC jack, or the V in pin

Host 3     28:50

Will and so like, if you are transplanting a, the guts of Arduino to your project, it's almost guaranteed that you're not going to need everything that's on exactly Arduino. Yeah, so yeah, that's, that's it, you know, I was actually reading an article this week about the STM 32 chip. And or was an article I'm sorry, was a forum post. And I totally feel for this guy who posted on there, because he was like, Look, I'm a newbie, but what do I need to make this thing just work on my board? And the second question, which I feel is like a really neglected question by a lot of people it's like Okay, so I've got power to my microcontroller my microcontrollers hooked up every possible way that I wanted to. How do I program the damn thing? You know like yeah place and I feel like I feel like so many of these manufacturers miss a really good you know, meaty topic right? They're just like, hey, if you need to program it you need this this and this. Here's the pins. Here's the connection. Yeah,

Host 2     29:51

Actually, if a from microcontroller you had like the bare bones. What like a schematic that was the bare bones of how this microcontroller works. Okay, yes. And then, like, let's say a medium project, which is like, let's just try to get some peripherals working. And then the full monty of everything.

Host 3     30:10

You know, you that would be so helpful for a lot of people. I mean, myself included, and in a lot of cases. By the way, Iris just found out what hats are they they're called hardware attached on top. Okay, it's, it is what it is, is that you don't include the on? Yeah, every

Host 1     30:31

Haute. Exactly.

Host 3     30:33

You don't do that hot button. Okay. So take take, for instance, like, let's say, let's say you wanted a 328 p, because we'll use that because that's the hard one. If you wanted a 328 P, and you wanted USB capability. Yep. And you wanted it to run on five volts. It would be awesome. If there was just like an example project out that that was like, here's all of those things. If you do this, it is practically guaranteed to work. It may not pass like CEE and may not pass FCC and may not do any of that other jazz. But like, you just put these things in your circuit. You know, we're gonna work. Because I mean, you've you've personally built like your own, like, building block library. Yep. I have a couple of my own to like, when I'm working with a particular chip. I have a way that I like to do USB. Yeah, that like, I've done on projects before. I know it works. So I just take all of those parts and copy paste. Yeah, right. And that's kind of the beauty of that kind of stuff. However, it's like building that library of those building blocks is not particularly easy. You know? Something like that would be would be super awesome for the Arduino world.

Host 2     31:40

I think it probably does exist. But I haven't searched too hard on it. So

Host 3     31:45

Yeah, the thing is, like, if you don't have a good knowledge of it, then you get it gets confusing really fast. Yeah. Especially like I mentioned this in the last podcast, you know, when when Arduino moved away from the FTDI to the to their own custom programmed USB controller? Yeah, like, that's really confusing if you'd have no clue what that means.

Host 2     32:05

And the thing about that chip too, is it's like the same is actually that chip it's like a 80 Mega eight something a 16 you for like eight you

Host 3     32:15

To one

Host 2     32:17

Um, the funny thing about that chip is it has more pins then 80 Mega 328 P

Host 3     32:25

All these it's purely there to sniff USB Yeah, do USB serial.

Host 2     32:29

And it's not cheap either. It's actually like $2 and some odd cents in signal the signals singles Yeah, and you got a crystal and bunch of other stuff you need for two

Host 3     32:41

I guarantee you the Arduino guys got some kind of deal on it or they were they worked it out with the right ones

Host 2     32:48

Back then the only other opposite they were using the Dewey MOBA whatever it was called as a preferred no one can pronounce that one. Yeah, it was before that Uno. It the only option was a ft 232 RL, which was like a $4 chip. So this was probably good. You know, it probably caught cut two bucks off the bomb. Right now. You've got like the CP 2000 Something which is like a Silicon Labs chip, you got the MCP, blah, blah, blah from from Microchip and then you got a you got ft 230 x from FTDI now, and then you've also got, there's a lot of players in the game. Yeah, ch 203, which is that Chinese one that no one can buy unless you go on AliExpress.

