Josh Rozier starts his design of a power transformer, the DOOM SAO gets more code, and the MacroAmp is 90% done!
Parker gets test results from his APA-102C experiments and Stephen wraps up REV2 of the MacroAmp!
Parker explains the DOOM SAO and Stephen implements a Gyrator for the MacroAmp!
Visit our Public Slack Channel and join the conversation in between episodes!
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 are your host, Stephen Craig and Parker Dolman. This is episode 172.
Okay, so last time we were have we had a podcast, I was working on the penetrator pinball platform. Yeah. And I got my breakout boards for the ATC MD 21 g 18. A back from the FAB, and it'll works really cool. So I set one up to Ben for testing. And he actually got his today and was able to get some test code running on it, making sure the comm like the USB type C interface works, that all works fine. It the debug port works. So that's really cool. So like basically next steps for that is to start doing the power design and testing for the penetrator. So I'm going to make those individual boards as well to test those. And so you know, building a, you know, 10 inch by six inch board all the way out, just built like little tiny modules. So we know everything functions before we integrate it all. Cool. So that's, that's next step. And I'm probably going to use like ti workbench to do the power supply design. I'm still trying to figure out if I want to use because I needed some kind of input protection. And I'm like, okay, TV s and ESD protection is a given. But I like to do like overcurrent protection for this kind of stuff as well. And so I can do fuses, which are actually pretty inexpensive. Fuses are pretty inexpensive to integrate onto a board. I think we were using like 20 millimeter fuses on the pin heck. And on the
yeah, those are the ones where you had the LED underneath them, right. Yeah. So
the LED would light up at the fuse blue. No, the LED would go out at the fuse below blue. That's how it worked. Got it? Yeah. I think there's a way to make it so that go it lights up the fuse blows by can't remember how that works. There's a way to make that work, though.
Yeah, you could just have the output control that transistor there that would flip it.
Well. I've got some automotive fuses like ATC style automotive fuses that only have when you look into them. They just have an LED. And they light up when the fuse blows. So I don't know how that is working. Exactly.
Huh. Okay. Yeah, that's strange. I mean, it's two terminals, and it when it blows it.
I had to look up how that works.
When it blows it shorts the leg of the LED somehow, I guess so. I don't know. That's weird. That doesn't make any sense.
I bet you what happens is it blows. Yeah. Which allows current to only go through because if it otherwise the LED, gets shunted. Right, right. And I think if the, if it blows, it probably limits the current, how much is going through it because there is a path to ground somewhere on the other side. Oh, so
the fuse is in parallel with the LED is what you're saying? And then the parallel section breaks. So everything has to flow through the LED,
led, and I guess that probably limits the current so you don't blow the LED and you're melt your wire.
Okay. So it's not preventing everything from flowing. It's just preventing it down to whatever the LED is.
I would I want to guess that's how that works. Okay. Yeah. Okay, that would make sense. Yeah. Okay.
I mean, the whole point of abuse is to break it entirely. Entirely. Yeah.
So I don't know if I want to go with those 20 millimeter glass fuses, again, I'm thinking about going with, because the whole idea is to make the pendant or smaller, and those are pretty large components on the board. I mean, they're like an inch long by, you know, a third of an inch wide, something like that. Point three, three repeating inches one, of course. And, but they're inexpensive. And so we were using an older version of the pen hex system, we were using like an E fuse. Yeah, like, monitor the current and then it would Oh, like it would close the fat or open the FET if the current got too high, right, right. Which is nice, because then you just reset the power and it would, you know, it would make it a it would close the MOSFET back up. The problem was Those are expensive. Those are like four bucks. I see. Yeah. And so and then another thing is what the pennant but the thing is, they're tiny because they're like the size of like a I think they're like a DSN eight package like, you know, five millimeters by five millimeters in size. But so they're expensive. And the thing with the printer is to make it cheaper than the pin hex system was. And so I started looking at like, maybe we can use like automotive ATC mini fuses, because those are, you know, they're like 10 millimeters or so wide. So they're tiny. And they can give them an all the current ratings that we would need. And so I've been looking at like the mounting for those, like, you need the socket from plug into. Yeah. And it wouldn't be nice as I can find a surface mount one of those just to reduce the labor cost. But I can see like people fumbling and dark and then like ripping a fuse off. So we got to go through hold on that regardless. So that's that. And then I got the wagon years that that tack installed. Oh, yeah, yeah. Yeah. So I already had the power and ground already there underneath the dash for the other gauges. And then I just ran the wire from the tack into the cab and put some sheet metal screws into the plastic Dash. And that was it. Cool. So I haven't done the documentation yet on my blog, but I will get to that sometime this week. So that people can look at it.
You know, this just came to mind going back to the fuse thing. I absolutely detest it. When you open a product up and you see a through hole fuse. You ever seen those the 20 millimeter bodies that have a lead? Coming? soldered them in? Yeah. And they solder that it's like, oh, geez, thanks. You know?
Well, I mean, at least it didn't burn your house down when it blew.
Yeah, but it's also a little bit of a middle finger towards repairing it, you know?
Yes. Because you have to dishonor something. Yeah, you have to
de solder something. Most of the time. That means whatever board that it's connected to, you have to pull that entirely out of it's just a pain in the butt. Oh, yeah. Oh, yeah. I hate that. It's like, I don't you know, can you just buy those right off of Mouser? Or DigiKey? Or do the like, I haven't even seen those. I mean, I haven't been looking for him. But
I don't know if you can buy those at like Mouser DigiKey. Because they are normally in like, really cheap appliances and stuff like that.
Right? Right. Something where they wanted to automate everything and everything.
And well, they don't have to have the connector in there or the holder. Right cuts out a bomb item. It cuts
out a bomb item. But it also cuts out the labor of after that's been done. You have answered the views.
That someone just putting the fuse in there. Yeah.
I get it. You're saving a few pennies. But
yeah, you're right. Not a
lot of yeah, you're not saving headache, that's for sure. No, not
done? Well, you got to think of like how many of these units the fuse actually does blow before the user throws it away? Oh, I'm sorry, recycles it.
