Hello, Columbia. Welcome to our edition of Telling Our Story, Exploring the Parks. I am your host, Wanda Austin Herndon. Join us as we explore our parks. Hello, Columbia, and welcome to Telling Our Story, Exploring the Parks. Today we are exploring the Columbia Art Center. We're going to talk to Ms. Boja Miller, and she's going to tell us all about the activities, the open studio and all the programming and camps they have going on here. So stay tuned and come take a walk with us at the Columbia Art Center. The Columbia Art Center moved from a small cramped art center at 1932 Calhoun Street to a 5,000 square feet facility at 1227 Taylor Street in October 2017. The Columbia Art Center is a state-of-the-art facility with the capacity to offer not only open studio but also multiple classes consecutively. We have about 5,000 square feet here and this is primarily pottery studio but we do anything art related really. Right now, of course, we're in the middle of a summer camps. We have planned nine weeks of summer camps all together. We're starting at ages five to fifteen. In addition to pottery, the opportunity is to learn about a variety of other arts including, but not limited to, basket weaving, jewelry making, book finding, paints, drawing, sewing, and many others. Claim making, painting, coloring, like a lot of art, what you can do in art. It's a nice environment, nice, quiet, friendly, so that's one of the things that kept me going because I've gotten involved in other activities where it wasn't as welcoming and so I didn't stick with it, but this place makes you feel welcome as well as having that, you know, opportunity to create. The Art Center's goal is to provide citizens of all ages activity and events for a great art experience. We also offer classes and workshops for adults and children all year around. Anything from very beginning introduction to pottery and handbuilding basics or beginning wheel throwing to very advanced classes like sculpture or intermediate handbuilding. It's going to be hard in the first like few weeks but in practice you can learn to get better and after a while it becomes a lot of fun to do these projects. It feels like an accomplishment that you have like something to show how much you want. We do offer open studio program as well. As of right now we have 113 open studio members. To become one of the members you would have to take one of our classes and then there's a waiting list. Waiting right now is about six months for the open studio. The Center further provides the program creative journey for military veterans giving them the opportunity to paint, draw or work with clay. This right here is an opportunity for you to build your creativity.  Because we are part of a part of City of Columbia Parks and Recreations we can afford to offer classes and our memberships for more affordable prices but also we offer a lot of scholarships as well. We believe that anybody who wants to make art should be able to do that and we try our best to make sure anybody can. This is not like when you may have a membership in a gym and you're doing your workout. When you come here and join us you become part of community and that's really beautiful. I can't stress enough how important art therapy is and that's what this has become for me and I know there's a lot of people out there with this the things that's going on in the world and whatnot that need an outlet for stress. This right here has answered a question I never knew I was asking. For more information on any of the programs that you heard about today at the Columbia Art Center please call<PHONE_NUMBER>. So thank you Columbia for joining us today at the Columbia Art Center and please stay tuned for our next episode of Telling Our Story Exploring the Parks. As with all our parks our mission here at the City of Columbia Parks and Recreation is to change lives through a culture of transformational leadership innovation and phenomenal customer service. Thank you for joining us today and please join us in the future for more episodes of Telling Our Story Exploring the Parks and remember we are Columbia.