Host 3     33:33

And then you have all the counterfeit ones that just don't work. Oh, man, I actually I have a project that's not a project. It's something that I built that a guy put together that it's a really fantastic project called the mute tester, like the Greek symbol Mew. And it's it's a tube tester on that. I wish that would that would be fantastic. I think the guys from Denmark, where they probably don't use uhm, locks, but but they're not far away from the people that do. Regardless, he designed this entire thing and the whole control system is on a one of the big like, pick chips you know, like the real long dip chips that have like 40 pins, but they're enormous. Yeah, and I love it because you can still buy that chip. It's just like Wow, dude like, you know,

Host 2     34:19

There's a lot of other chips are like a, I guess he's comfortable with at Mega 644 P. Like the monster has a monster. And I actually was using that one man like eight years ago, because it has dual you arts. And we wanted something that was Arduino compatible back then.

Host 3     34:36

Oh, yeah, it works. Yeah. So so the thing is like, he's got this pic. And I guess you already out all the code written for it and it works really stable. So in the kit, he provides this whole thing that you build, and then you have to wire off to a dB nine connector. And then you have to go DB nine to USB. So it has to have that little like wart in the middle there. The serial converter yeah and stuff. And it's just like man, the whole like wiring of DB nine connector and then you have to go buy an FTDI USB two DB nine connector changer thing like could have just put a USB port on this Yeah, like been done with it. So it's it's, I mean it's super nice now that like USB, talking all the way down to your metal hardware like super easy nowadays, but at the same time, it's not. I mean, I don't think there's like, personally, I don't think there's a lot of good information on that, or a lot of good, like, really distilled information. There's tons of capability out there and there's, there's tons of ways to figure it out. But, you know, a building block. Personally, I don't know if I've seen that a lot. I mean, SparkFun has some stuff I've seen, I've seen them write some stuff, but like, it's still not as like straightforward if he asked me as it could be. Yeah. I mean, hence, DB nine connectors. Yeah.

Host 1     35:58

The fact that someone's still using that. I

Host 3     36:00

Mean, the reliable the robust. Yeah, and it's not gonna break or anything like that, but at the same time, it's like, okay, great. My USB cable breaks. I just get a new one for $1 Yeah.

Host 2     36:12

Cool. Yeah. So onto the RFO your first little bit weird, but whatever.

Host 3     36:18

Which one isn't yesterday we talked about the fat burger. Yeah, remember like that officially said the fact that the RFO is weird. Yeah,

Host 2     36:28

It's all speaking that there's inclusion to it. So a couple I wish we brought this up when it actually happened. I just forgot to put it on the RFO they cleared it out when launching it no Unfortunately not. But they're actually taking a piece of it and put it in a museum what yeah

Host 3     36:49

My gosh, that's amazing. Yeah, like why just like it's its history. Its history. Yeah.

Host 2     36:55

The largest fat burger in the world would be in like the most it'd be like right next to like King Tut's mask I think they have that in the British Museum of whatever it is. A probably I match all his

Host 3     37:10

Notes. I feel I feel like it is worth mentioning because we do have listeners that have not listened back in like six years on the fat Berg was a giant sewer clog in London. Yeah. Of of fatty material. Yeah. And why that shows up on electronics podcast. I don't remember exactly why it was funny as hell that I remember at the time. We laughed pretty hard at that. So figure out how to get it out. Yes. Yeah. That's how we did right. We were Joe and we, if I remember, right, we had talked to heavy robotics. And they had talked about they had like Sewer Cleaning robot. Yeah, that's where that bird came from. Yeah,

Host 2     37:52

They said that once you put something in the sewer, though, you can never clean it. It always has. It's got like perma crap on it. Yeah, well, no matter how much you clean it and bleach it, whatever. It still has that feeling to it. That is Yeah.

Host 3     38:07

Episode 85. That's a while ago. Yeah, it's got some ninja turtle slime on it.