Whatever. Luckily, I don't see those very often. And you're right. It's just kind of unlike the lowest of low grade stuff. You see that in? Yeah. Cool, though.
You see that a lot in thermal fuses. In Nevada, Oh,
yeah. Thermal fuses, where they they wire directly to them and then put heat shrink around it? Yeah, they
have that like, Kevlar, Kevlar. Kevlar. They have like, kind of like heat resistive sleeve over it. Right. Yeah. And then they like, tape it to whatever they're monitoring. You that's really really, really annoying because it's like, okay, it's because you never really check for them. Yeah, it's always like hidden somewhere. And, yeah.
Oh, yeah. You know, not last weekend, but the weekend before I was actually smoking some bacon. And I made a, I made a smoker out of a trashcan and had put a I bought like a really cheapo electric griddle basically, and just put it in the trash can and use that to generate smoke, which totally works great. I mean, what kind of trash can plastic trashcan? No, no, it's one of those old galvanized ones of steel ones. And I put the I did I did a bit of research on it and seems to be safe.
The galvanizing the zinc is fine. I doesn't get hot enough to
do anything negative. So I also I wanted to try smoking without buying a smoker y'all can't see but like, but Stephens like eyes twitching. So here's, here's the here's the whole point of the story. If you put one of these cheapo grills or hot plates in the bottom of an enclosed area, and then you crank it to max it it's inside The chamber it heats up. So then it's thermal fuse reaches that limit. And so like it's self regulates itself at a low temperature. So it actually works. However, that low temperature is really low. So it's kind of annoying. I was thinking about going in there and sure enough
a Yeah. So I guess you put like the one or whatever you're smoking on top of that hot plate. Yeah,
you just put a little cake pan, put put the wet wood in there. And then I bought a grill great. And just set the grill great inside on the wall. I put some bolts in the in the trashcan and then put the grog into that and I smoked six and a half pounds of bacon, and it's delicious.
That might be one of the most redneck things you've ever done on the podcast.
Oh, absolutely. Yeah. Yeah. Might be might be better than then. The 5000 Watt USPS box. I think that beats it. Yeah, for sure. Yeah, but the bacon is delicious. It's really good. So maybe I'll buy an official smoker now that I've tried it. And because it because it was like it was like $15 to just give this a shot, you know? Yeah. Did trash can was clean. I'm making sure everyone knows that. It was a new trash can. Like everything is good. I did the I did my research on it. Yeah,
that's when for tailgates for football. And I always bring a keg. I always do like the trash can with the keg. I always buy a brand new trashcan. Because like there's no way no matter how much scrubbing, you're never going to get that trash film. And so it's always gonna be like, it's always gonna have that stink of trash,
Wolf. Yeah. Right.
So besides smoking bacon, what have you been?
Yeah, yeah, I've been doing some mushrooms. Okay, so I actually bought this pretty cool little product. But had, I have some kind of like, I don't know, I want to get your opinion on this, some qualms with it. So there's a there's a technique in recording, that's called the Fredman technique. And basically, what it is, is, there's sort of like a legendary mic that called the Shure SM 57, which is like the go to for almost everything guitar, you know, unless you're trying to do like a really nice acoustic sound or whatever. If you're doing just generic electric guitar sound, it's almost always done on an SM 57. And the SM 57 is a little pencil, not little, but it's a pencil style mic. So there's a cool technique you can do where you take two of these microphones and you put them at 45 degrees to each other that two heads of the mic. And using that phasing, you can actually remove a bunch of hiss and fizz from your recording, basically, you record both of them. One, I mean, you can you can set the angle of how both of them are in relation to the speaker. But in general, one of them is usually facing directly on. So one is at this third dimension 45 away from the speaker. And depending on how you blend the levels of them, you can get a darker or a brighter sound. But combining the two, the two phasing between them actually gets rid of a bunch of nasty hits and fizz. So I actually originally saw this product or this technique on a YouTube video from the channels called Spectre Sound Studios. There's a whole like, ya know, three minute video of them doing this and him one of the main guide discussing like how you blend appropriately, but then he also shows like the phase difference between the two mics and you let you listen to what is being extracted from the sound. And it sounds awful. So that's, I mean, it's great. That's what that's exactly what you want. So he brought up this product that's called the Wilkinson audio Fredman clip, which is a plastic clip to which you can take two of these mics and it holds them both at the appropriate 45 degree angle. One mounts on one mount and that's the big thing like you, because you can easily do this with two mounts, but as soon as you want to move the mics or anything, you have to do both of them, you have to get it perfect. So with this clip, you can hold two mics, they're always at the right angle, so you can experiment with how you like the placement. Or you know, a lot of times guitar cabinets have more than one speaker you might want to try one and then the other bubble but so this little clip holds the two mics together. Pretty neat. Now in this YouTube video where he's describing this clip, he talks about the Wilkinson audio guys and that they're gonna he had a prototype of it and he was like he said, Hey, you know these these things are going to get professionally Made them be available in a while. So I went to the Wilkinson audio site, and lo and behold, they had the clip. So it's Canadian website, they had it for 15 bucks with $5 shipping. So I was like, great. So I just click Buy, and it showed up. And there was something unique about it that I didn't really expect. And that's probably on me because I didn't actually look at the pictures of it. Before I bought it. I was just like, yeah, that's what I want. I know, because I saw it in the YouTube video, when it shows up. And it's a 3d printed clip. And,
you know, we've discussed multiple times 3d printing, and I'm not opposed to it. And I think it's fun. And I've used it a lot. But I just spent 20 bucks on this. And I was like, ah, you know, that's sort of disappointing.
You could have asked me to like, print something. And I was like, Yeah, sure. And yeah, no, I want to ship it to you for like five bucks next day.