get ready because although it's not fun to either fret or be bored it is fun when you put them both together resulting in the fretboard because the fretboard gives you something to do which eliminates the boredom and distracts you from the stuff that like you were fretting about so let's do it here we are in excel if you don't have access to this workbook that's okay because we basically built this from a blank worksheet but we did so in a prior section so if you want to build this from a blank worksheet you may want to begin back there however you do not necessarily need this workbook if looking at this from a music theory standpoint because we'll simply use it as a tool to map out the fretboard give us our scale and chords that were focused in on if you do have access to this workbook though there's currently like eight tabs down below we've got seven of these green example tabs an og orange tab and then the practice tab the og orange tab representing the original worksheet we put together in a prior section it now acting as our starting point going forward mapping out the entire fretboard giving us our entire musical alphabet in letters numbers combining the letters and the numbers having a key which helps us to change the scale we want to focus in on with this green cell that will populate our worksheets to the right giving us the notes and the scale we're focused in on as well as the chord constructions constructed from the notes and the related scale that we're working on and this section we're looking at the scale of the C major scale focusing in open position on the fretboard and the chord constructions from the notes in the C major scale starting of course with the one chord the C major chord which is on the first tab open position being defined as frets zero through three we mapped out then the 135 positions on the fretboard discussed it in detail we then went to the four chord why because the 145 is going to be the major chord constructions we mapped it out on the fretboard discussed it in detail then went to the five it also being a major chord construction then we went back to the minors to the two chord which is the D minor mapped it out on the fretboard discussed it then we went to the three also a minor chord construction the E minor chord mapped it out and now we're looking at the A minor my favorite actually and that's where we are in the practice tab to the right so we're on the practice tab to the right now the A minor is you can think of it as kind of the special one because when we look at the six chord then you can think of it as the same modal construction that we've talked about before meaning when we looked at say the two chord the D we can think of it as the Dorian mode if I try to make that my central position as I play it but that's a less common mode then when you go to the sixth note of a major scale which makes the Aeolian mode otherwise known as the minor scale and for guitarists a lot of people kind of learn the guitar in a minor possibly more than C major or any other anything else generally possibly and like G or or E minor are common are also scales friendly to guitarist a little bit easier to play as the guitar is tuned to standard tuning not that you can't play just about any normal type of scale on the guitar you basically can because these shapes are movable when we say some scales are easier to play on the guitar we're usually talking about playing them in open position then being easier possibly in part because we're utilizing more of the open strings as they play an open position but the beauty of the guitar is in part is it's symmetry so once we learn how the shapes can be moved up the neck we can utilize that to play just about any kind of scale or normal scale that we want on the guitar that said the A minor is a very common position or scale that people start to learn in and it's my favorite kind of scale so because the minor unlike some of the other modes is something in western music that we see almost as often as the major I would like to put these modes side by side so I'm going to scroll down a little bit and I'm going to hide from this cell bi to bh so we get the minor or Aeolian in here and I'm going to hide that so and I'm also going to hide this A t's to try to squish this together a little bit right click and hide that so notice uh you can see this this is the related mode for for the minor so now we have the related mode let's get rid of the yellow over here and so and then I'll make I'll copy this and say if I looked at it on the minor it would be the one on the minor and remember when we look at at the minor the one four five would be the minor notes and they happen to be and they're going to end up being the same notes because this is a mode which is the A D E here and then we have the A D E here so then I can color code this let's make this the same green and let's make this one red and then let's make this one yellow so you can look at this as we did before by thinking of the this as the sixth note of the C major scale or you can think of it as the one note of the minor over here so let's think about the fingering of this the standard fingering is going to be this and this is pretty universal pretty much everyone plays it this way for the most part right you're going to put your pointer finger on uh this C right here and then you're going to put your ring finger on the A and then you're going to put your middle finger up on the E and then the bottom string is going to ring out and you want this open A string also to ring out so you want the open A to ring out and that bottom E the bottom E isn't as important you don't even really need the A notice that this nice tight little shape right there actually has