Host 2     38:14

So yeah, I'm RFO so the I got an email this morning from Digi key bought new product. So this is not a you know digit. He's not paying us. I wish

Host 3     38:25

Though. I mean, if you want to Digi keys, that'd be Yeah, it'd be pretty cool to be called

Host 2     38:29

The macro fat Digi key engineering podcast.

Host 3     38:31

Hey. Send us money. And I'll buy parts from

Host 2     38:41

So this is a this just struck me because how crazy this part is just from a we like crazy parts. I'm like I just didn't know these kind of parts existed. It's called the QH l 600. By x p power. And it's a dc dc brick converter, but not like a brick converter, like you would say for your laptop. It's like a metal brick

Host 3     39:07

That goes on your board. You solder it directly to the board. Yeah, yeah. And it's

Host 2     39:11

4.6 inches by 2.4 inches by half an inch is how big this thing is. It's got like mounting bosses and things crazy looking.

Host 3     39:19

Oh, it's actually made of aluminum or steel metal. Yeah,

Host 2     39:22

Aluminum laundry on top. You know what I forgot? I forgot the price of this thing. I didn't. I didn't look it up anyways. They're designed for around 300 volt DC inputs. Hmm. And they regulate down like 512 24 like normal voltages. But yeah, be 180 volt to 425 volt inputs. And the thing about it is it's the description like what is this thing used for? I'm like, okay, like if you rectify 240 volt you get 380 DC Yeah, so they would work for that. And they're like, oh, yeah, for, you know, high voltage batteries for like electric cars. Okay, that's cool. But then says he s g solutions baseplate ideal for cooled ESG solutions. It's like what is what does

Host 3     40:18

He say? Electrostatic? G?

Host 2     40:22

Yeah, I don't think it's electrostatic either. So if someone out there knows what baseplate cooled ESG solutions is I've Googled, looked it up. Cannot find out what this is, huh? If no one lets us know, by next week, I'm just gonna email like, XP power and be like, let me know what the hell what is that term? What is your technical writer think that term means?

Host 3     40:48

Hmm. I'm getting a bunch of stuff. There's environmental, social and governance. Yes. There's a band called ESG. As a rapper called ESG. Yeah, there's, I don't know. I'm interested now. So I actually

Host 2     41:08

Race plate cooled and large snake gates. What? And large snake gates snake.

Host 3     41:17

Just like opens up it takes like, it takes 400 volts to open a snake gate.

Host 1     41:25

But it's only for like four constructors.

Host 3     41:27

Oh, yeah, right dude will be enlarged. Just the regular snakes are like 100 volts, you know, 100 volts or something like that. Right before I started at macro fab, I actually designed a product, I was doing some contract work. And I designed a product that was actually had very similar specs to this where the voltage actually was a little bit different, I had to design one where it could accept anywhere from 60 volts to 390 volts or something like that input. And it had to drop that to 24 volts. And then it had to drop that again to five volts. And it I used it in a, it was a valve controller for industrial stuff. And I actually found a, I don't remember who what it was, who it was, who paid it. The it was a while ago, but I found a chip that could do it. And it was it was an absolute pain in the butt to work with it had like all these weird virtual grounds and all kinds of stuff to make it work. But eventually, it actually ended up working, you could put AC or DC into the thing, practically anything and it would it would drop it to 24 it was not very efficient. You know, like, Yeah, I think on average, I was getting 50% efficiency, but all said and done. For this application, it was it was still low power anyway. So like one watt became two watts, whoop dee doo. Yeah, that kind of thing. Like in an industrial situation where you it was a safety situation for valve control. So like, it didn't matter to watts wouldn't wouldn't matter. So, but this kind of stuff is actually pretty difficult. The thing that's different is, this is what 600 To 750 watts.