Well, and the thing is, like, in the YouTube video that I saw, granted, he's not affiliated with Wilkinson audio, this, this was just purely some guy using a prototype of theirs. He said that they were going for professional injection molding, they were getting like a full on thing. And I ended up with a 3d printed clip. Now it's fully functional. Like there's, you know, not necessarily not necessarily anything wrong with it. No, but it's also just like, I was a little bit disappointed when I got it because it doesn't look like a professional product. It's like a 3d printed products. And it's $20. Right, right. Yeah. And so like, yeah, they're making bank on that, you know, they're making really good margins. And the thing is, they used a really, really thick abs, I mean, I don't know what this step height is. But it's like, four times as big as the one that you use on your
three really fast, it's printed
really fast, it feels generally robust, but the diameter of the circles that holds the mics. In fact, I'm putting it up to the video, I mean, Parker is the only one that can see it. But I have to like really force it in there. And you have to open up a 3d printed like, semi circle, like multiple millimeters. And I know 3d printed crap. They don't like to be flexed. You know, like, this is not a flexible material. So all said and done, it's kind of like, I don't know, like, how do you feel? If you ordered something and it came 3d printed?
It would have to have the 3d printed price. So if I've actually ordered stuff that's been 3d printed, but it's always been like, yeah, I it's a low volume thing. The price is correct for a 3d printed things. So yeah. Yeah, I'll buy it. But my favorite thing is I'm looking at the website and it says color choose an option. You can have any color you want. But it has to be black.
Right? And the thing is, if you look at the pictures, it's very obviously 3d printed. I mean, it's it's,
they're not the Wilkinson audio isn't trying to scam you into into that.
Well, however, however, if you look at Oh, so if you go to the Fredman sm 57 clip the webpage, the very first image that shows up for like, they're all their images, is this clip, a white version holding two mics? And it doesn't look 3d printed? It looks like if you look at it hard. But you could you could turn it on
an overexposed image. Exactly. on a white background.
Exactly. But I mean, if you click on any of the other images, so you know, immediately when I see it, I didn't go to the other images, because I knew what it was from the YouTube video. Yeah. And you're like, I want that. Yeah, I was going there with a purpose. No, it doesn't say anywhere on their description, or their additional information. Hey, this is a 3d printed product. And it looks like they sell tons of other options for different mics to do all kinds of 120s and 45 degree patterns and things. Super cool. I love it. It's great. I just kind of wish I knew it was 3d printed beforehand. And on top of that, they tried to print their logo into the side of it. Well, it's basically indented into the side because you could do things like that with 3d printing, but it looks terrible if he asked me. I don't know. I don't know. You know,
so I did a quick Google search. Yeah, and I got an STL for a Fredman sm 57 clip and I will print you this and send it to you and see which one's better.
Oh, will you? Yeah, I'd love to I'd love to do an AB comparison. Really? Okay. That actually makes me a little upset. Now I understand they probably don't have a there. How many People are buying these, you know, it clips not much. I guarantee you it's not high volume. So to get a mold made and all that stuff, you know, on the low end for something like this, you're probably looking at 5000 4000 5000 to get a mold made and then you'd have minimum orders for things like this. That you know, that's a lot of upfront capital for something like this that they probably only sell a handful a month. I well guessing,
but I'm scrolling down the Googles a bit. And so someone's actually got a Shapeways link that you can buy theirs from Shapeways directly. Now 160 bucks. 60 Yeah. $60.
Wow. And it's the Wilkinson one. No, no, it's
not the Wilkinson one. It's a another brand. Or someone designed it, etc. But it is the Fredman clip. Yeah, it's that style. 45 degree, it's designed to hold sm 50 sevens. Got it? Yeah, yeah.
So, you know, I used it. And it's fun. And it's cool. And it does exactly what it's supposed to do. So, you know, not necessarily an issue there. I'm just Yeah, I would love to hear that. If anyone wants to jump on the Slack channel. I would love to hear your opinions on. If you didn't know you were getting a 3d printed product. And then you did.
I would say if I, if I did not know I was receiving one I would be unhappy. Yeah. But I've haven't had that happen. I've always been like, Oh, it's 3d printed.
You got to prepare yourself for 3d printing?
Well, because it's that's the thing is no matter how good 3d printing is even like the really good like what he called the the powder machines, or the resin machines, you still do get the lines, the resolution lines, right. And no matter how good it still looks 3d printed and in my mind, in my mind, because I have a 3d printer and I have made stuff with it that I use a lot. Yeah. I view it and knowing how injection molding stuff works. I view it as not really inferior, but it's a cheaper thing. Oh, for
sure. Yeah, absolutely. Well, and okay, here's another thing on top of that, after I ordered this thing, I got an email saying that this could take up to a month to produce and get to me. And then I was like, Okay, I mean, that's fine. Like, maybe they have to go do something. And then it was 3d printed. And I'm like, really? You couldn't have like, I don't know, 50 of these on the shelf? I don't know. Sorry. If you're listening Wilkinson audio. I like your clip is just kind of weird.
Oh, I think it's a little I would, I would say if I was them, I would say it's 3d printed in the description.
Right and and say it's 3d printed, uh, maybe some things about saying like, we've tested this a bazillion times, it's not going to just break, you know,
I mean, I have stuff that's like in my engine compartment on my jeep. That is 3d printed. And it's been in there for two years. And so looks, you know, brand new, 3d printed stuff doesn't mean bad. It's just, it doesn't. It will never look as nice as an injection molded piece of plastic. Yeah, it doesn't scream quality. Yes. Great.
Oh, well. That's that is what it is. Right. Right, exactly. Okay. So on to the next thing. I spent a little bit more time with the macro amp and actually got one of the whole channels going entirely so my whole new tube board the whole power supply the choke going with an EO 34 driving a eight ohm speaker and lo and behold, it works great. And actually sounds pretty damn good too. It's pretty low noise, actually very low noise and the gain of 100 that I had before. works okay, actually in the Triaud mode, because the trial mode, I actually need to push it a little bit harder. So try out being the screen of the eel 34 is connected directly to the plate. So the screen grid inside is basically acting like another anode. Which makes it actually really weak and
output a whole lot less power. But even with that 100 times gain, I was able to drive it to full output. In fact, I was able to distort the living hell out of it which is cool So I can back it down a little bit. In other words, I've found like where the top limit is, and I thought I was going to do that really, really easily with 100 times gain, but it wasn't that easy, which is good. So I have a pretty nice little rage. But yeah, so the I haven't got the second channel working because I need to change a few small things just redo some solder joints and stuff. But
I was working on some other speakers to go with it. Have you seen those DML speakers, which is the audio exciter that's basically just glued to a sheet of material.