everything you need in it but we often want to utilize that nice bass note to put the to put the A in the bass if you play the top string you don't have to but you can but but oftentimes when you want to play a really A minor sounding thing you'd want you'd want to have the A as the bass note so you can mute that with your thumb just basically touching on it with your thumb so the only thing to get used to this shape sometimes when you start people do this because they want to put their they want to put their middle finger this right there it feels natural to do that at first but you'll find that when you when you put your fingers this way that where you have your ring finger above the middle finger it's a little bit too tight in there it doesn't fit as nicely you'll find it's a little bit more comfortable to put when you put this finger down it's going to the string above and then this finger is right below it and that fits a lot more comfortably I think you'll find so if you're practicing this then of course I would always start by practicing putting your your pointer finger down then your middle above the the string and then your ring and then you could just kind of practice that while you're watching tv just to get your muscle memory so you can just put your fingers down on that position once you get that position it's of course it's a really comfortable position to be playing in and it's perfect for like hammer-ons and stuff like that which is another reason I think it's a really nice position you've got these open notes remember all the open notes are kind of fair game when we're playing in the key of C major or you can think of the relative A minor same notes right and so now you've got your I think of that is kind of your pivot position and you can you can do hammer-ons and stuff really easily because you have a pretty strong type of leveraged position here so when you play this the normal position would be the A is going to be ringing out up top and then you've got your E and then your A and then your C and then the E down here then if you want to play this E up top if you hit the E up top fine because it's in it's in it's the five but you might want to mute that out as well so that's going to be the standard type of position let's make another one of these and I'm going to make this this yellow and so so once you start kind of playing around with that then you can just like we did with all the other modes you can make that the sixth note as you're playing in C major right so I can be playing and how do you do that I'm going to make the C major the home and then I'm going to add an A as I'm kind of shuffling around here right so I might go from a C to an F and then maybe I should put in my A minor and then I go back home to the C right because I'm starting and ending on the C and I'm just kind of adding the A minor as part of my C major and C is the thing I'm kind of the C is what I'm is home or you can make the A home and and that way you might want to visualize it actually as the minor mode over here the A only in mode or you can think of it as you're just playing around the six and and that's going to be easier possibly to do than it might have been when we tried to do that in some of the other modes because of in what maybe it's just because of our ears so used to the A minor mode so it's going to be it might be easier to make the A the sixth note sound like home it should be easy to do as it was for some of these other modes right like this one is going to be quite difficult you would to make because the seven chords a little bit funny but so you can so then how do you do that you could just make well I'm you're going to play the same thing but I'm going to start with an A so then that's pretty easy to make the minor sound like basically the home bass and and so and so that and then once you do that then you can start playing with the fingering in terms of what if I was to add some notes to this so notice the cup let's just look at the ways you can play this right now first you could say well I could play this shape that shape in and of itself is is easy to play and that's got everything I need right so if I was to mute everything else out and just play that I've got what I need that's nice to know because it's movable right if I move that up here I can mute everything out and now I've got a relative like D minor to this so so that's that's nice you might not need that in open position as much because it's kind of nice to bring this one out and this one out but you have that option and then you can play it like you could play it this way so I could play that thing right there and then I could reach up and add that added C up there so you could be or I could say hey I don't like my pinky reaching up like that maybe I can say I could do it this way and I can I can play this way now that's an interesting voicing oh hold on a second what a sec what did I do yeah that's an interesting voicing because the A is on the bottom so now you've got your A on the bottom remember the fifth is always there will be a fifth above the A all the time unless you're playing on this string because of the difference between that string and then you have the minor third up here so it's an interesting voicing because it's inverted so that is good to know because if you're kind of shuffling around you might you might put a different voicing in there once you shuffle back to an A right it's just because it gives you a little bit more a little bit of variance there you can also play it down here so so this would be like your standard kind of A position in an open position but notice if I was to move that up to here and look at it as I move it up I can say okay I look I can play it like that