Host 2     43:07

Yeah, they have two different models. One 601 750

Host 3     43:11

That's hardcore. Yeah, to be able to handle that much current at at that kind of juice. That's, that's hardcore. Yeah. Wow.

Host 2     43:19

It's pretty cool. I just like how it's like this ginormous brick of aluminum. And that's a part. Yeah, yeah. I've never seen a part. I think it's the largest part I've ever seen, besides like, ginormous connectors, but those don't really count.

Host 3     43:33

You know, what's nice about these power supplies is a lot of times they're pre compliant. And so you can just buy a switch mode power supply, and know that its own radiation, or conductance is not gonna be a problem. Yeah, it's not gonna be a problem with your product. So, you know, spending a little bit more on that it's not gonna make it a lot of times really great. However, these bricks can be kind of expensive. Yeah, I know, I look up how much I guess I guarantee it's not cheap. But but if you if you think about it, this thing, if you're, if you're rectifying 240 volts, and you're dropping it to your five volts or whatever you need. You don't have to pay for the cost of a transformer. Now. So if this is going like, okay, so take for instance, if you have a control panel, and inside that control panel, it's controlling some big 240 volt motor or something, or even higher than that, really, if it's controlling something big, and you just need a small little five volt computer in there. I mean, this thing alone will take care of that.

Host 2     44:33

Yeah, and Well, it'd be way overkill though. Cuz that's like, you know, 600 it's a it's 100% efficient, which is not but 600 watts at five volts. Well, you're talking like 120 amps.

Host 3     44:46

Sure, sure Show. So assume that this thing is also controlling a host of like relay controllers or something like that. Or if it's a big hefty PLC that runs on five volts. I mean, I don't know of any PLCs that run directly on five Most of them are 24 but still like this and all of Amazon's version. Okay, sure. So, so I mean, the thing is like, this is sort of like, a seems like a one stop shop for. Yeah. Power power big control box. Yeah. So that's kind of cool.

Host 2     45:15

Yeah. Alright, so the next one is a Reddit post. It was on the slash are slash electronics. And it was someone bought a really cheap power supply on AliExpress. And was basically just got it in was just looking it over and notice that one of the caps looked funky. And it was a ri, like they put a new covering on the cap and a cover. And on the outside, it was like a 240 volt power supply input. And so you would need like 380 volt caps on the inflow, you probably need like 400 volts, right? 450 volts caps on acid rectifier? Well, it said 450 on it. But when you cut the outside of it off, it actually was a 300 volt cap. So they just put a new it's not a shrink, it's shrink wrap. But it you know, the shrink wrap that's got the labeling on it. That's what they put over the caps. Yep. So they basically remarked the cap at 300 volt cap as a 450 volt cap.

Host 3     46:24

You know, okay, so there was a company that I dealt with back in like 2008 2009. And they sold kits for building guitar amps. And they got in a bunch of trouble, because their their guitar amps were failing. And caps were exploding. And I was I was on there for a long time. Yeah, exactly. And, and in fact, here's a picture right here. Here's a picture from kind of back in the day that may have moved on. Yeah. So so there was a Chinese company that this that this company I dealt with, was buying caps from that that Chinese company was literally no risk in and re skinning caps at a higher voltage range. And even in some cases, a different capacitance.

Host 2     47:10

Yeah, so this one was saying capacitance is different voltage. Yeah. So I want to talk about is how do you test so let's say you bought, the best solution is you just buy caps from authorized dealers, right? That's like the easiest route well,

Host 3     47:25

And the manufacturer's name is written on the side. And it's a good manufacturer. They actually

Host 2     47:29

Like partly spoof that to the probably use these like Nicki cons that they're probably not negate cons. But how would you test without without destructively testing? The voltage rating on a cap?

Host 3     47:44

I was about to say it's pretty easy to destructively test. Yes, keep ramping up the voltage blew up there. That's it. Yeah,

Host 1     47:52

That's the top in?

Host 3     47:53

Um, I do you have a solution to because I think I have one.