And it looks like a hockey puck and it just vibrates. Right? That's right. Yeah.
So I actually made a pair of speakers, using some cheapo cheapo DML audio, exciters that I well I didn't even glue them. They come with like this really sticky three M tape that you just stick it right on the back of whatever, I got a two by four sheet of eighth inch, three eighths, I can't remember a quarter inch, maybe plywood, just tuck them to the backup plywood. And I have my MakerLab driving a piece of plywood that just Wiggles. And um, it doesn't sound great. But it doesn't work. But it does. It does absolutely work. Yeah, plywood, or specifically, the plywood that I purchased is not the best option. I was just, I wanted something cheap that I could just test it with because I was like, I don't know, do these DML speakers actually work? And lo and behold, they actually do like it's pretty legit. In fact, I was watching some videos on it. And apparently some of the best acoustic material is Office ceiling tiles was two by four. Yeah, ceiling tiles, yeah, where you just purchase a pack of those stick these audio exciters on the back. And for some reason that pressed material ends up it has the right amount of flex and the right density to have a pretty damn flat frequency response. They're not going to
have you can make a bunch of stereo monitors, basically.
Yeah, yeah, effectively. And so I'm gonna pick up a pair of those sometime. And then because what I really want to do is just make a really, really wonky, stupid audio setup in my basement, where I want to have a turntable that goes into a custom built tube amp that plays through acoustic ceiling tiles that are hanging from the ceiling.
Yeah, I'm saying you can hang up. So it looks like like they're seeing like normal ceiling tiles. Oh, abstract. Yeah, yeah. Yeah. And then when they're off, they would actually, since you have maths up there, they would help dampen sound? Yeah, I guess you could have them as kind of like, an audio dampening. Like if you're playing music and you're recording something. Yeah, it would help dampen the sound?
I suppose I'd need a lot more than just two of them to tap
through the whole ceiling, your whole ceiling,
the entire ceiling? Yeah, that's a good idea. The so loud? Well, so I'm gonna I'm gonna drill some holes in them and just hanging by fish wire from the ceiling, and just get really stupid with it. I don't know, I think it'd be cool. And it's done. But ya know, the amp is the amp is working, which is, which is great. And Mark and I were discussing it actually a couple days ago, and sort of playing around with the idea of making a new PCB for it. Because it could be it could be better. Not actually, you know, what's funny, in terms of performance, I don't think making a new PCB, it would perform any better. I think in terms of construction, it would be better. Because if I were to do this, again, I wouldn't use solder pads for all this, all the edge connections, because I mean, everything just soldered to the PCB. And that's fine and all and it's fun for like Hobby, one off kind of stuff. But I think if I did this, again, I would put terminal blocks across the entire thing where like the transformers, just their wires, just go into terminal box blocks and get screwed down and things like that. That's a little bit more. I don't know, hobby friendly in the sense that it's like it makes more sense as to how you build the thing as opposed to all my random labels for these pads. Just like I'm the only one who knows what that pad does.
Let's, let's do it.
Yeah, I think I think it'd be fun. And we talked about maybe going to four layers. I don't know, I'll play around with it. Yeah, I
think we should go for layers and nine. The top and bottom are grounds. This is all shielded.
Yeah, just completely encased. And then
and then all the grounds are via stitched. You could see the internal traces by just the following the stitching,
you know, I did that on the box in a box. Yeah, you do that tracing? Yeah. You know, I wonder how many vias per square edge until a PCB houses like I'm not doing this, you know? Yeah, like if you put if you put the minimum acceptable annular ring on a via, and then you spaced that distance away from each other and just pockmark the entire wood would have a PCB house just be like we're not doing 500,000 holes on a three inch by three inch PCB.
It's like at when, when you're, you're building your board and you do the neg finish. And if you have over a certain percentage of your board, is that finished? They'll charge you more for gold.
Right, great. Yeah. So there is one other thing that actually both Parker and I have been working on. We have a prize that we are working on for some upcoming cool things that are happening with the podcast. So I've been working on a little bit of an enclosure, dunked on for a prize that's coming up here. So Parker's doing some stuff on it. And I've been playing with the enclosure design, hopefully we'll come up with some cool stuff that will be highly desirable or not, or not. And it's not going to be already printed. I can tell you it's not gonna be 3d printed. Yeah, it's gonna be subtractive subtractive. Printed? Probably actually.
And people have no more information about it around June 1. Ooh, it's
coming up. Yeah, no, maybe maybe by that time, we so Parker and I, well, I should say Parker already has some concept drawings of what the prize will be. Maybe by then we'll have something a little bit more set in stone.
I'm hoping when we announced whatever happens on June 1, we have kind of like this thing. Like a 3d render or this thing.
Yeah, yeah. I think that's that's the goal. Yeah. So yeah, stay tuned.
Stay tuned. And speaking that stays tuned. RFO time. Okay. Or the rapid fire opinion? That's right. Yeah. Don't leave yet. Don't turn off your radio. People still listen to radio.
Yeah. Don't turn off your thing.
Your Zune is.
Gosh, I haven't heard that as long as
all right. I got side tangent on that.
Is go for it is.
So I had my I had a colonoscopy last Monday. This is just a side dish. Okay. And so during the prep, so people don't know, because they're not old enough. You have to spend a whole day prepping. Okay. And so the basic thing you can really do while prepping is like watch movies. Right? Okay. And so I was like, Okay, I, you know, I don't really watch a ton of Marvel movies or whatever. So I'm like, Hey, I'm gonna watch Guardians of the galaxies, like the one and two. Yeah. And the second one. This one is weird. He gets his Zune though at the end. Yeah. And I'm like, What year was this made in?
Yeah, but his the whole first one is like a cassette tape. So they're just they're just walking down the line, right? Yeah.
But like after cassette, you'd have like mini disc.
Well, I guess well, you'd have CD,
or mini mini disc, and then mp3 But like, Zune, I don't even know if Zune was still around when guardians of galaxies two came out.
Well, neither word cassette players.
Yeah, but the whole thing with gardens galaxies is kind of like the 80s ish vibe. For the music.