because now I'm just correct now I'm switching up my two fingers here and so that becomes movable now you can also we also said that this was movable you can also basically say that these three notes is all you really need right so I could I could do I could do just just these three notes which you might not need to do an open position as much but if again if you move that up here it would be these three notes and that gives you kind of like a higher a higher register so so which is kind of nice if you're playing like over something else so there's a lot of different ways that you can play that let's go back to the to the standard so there we have it there and then of course you could start to remember that when we look when we look at it in terms of its major the relative all the all the major scale or the minor scale around it then remember that because we're playing in a C major or a minor however you want to think of it all these open notes are legal so we'll talk more about that later but just note if you're kind of fingering it around then of course you can experiment with lifting up your fingers so I could say okay well what if I lifted you know this finger up I would be revealing a D if I did that we'll talk about that more technically later but right now I could just say well that's that's like a legal position so I could say okay what would that sound like okay and then I could do it now I could lift this one up and say okay what if I lifted this one up and that's gonna go from an A to a G all right it's kind of interesting so I could say all right that's interesting what if I lift this one up then I'm going from a C to a B right so I'm gonna say okay so I'm gonna lift up all pretty interesting variance on on on what you're playing so so that again is another thing I think it's kind of nice with the A so if you kind of just mess around with that you can you can just be like I'm just lifting up my fingers and it's pretty comfortable to do that and then you get a good feel for this position to do that the other thing that's kind of nice is you could say well I'm gonna hammer on both of these maybe from I'm going from an open position hammer boom like that and I think this is a good exercise for rhythm and it also just helps your grip better and helps your aim to get these fingers down so I'm just gonna try to hammer on I've got a very this is like again to me like an ideal kind of hammer on position right I'm I'm pivoting with this finger I've got all the leverage I need and then I'm just trying to do that and you could do it without even without even strumming just to get just to see if you can hit those strings and get them to ring out as you're as you're hammering on and you could so now I'm gonna hammer on and I'm gonna lift a string up and just do some different so you could do a lot of different a different rhythmic things and again you kind of practice your grip and it's kind of a pretty like a stress reliever type of thing it's better than the stress ball should so you could start to do that and then uh notice that I this all a lot of the shapes that we're playing we can leverage with this finger over here so it's kind of fun to try to hammer on all the positions you can leveraging on that finger so notice that I have the a here and then the c looks like this I could try to hammer on these two it's a little bit more difficult but I still have my leverage finger so I can go right I'm just kind of and then you could go to uh the the g's a little bit on f you could play the f like this but I usually play it like this when I'm using this fingers so you could try to let you can try to hammer on those fingers right which is a little bit more difficult but again it's good workout for your hands or you could try all three but I'm really trying to hit those two right and then the g's a little bit more difficult because I could try to play it this way and hammer on these two and that allows me to keep in the same position so all right and so that's kind of fun to do that and you can't really do it on the on the d minor because then you have to move your pivot position but you could move your finger down here it's not the not as easy to do the e but it's pretty fun for me so I like to shuffle you could do the e minor here too which I skipped didn't I where was the e minor I don't even have to pick this finger up you could because but if I just leave it down there I'm not strumming that and even if I do it's in the key anyways like so it's kind of a fun little thing to to play with with that with the hammer-ons okay so there is that now if I wanted to move this up let's go down to uh to here and let's say we were to move this up so I'm gonna unhide right click and unhide and then I'm gonna hide let's go from like 11 I'll try to give us much space as I can right click and hide so now if you if you move this up again you can think of it as the sixth note of the c and so if I'm starting here on the sixth note of the c then I would go around the horn to the next minor chord around the circle so until I get to a d now when I follow this shape up it's a little bit tricky because you're probably this is the root note that a but I'm because you're not playing that I might not play that a I might just play this shape would be the easiest thing to move up so I'm gonna use this note as my lead note and I'm gonna say where when do I hit on that string a d so I'm gonna say okay I'm gonna hit a d up here when I get to fret uh seven one two three four five six seven so I can go boom and I can play that shape now I'm gonna try to mute everything like I could try to play it this way so I can still pick up the d here and that's your that's your normal kind of bar chord and and that's your