Host 2     47:56

Yeah. So I actually saw because I didn't know either, I saw I started searching, like, how would you test it. And so I started looking at like cat Database, Data Sheets. And because the capacitance changes, especially for lecture lyrics, they change as the voltage changes. So like, on the lower end, you get all your 1000, microfarads, or whatever it's rated for, but as your voltage ramps up, it goes, that goes down, and D rates at a certain rate, and like the datasheet, for the cap is going to say what that is, and blah, blah, blah. But say that you just bought caps that were spray painted black, or they only have covers, so they're super sketchy. So the trick would be to measure their capacitance. And I think what you do is you measure the capacitance over a spectrum of voltage, until you start seeing a drop off in capacitance. And then that's probably right around where its rating should be. Because then basically, once you start getting closer and closer and closer, it'll start dropping really fast off and stopping the capacitor.

Host 3     49:00

And then short, I think what's actually Okay, so the what, I'm probably gonna talk a little bit out of my butt here, but one of the factors that that determines the voltage rating is the, the dielectric Well, no, I mean, the dielectric is pretty much the main factor. Yeah. Because, you know, if you go above what the dielectric is, you break it down and you arc across it. So that's, that's your main factor in there. But the the ESR the effective series, or Yeah, the effective series resistance, and your leakage current through that will change also, cuz you go up. So if you if you both put an ammeter on there and your voltage, as you go up, you see how much more current it starts to draw. And when it starts to draw an appreciable amount of current, like if it's, you know, if

Host 2     49:49

You're, if you've got to graph it out, and once the graphs changing, when the graph starts

Host 3     49:53

To curve, you see a knee in the curve, basically, you know, you're gonna see something real thin and then it'll start to turn An up and hockey stick hockey stick Yeah, it'll hockey stick, kind of right before the hockey stick happens there that's easier.

Host 2     50:06

That's easier to test and capacitance II way easier

Host 3     50:09

But you're looking at small Well, depending on the capacitance of the capacitor itself. You're looking at small currents.

Host 2     50:15

Yeah, well for electrolytic you should be able to read that

Host 3     50:19

Big Electrolux are going to have a lot of leakage current so it shouldn't it should be in like the micro amps. Yeah, but if you're looking at like, if you're trying to figure out like, like a ceramic, small ceramic capacitor, you're looking at like pico amps. And that gets a lot harder to read. But you know, this issue isn't going to happen in this small ceramic stuff in the big Electrolux the leakage current will probably tell you most Yeah,

Host 2     50:43

We should try this out. This should be this would be a lot fun test. See if that if that works.

Host 3     50:48

Let's just try flipping them backwards first to see what happens. Have you ever blown up a cabinet backwards?

Host 2     50:55

Nobody has have done it by putting a ton of voltage on it. I think I tweeted about it. I had it. I was testing my slow motion 200 FPS on my picture.

Host 3     51:03

Remember that? Yeah. Yeah. get cancelled blow up forwards or backwards if you abuse them. Oh, yeah. So there's a lot of there's a ton of energy in there. You don't realize that they have that much energy and it's a little tiny. Yeah, yeah, evil dancing Pixies.

Host 2     51:20

So listeners if you ever purchased counterfeit or fake parts, let us know. And I think we'll just wrap up the episode from there. Yeah. So that was the macro engineering podcast. We're your host Parker Dolman and Steven Craig let us know if you bought or accidentally I guess bought fake parts. If you unwillingly known you bought fake parts and what happened

Host 3     51:45

Are you still alive

Host 2     51:48

They're tweeting us zombie Twitter's take it easy

Host 2     52:02

Thank you yes, you our listener for downloading our show. If you have a cool idea project or topic or counterfeit part you want Steven and I to discuss Tweet us at Mac fab or email us at podcast at macro calm. 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 wherever you listen as it helps the show stay visible and helps new listeners find us. I think we just hit five reviews on pot on iTunes.

Transcribed by https://otter.ai