I think they're just going down the line, and they're, they're catering to whatever retro thing was cool for some period of time.
Maybe but I don't think the Zune was ever cool.
I had a friend who had a Zune. He thought he was cool. I remember he had one of those things, and it was capable of like 20 songs, or something like that. So he was always going to his computer to swap out what was on it.
Hmm, apparently the director of that movie has an explanation of why they use a Zune, but I'll read it afterwards. I thought it was really like it. I'll put it this way. He's one that showed up. I'm like, why is that in this movie? Now? That doesn't make any sense.
You know, the part of this that I like is that it you could have still gone on that entire tangent without talking about the colonoscopy and it still would have been the same.
Well, I have to explain why I would wait six hours in my life watching those movies.
I hate the first one. i The first one was cool. The second one.
It's okay. I like I was what is what are you doing more of a tangent is because I watched those movies. And I'm like, Man, I felt like afterwards. I'm like, Man, that wasn't really a good use of my time. Because afterwards, I watched. Tarantino is Hateful Eight. Oh, yeah. And I'm like, I went from like, garbage movies for the masses. And then I then I watched like, a, like, cinematic masterpiece of a movie. Like this huge, like, gap of like, the technical aspect of that movie, The how it shot the characters, the writing, it just, that movie is just so much higher than the other one than guardians. It's just like, Yeah, I was like, Man, I wish I could watch. I should have watched The Hateful Eight, three times in a row. That's what I should have done. I you know, it's like one of those movies, you would only watch if you're stuck on an airplane. I would say guardians of galaxies is on that list.
Yeah. Well, I mean, if you're on gardening, I mean, if you had most of the airplanes that, you know, go to Europe and stuff. You could watch it six times. All the way why?
Okay, actual RFO time. Yeah, yeah, yeah. Yeah. So last Friday, there was a tariff increase may tense tariff increase. And this is the section 301 tariff list three went into effect. And surprisingly, not a lot of people are talking about this. I've noticed like there's a couple of manufacturers out there that are like, hey, PCB pricing is going to go up because of this tariff. But that's about it. It's a very stark contrast from last July's tariffs, when that one was cups coming in, like people were like, freaking out, like crazy. And this one is kind of like an okay, whatever. But the thing is, that was on last July was only a 10% increase on his huge list of things. This is a 10% to 20. This is a taking the 10% on some items, and bumping it to 25%, which is that's huge. And it's more than just some items. Yes, yeah, you're right. You're correct. It just amazes me that no one's really talking about this. So I wrote an article on it last Friday came out today. And I basically broke down what items covers it. The the first big one on the list is unpopulated circuit boards. There's actually a lot of stuff on this list. But this is, you know, only for electronic manufacturing and components. Because, I mean, we don't talk about tractors that often on this podcast.
Well, okay. Also, real quick, I can tell you that people are starting to pay attention now. Because as of today, the stock market took the biggest hit since January due to China retaliating with higher tariffs with higher tariffs. Yeah. So I mean it. The tariff itself isn't something but as soon as the money starts to get hit, people start really paying attention.
2019 tariff wars.
Crazy. So what's all on the list?
So the first one is, well, that's important for electronics is unpopulated circuit boards. Yeah. So if you import unplayed circuit boards from China 25%
Any unpopulated circuit board? Yes.
It doesn't matter what it goes into, or what it's for. 25%
I like I like what you said earlier today on the Slack channel, or at least you might have just said it to me where it was. Now those $1 JLC boards go to $1.25
Well, okay, yeah, so for Yeah, my $1 boards it's it's not huge hit. It's annoying, but for a lot of others it's it's a hike, you know,
that's a hike. Yep.
So there's a handful of electrical components diodes.
Yeah, it's not as much as last year in July last year. They were like, everything that's electrical component, pretty much a passive at least is getting a tariff, but in this is very specific of what they're choosing. Yeah. So diodes that are used for surge suppressing and like TV s and lightning, like high voltage suppressors, basically. Those are going up. And tariffs. resistors in the forms of potentiometers and reo. stats. Yeah, is going up. Very specific. It's not like just resistors. It's potentiometers and reverse. That's basically variable. resistors are going up and
yeah, but resistors proper were hit the first time around.
Yes. Yes, correct. Transformers is the big one. Yeah. And it's basically any commercial or non commercial exercise any like, generic transformer is not has 25% tariff on it.
Right. But it's a but it also says electrical transformers other than liquid dielectric, having a power hand and handling capability or capacity less than one KV A. So that's like, all consumer electronics that have a transformer in it.
Yes. Which is everything that plugs into the wall. Right. So they're not hitting your power supply. It's got a transformer in it. Yeah. Great. Great.
In for power supplies.
Yeah. And doctors actually calls out inductors that go into power supplies for what they call ADPs, which are, we'll get into that in the future ADP, machines and units of heading 8471. And we'll get to that in a little bit. And telecommunication. And then it just says, other inductors, which is everything. Sounds like they could have just done the second one, which was oh, yeah, but for some reason they call out this other one as well. I don't know why, but they do. Let's see what else is on this list. Oh, and the next the last big electrical component is batteries. But primary cells only. Okay, and so like, who plays D sells stuff like that? Those are gonna get a 25% tariff from the 10%. So expect more devices to say Batteries not included.
Good movie, by the way. That's actually a movie. Yeah. Better is not included as well. That's
the it's the documentary for toys.
I don't think it's a documentary.
No, no, I'm thinking of something different. I'm thinking of a different movie.
Go check it out. I remember seen as a kid and I loved it.
Well, that movie is. Are you talking about the 1987? Batteries not included? Yeah. apartment block tenants seek the aid of alien mechanical life forms to save their building from demolition? That's right. It's that movie is as old as I am. Need to? Sure I'll take maybe I should have watched that instead of Guardians of the Galaxy, probably you
probably would have liked it more.
So yeah, that those two batteries will go up in price that they're made in China, which probably most of them are. Yeah. And then the next big section is printed circuit assemblies that go into X, like into products that we finally assemble here. And so what I was talking about, which was machines of 8471. These are ADP machines, which stands for automatic data processing machines, which covers pretty much any thing that has a processor in it or a computer. So laptops, computers, tablets, phones, all that stuff falls under eight or seven. Yeah, falls under 8471. And so if you make a a graphics card in China, and when you import it that goes into an ADP, so it has 25% hike on it now, instead of 10%.