standard on when you're starting on the second string bar chord but you might just play it like this which is the which is you know the easiest thing to do and mute this string with the with the meat of this finger and that I'm muting up here and I'm muting the bottom one like with my palm or your pinky or you can do and do the the full bar chord so when you do the full bar chord you want to you want to mute this top string have your finger down here and then these two fingers and you have to get all the way down here uh with the bar chord this one's actually a little bit easier to play you have to get to that third in order for it to be a bar chord but because you're actually fingering that third it's pretty easy to get that one to ring out so it's kind of a pretty easy bar chord it's actually easier than than like the minor bar chord when you're playing up here but because you can ring that third out but you could just play it like that and then I could play it with just like these three notes right so if I wanted to play if I was playing it here and I moved it up to here I could say okay now I'm gonna go do do it and I'm just gonna play those three and move that up and that's kind of nice because it's higher on the register if you're playing over something else or I can add this shape and then just add this note down here so instead of playing it like this or instead of playing it like this I'm basically just taking apart this bar chord right so this bar chord is like the a bar chord up to here taking it apart instead of me fingering this one and this one down here with the bar I can just put my finger down here directly right or I can say instead of fingering this whole thing these three fingers have everything I need and they're easier to finger by switching my fingering to look like that or I can say okay this this one this one and this one have everything I need so I could more easily finger that this way and just get the top of that register all those are are useful to know it's not like you it's not like cheating it's not like well you could have played the bar chord but now you just played this three note thing down here and so that's like because you're lame that's no I mean there's there's reasons why it might be easier or better to play this in certain situations than the full bar chord right so so um so I used to think it was lame you know because I don't know when I first learned it's like well I'm it's why it's because you can't play the whole bar chord that's why you're doing that and it's like well no there it's perfectly fine to play that one of that okay and then if we moved it up again we would go from the D up to the E so I can move it from here to and I'm looking again at this string moving it up to an E and then again you can play all those shapes up here as well so whether you're playing in the key of C and using makes it in the A you could then move this up and move it back or if you're playing in the key of A minor whatever you want to do on that now it's probably better to actually look at this in terms of its minor if you look at it as the minor because now I'm just making that six the one and that's kind of easier to see sometimes because now you're just looking at it as the one four five so now the one right you could you could uh so that's that's a common way to see it so with all these other modes when we play these other modes off of these other notes we also compared it to its minor scale we don't have to do that here because we're looking at the minor we're looking at the minor uh scale here because this is the relative minor of the C major chord okay so that is that so next time we'll go into it more detail talking about it in relation to the pentatonic and major scales which these two scales again you can think of them as either C major pentatonic and major scale or the A minor you know pentatonic and major scale in terms of the notes that are in it and then we'll discuss the intervals so let's go ahead and hide some of these cells again so we're ready to roll next time I'm going to roll you can't you got to be all tucked up and ready to roll uh so we have to hide some of that stuff because the too much my legs are flaring out over here or something I can't roll unless we're unless we hide unless we tuck and tuck those legs in okay


A triple threat here from the Open Electronics Lab. Three presenters, and they're going to give us an overview of their development of open hardware and transitioning from getting into that into some really awesome hardware that they have developed and that are available for people to look at work and use. So please give a warm welcome to the Open Electronics Lab. Thank you. So I'm Eric. With me is Kendrick Shaw and Ace Medlock. We're the repository admins of the Open Electronics Lab. And when we got started in 2011, we were a lot more novice than we are today. Perhaps like some of you, back in 2011, I had never done SMD solder work ever, never done any surface mount. I looked at the multi-layer boards, and I felt really pretty like that end of stuff was outside of the realm of hobbyists. I do a little bit of through-hole soldering. That's kind of it. But then there was this really interesting chip that came out. It was only available in an SMD package. And we thought, well, OK, maybe we can build a breakout board for it, so a single thing we can do for that. And sure enough, we were able to do that. I only screwed up one board in the process, so it wasn't too bad. And from there, we went all in on the surface mount. And we built something that we weren't just getting EEG signals on, but we were able to get ocular signal and EKG and muscular things. And we were even able to control a mouse pointer using our