So okay. Your little at Sam board that you made that breakout board, that is a data processing machine, if you had that printed circuit assembly made Do you think you that would get tariffed? Not under 8471? Okay, because it's not because it doesn't go into a ADP?
Got it? It actually would not get it would get 10% Not 25%. Okay, because last July, there was a blanket pretty much any pcva has 10% on it, right? Okay, so it wouldn't get this particular right, it wouldn't get this particular one. This one is basically circuit boards that go into computers, laptops, input devices, output devices, storage units, anything related to computers, basically. Right. So
yeah, your your your raw motherboard that you buy from fries is now 25% high. Yes. Unless it was made in like Taiwan. Right, right. Oh, of course. This is this applies to things created in China. Yes.
Word processing machines and I had to look up what that was. That's electronic typewriters.
So, electronic typewriters.
Well, the thing is, I haven't looked this up, though. But the fact though is they called out in this new thing, electronic typewriters. So there is a company here in the United States that make circuit boards that go into electronic typewriters. Hmm. Okay. So someone has to be doing this final assembly of electronic typewriters somewhere.
Yeah, states. That's, that's weird.
Next thing on the list is like power supplies of machines 48471. So, laptop chargers, power supplies that go into your computer. So if you make a circuit board that goes into those things that go into 847 ones, that gets a tariff, domestic microwave ovens is specifically called out. So if you make a circuit board in China, it gets hyped. If he goes on to a domestic microwave oven. We're gonna skip some of these. What's a weird one is assemblies and sub assemblies of articles of eight, five to zero dot 90, consisting to two or pieces fastened together, which is very, very specific. But the thing is eight 520 dot 90 isn't in the current tax or tariff code. It was removed in oh seven. It's basically for mp3 players. And they just made it more they made extra ones that are more specific now. Because I guess by oh seven, there's so many things that are sound recording apparatus, whether or not incorporating a salary producing device. like cell phones fall under that too. So they made it more specific to like mp3 players and many other codes. Well, the thing is this, this this code is actually 8522 dot 90 dot 25. Still has the old eight 520 dot 90 units. So never updated this thing. They just copy paste. Yeah, copy paste, you know, some governments, you know, in turn,
oh, my gosh, this list is forever.
Oh, yes, we're gonna skip some of these. But the ones that I thought was interesting was like 8531 9030, which is electronic sound or visual signaling apparatuses, which would include synthesizers and musical creation devices. Which is something that you you build. Yeah. And so if you build a circuit board that goes into a final assembly in the United States that generate sound, boom, right there. So basically, there's a lot of like, it's interesting, where like, it's very specific of X PCB a in X, like they chose these for a reason. And so I want to guess, there is some contract manufacturer that builds pcva, that goes into microwaves. And that Senator is protecting his constituents in that state. That's the one thing I can think of is like, why is it that specific?
Yeah. It would be interesting to know who what the committee looked like that wrote all of these, and where are they getting their information from?
Because these are these tax are these tariff codes already existed? Prior? Why write these warnings is these are the ones that are choosing to increase from 10% to 25%. And even before the 10% increase last year, these have existed for decades.
Who do you Who do you slip money to be like, Hey, throw this number on there?
Might be WMD for that electronic sound and visually signaling apparatus.
Oh, geez, I can I can guarantee you Oh, this is crazy. I'm really interested to see what is the end result of this. I
mean, I get the goal. I get the whole reasoning behind why our nation is wanting to do this, but just how it's panning out seems really odd to me.
Yeah, and we talked about this last year when we talked about the the July stuff and what this really hurts is the mid range is companies and United States because they are big enough that they can outsource some of their stuff to China or somewhere else like their PCBA. I do final product assembly here. Actually some really large companies like Samsung does that here as well and like like they do TVs that way they'll get circuit boards made in China. in Tijuana, and they do final assembly a TVs and like, Austin. It's kind of weird. Yeah. But it's really, but most of these companies that do it that way, they're kind of like the middle guys, they're not super big where they can do everything in China like apple. And they're not small enough to where it makes sense to just do everything in house, right? Or do anything local. And so they're really hitting those guys. And it's like, is that really the problem? You know, hurting those guys is, is the bigger problem. The fact that your iPhone is made in China? The final product? Yeah. And I think I'm not really a big fan of this PCBA that goes into x thing. I would like, I'd like to see it like, full on like, products, right? That comes from China or actually tax because right now, that's not the case.
What do you mean?
So if you are, are, are a company that makes a microwave all the way in China, so it's 100% Made in China, and import that it's not 25%? Oh, I see what you're getting. At some other percentage, it's a lot lower, though. But they're not going after that stuff. And that's the problem. Like these pcbas, like, go into X, that at least that going into X is a US job, right? Whereas Yeah, what's what's gonna happen here is, those middle companies are going to try to either bring all the PSBA in house or to other contract manufacturers United States or into Mexico, or they're going to offshore everything, and just get a final microwave back.
I actually ordered TVs and they got microwaves. Well, and
yeah, you there's a lot of raw material, maybe not raw material, but but components that by themselves are not the final product that are on this little I'm thinking transformer and potentiometer like that, why why hit that instead of hitting final product, if things that you're worried about? Are things like copyright infringement? And, and things of that sort? I don't know, like, because this seems like it's going to impact the US public quite a bit for us to appear tough to China, you know,
it's I was talking to you about earlier is like, you know, why are they doing transformers? And us told me, We have ton, like, transformers is one of the last, like, actual electrical components that we still make.
We make that there's tons of transformer manufacturers in the United States. Tons of whereas compared to
resistors, right, like an Oh, 805 10k resistor? I don't think there's anyone that makes those in the States.
Yeah, there's still money left in Transformers. But yeah, you can't you're not going to compete with resistors. And money's in the transformer stand. Right? Right. And maybe that's why they put that on there.
Yeah, that's I'm thinking is there. Whatever committee, one guy was like, Hey, I've got a transformer manufacturer in my, you know, voting bloc, you know, let's put this in there.
Maybe, you know, who knows? Well, and with the transformer thing, they're obviously not including? Because they said non liquid dielectric, they're not including the transport unit distribution. Pole transformers. Yeah, those I mean, I don't know exactly where those are manufactured. But that's not part of this tariff list. Correct. So, I don't know. It's this all kind of stinks to me. You know, it smells bad.
It's very, this one last year, I was kind of I was okay with because it was kind of just like a blanket thing. It was like, all resistors and capacitors, blah, blah, blah, all these things? Yeah. And didn't really feel super political. And its motive. This, on the other hand, feels very political, and what they selected for the increase? Sure. That's why I don't like about it is I don't think there's going to be really any benefit to us manufacturers. For this kind of stuff. I I would say the only one in here that benefits anyone in the United States directly would be us PCB manufacturers. Right? Because that the but the thing is, we just talked about, you know, your $1 JLC PCB went to $1.25. Big whoop.
Well, but it all gets passed, right? Like, one way, it all gets passed down to the end user or the or the end customer until the end customers finally says, I'm not willing to pay this. And then and then everything breaks, right.
Well, yeah. And you got to, I think the idea is to at least from last year, it was hey, let's you know We'll make it so that buying us parts and stuff makes more sense. Yeah, kind of the idea of tariffs in general, but this is this doesn't feel that way.
This feels like an odd punishment, and I'm not sure who's trying to be punished here. Yeah, you know, I, I don't want to get too political with it.
But yeah, I would say, I'm not really seen how, like, let's say how Makerfaire benefits from this one?
Oh, yeah. Well, I mean, the thing is, okay, so great. Yeah, if someone, so if there's a 25% hike on somebody wanting to do a PCBA in China, and then they say, oh, you know, maybe I'll go over to macro fab. But now all the parts have the 25% add on them. So it's like, Well,
the thing is about that is last year's was a great benefit from acrophobia. Okay, because it was just like, because final like Amy PCBA from trying to has increase? Yeah. Whereas now, it's like very specific things. And it's like, things that go into, like really high volume, things like microwaves. Yeah, it's just like, Yeah, I think going into like, who actually was on these boards, and then go into their district and be like, Okay, do they have a Samsung factory there? Or whatever? Yeah, I know, the TV One is, like, aimed at like, like, Samsung and those guys who get boards made in Tijuana. And final assembly here. Because like that is protecting that.
Crazy? Yes, you know, we're just gonna have to let time tell on this and track it and see what's going on. Because it just seems like
from last year, ended up doing pretty good for us. But I don't know what about this one.
We'll see maybe, maybe those who are in charge know, so much more than us. I
have no fucking idea what to do. And onto the next Sarfo. Cool, Google discontinues Works with Nest program, Titan Smart Home privacy rules. Cool. So to increase the privacy of their users, Google is discontinuing their Works with Nest program, which is basically their kind of like API that allows other devices to talk to their, their network of things. And so it kind of sucks. I guess if you've already got like a working network or things like your your whole home automation is all working. Basically, Google's just gonna, like pull the plug on that nothing that your stuff is going to work anymore.
Great. Yeah, I've talked about this before.
Yes, every single time IoT comes up. The big thing isn't going to break is i f t t t, which is if then or if then then this system, it's basically a way to glue different IoT ecosystems together. Oh, gosh. And so you can make like Amazon's Alexa work with other devices that like do switches on your wall and stuff. But they don't have to be seen brands, they just had to have a kind of like an open API ish. And it's glues everything together in a web web browser interface. And I've actually used it before, it's pretty nice. But basically, the work with this program is how IFTT works. So they're gonna get rid of that. And it's going to break pretty much I think it's going to break like every single person's, like ecosystem of home automation they own.
We've been warned multiple times, you know, don't don't rely your entire system upon somebody else's servers. Because they can just switch it off at any point in time, you know, exactly.
And given that Google is really good at pulling the plug on projects. You know, I don't know why you trust them with anything at this point. I'll say this, it tomorrow, Google said, we're not going to do Gmail anymore. That would not surprise me.
That would be Geez, that would be awful.
It would be like if they say Google Docs, and we're not going to do Google Docs
anymore. But you know what? They hold the right to do that. Right? They could get it. Yeah,
but it wouldn't surprise me. I mean, a lot of people would be shocked, but I'm like, it's Google. They do this with everything. Yeah, I mean, they're gonna get rid of Hangouts.
How are they? Yep. When's that happening?
I think, fall this year. They're gonna hit notes. It's like the last piece of Google Plus
that's finally gonna get turned off. They're finally letting that die. Yeah, well, Google Plus is dead now. Well, yeah, right. But But like all of it. Yes.
Didn't hangouts thing that came out of it?
Yeah. Yeah, Google Plus was special
So next on the list is the Sony MSI X. Ns x two plus, has some pretty crazy PCB construction. It's something I've never seen before. It was on. Thomas what how do you pronounce it? Daddy? Thomas ad. his Twitter handle is engine tankard.
Yeah, Thomas Diddy, yeah, yeah. And so
he took a picture of this, this Sony MSX to which it was like a computer back in the day you could buy and it's a two layer board with a third layer, like silk screened on top.
Yeah, it's really neat, because it's, it's a very bright blue color of the solder mask. That's it somehow they deposited an entire separate layer on top of an existing layer.
Yes. It looks like it probably picks up on like open pad vias, like untended vias. Yeah. And they somehow deposited I conducted device like probably silver I'm gonna guess. Or copper. Some kind of like ink, silver ink, probably like silk screened it. Yeah. And then they silk screened the blue solder mask over it. That's what they use blue. So they have a good contrast against like, the normal green so easily visually see that? It's worth it covered it.
It looks like a really, really highly professional done green wire.
Yes. The thing is, though, if you open up that link I have there. The other side of the board is like, all just wires everywhere. soldered to the board. Yeah. It's yeah, the back actually looks pretty nice. But then the front is just like wires jumping around everywhere.
Yeah. Cable harnesses and connectors and things like yeah, daughter boards. And yeah, it's I like the the blocky silkscreen that obviously, they're chunking out different systems, you know,
yes. Yeah. Audio Video, etc. Yeah. And look at that big module
on the bottom right. That's some kind of like encased Oh, yeah, that regulator. That's been gooped. That's a Sony part. That's not going to be oh, well, yeah, that's not a power supply thing. It doesn't look like
Yeah, I wonder what that is. It's got some big honkin parts in there that has been, you know, encased for some reason. Yeah. Maybe that's the Sony magic that goes into every product.
Oh, for sure. Yeah. I love these old boards. These are fun to watch or fun to fun to kind of look at and just be like, wow, like, there's so much by today's standard. There's so much like excess going on. But that's what you had available, you know?
Oh, that's crazy. Yeah, there's a there's a battery in that same section as that gooped up board. So there's got to be some kind of something that remembers something
you learned here first. Yeah. It's not than that. Remember something? That's right. So I go check that out. That's it's very interesting construction. If someone out there knows exactly how they were built up born, I'm thinking it was like silk screened.
I'm wondering if that's I think you mentioned something like this earlier. But I'm wondering if that's something where it's like, they messed up and they're like, Oh, we forgot. Oh, yeah. 85 traces.
They already ran the boards. Or they forgot. Like it was supposed to be like a three layer board. And they forgot the inner layer.
Yeah, cuz I'm trying to Google like triple layer boards and things like that. And it's, it doesn't come up with anything useful.
If you're building a three layer board. Nowadays, the best is do a four layer board and just like have an empty layer,
give up on one of them. Yeah, yeah.
Unless you're in high enough production volume that that PCB manufacturer is actually going to, you know, do one a custom setup for you. Sure. Yeah, go check that out.
Yeah. Let us know if you know what that what that actually is.
Yeah. Why is it that way? Yeah. I think I'm more. I think, the so screened it, and I think that's how it was made. But I'd like to know why. Sure. Maybe you're right, though. It was like yeah, we have 85 corrections to do. We've already built a billion books. worth,
it actually looks like a hell of a lot more than 85. You know, actually, I wonder? Maybe Maybe I can answer. Is this. Okay, nevermind. I thought what they might have done is just print the top layer in blue ink on the bottom so you could see it. But no, that's actual connections.
Yeah, that is an interesting idea though. It would aid in, like troubleshooting work, maybe.
Yeah, right. But no, this isn't. This is like a legit layer on top of layer. Yeah,
it's interesting how and like, if you look at the bottom, there are some green wire fixes
in here. Oh, there's more than a couple.
That's true. There's more than a couple. Yeah, there's a lot of rosin residue all over that board.
Yeah. It's also coated. conformally coated. It's got a lot of goop on it. Hmm, interesting. The MX EC M S x had a Metal Gear game on it. I remember getting a an emulator for it a long time ago. Wasn't that like a Japan only? Yeah, yeah. It's a Japan only computer 1989 battle gear. What? What? A third layer on the PCB. No. No.
nuclear warheads? High D ID. Okay, next one. So go check that out. Let us know why they would have done it that way. That'd be cool. No. Next one is the last one for today is why USB three type C isn't on more computer cases. And so this is like a how cables are made in the factory. They are very handmade. Really? Yeah. They're artists in USB type C connectors. So basically, all those connections inside the cable. They're pretty much all hand done. Really? It's not a machine that
does it. I'm surprised. Yeah. So check out that video. I'm gonna have to watch this one. No, go check that
out. That was a eye opener. On why? I'm playing the video over my audio. But yeah, it's a lot of hand assembly.
Oh, yeah. Yeah, I'm kind of zipping through that year. Right. Wow. They just have like bundles and bundles of wires. Mm hmm. Interesting. Yeah, that looks like a giant pain in the butt. Yep. And we're talking. And we're talking about all this China like, this stuff should be cheap.
We didn't complain about that.
Well, also, this is just, I guess this is one company that they're going over. But still Yeah, they are have. It's still very handmade.
Yeah. It's, it's interesting. It's like when you look at cell phones, I should find the video about cell phone construction. Sure, the PCBs are very automated. But the final assembly of your cell phone? Yeah, there is a lot of hand hand on like just assembly. Yeah, putting everything together. Like there isn't a machine that does all the screws. Someone is putting all those screws in. Right, right. It's amazing. Looking at like, final product assembly. And let's say cars, vers electronic devices like cell phones. automakers have like, it's like 90% automated assembly. Like they do some final stuff. Like, it's pretty much like if they can't get a robot to do it. It's by hand. Right? Like, they will try really hard in the automotive industry to get a robot to do it. Whereas in, you know, foam construction? No, like, let's just get like 100 people to assemble them are 1000 people apart in most cases to assemble them in so trying to get a robot to do it.
Sure. So, okay, you got to just real quick scroll to three minutes and 46 seconds in this video. What what's going on with this? There is a wire stripping machine but it's got like a cut out in a cardboard box. Which which which time? Three minutes? 46 seconds. This is great. Like what is this cardboard box? Are they trying to conceal their special machine or is there like some use for this cardboard box?
It's just pulling the insulation off. Yeah, it's just you know, finally no guards.
Yeah, yeah, you stick your finger in there. It'll Take everything off. Yeah. You know, I wonder if they have that box to catch all of the little nibbles that they take off?
Yeah, that's so weird. Yeah, it's like your USPS. You know, brewery rag? Oh, mine
looked way better than that. Yeah, your viewers did,
but doesn't have a typical China yellow tape on it.
That's true. That means we have to do an entire special about that tape. Like one day we should find out where's what is that?
Like how the person who's holding all the cables has a band aid on his finger
that machine Yeah, they found Yeah, they found the guy with the least number of band aids on their hand right for this video that's great. All right. All right. Let's go ahead and close this out let's close this
podcast out because we're at over an hour Yeah.
Okay, that was the mack Feb engineering podcast we were your host Stephen Greg.
And Parker Dolan. Take it easy later everyone thank you yes, you our listener for downloading our show you've ever cool idea project or topic or you know why the Sony Ms. X two plus has crazy PCB construction. Let us know Tweet us at Mac fab at Longhorn engineer or at analog E and G or email us at podcasts at Mack fab.com. 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 to helps the show stay visible and helps new listeners find us
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