mind. It was pretty neat. And people started asking, hey, can I get one of those? But these things were big. They were difficult to build. We didn't know enough about putting test points on, to modularize your design, to make it easy to debug. And so we said, no, we don't want to be in the business of testing this stuff. So we designed something that was a little bit more accessible. So something that you can build yourself and or you can have somebody fab it for you. It's pretty straightforward. It's not super expensive. It sits right on top of an Arduino and you can play with driving your quadcopter, whatever. And that got people interested. And one day Robin from Hamentin joined our session. And he gave us the insight that in the low resource environment, some poor countries in Africa and such, what's killing their devices is not what I expected. I expected humidity and dust and things like that. He said it was bad power. And so we started thinking, well, maybe we could build a device suitable for that environment. So how do you get from where novices to we're going to build a piece of medical equipment? Well, there's a lot of false tools out there to support you from the novice through your growth and your experience. And I think the Arduino boards are a great place to start. And there's all sorts of tools to get you going. KeyCAD is what we started with. And as we've grown everything we've been wanting to throw at KeyCAD, it's handled for us. We do some fairly complex schematic design, obviously. And then here's like a six-layer board. And by the way, if you're doing any board design today, I really recommend using four-layer boards. Because any time I'm trying to go diagonal across the board, I don't want to try to sneak around all the components. I want one layer that's just horizontal, one layer that's just vertical. I via down, go over and up, pop out, and then I'm there. Really saves time on my layouts. And then also I recommend doing some yourself, hand-do some yourself. But it's not that much expensive to get them pre-populated. And you can get them with combinations of through-hole and SMD two-sided. This thing is everything except one component. And that way that, yeah, OK, I have to do the vroom chip ourselves. But that's not a huge time investment. The Arduino build environment, no matter how novice you are, you say, I'm not a C coder. I don't do embedded dev. This is a great place to start. If you've done any development whatsoever, they've really made it fairly easy. Now, as you get more experience, you may move away from this tool. You may use more, you may like your different libraries and such. But in terms of early prototyping to this day, we still reached to this first when we're playing with something new, because it's so quick and easy to get up and running, get something going. And then another tool that we really have enjoyed using is OpenSCAD. I'm not an artist. I'm not going to draw beautiful things in whatever the art programs are. But I am a developer, so I want to be able to programmatically describe this is the shape of the thing and have it render. And then have one of our other collaborators print it out for us. So that's a little bit about how the tools are. And I'll hand the mic over to Ace, and she can talk about soldering. Thanks. So as Eric mentioned, when we started out, we were really pretty intimidated by doing surface mount soldering. And so we designed a board that had only one chip on it that had needed surface mount soldering. And we got on YouTube when we took a look at some videos and saw how other people were doing it. And that actually made us pretty bold. As Eric said, second try, which is not too bad. And so our next board, we decided we wanted to reduce the noise, which meant that using all surface mount components. Now, surface mount components are pretty tiny. So the way we decided to approach it is by using solder paste. So solder paste is kind of sticky stuff. You put it on the pads. You stick your component down to the pad. You heat it up with a hot air gun. And then the components soldered on. So that all seems pretty straightforward. But when we tried it, we discovered we had a lot of bad solder joints. It didn't actually work that well for us. Now, my background is in medicine. And when I have to diagnose a problem, I like to get a good look at it. So I stuck it under the microscope. And what I found was this. So when you look at solder paste under the scope, it's made of these tiny little beads. So there's a little solder beads stuck together by the paste. And when you heat it up, you get something like this. But you can also see it melt, but still get something that looks like this. Now, does this conduct electricity? I don't know. But in some cases, it appears it doesn't. And so for us, for me, that didn't work real well. So the way I do it nowadays is I do it under the microscope. I do it under a dissecting scope. So I just put the board under the scope, heat up the soldering iron. And when you do that, it looks about like this. Now, the trick is to get a little bead of solder on the end of your iron, because the iron itself is too big to make a good connection between the pad and the component. But the little solder bead, the solder is a great conductor of heat. So you can stick that right on there, heat it up, get your solder. Then you just pull the iron away and do the other side. And then you're all done. Now, you do get some pretty ugly-looking solder joints sometimes, but that's okay, because the job of a solder joint is to conduct electricity, not to look beautiful. So you'll make some modern art, and that's all right. I mean, you can do some really tiny parts this way. This is a 0201 capacitor that's hand-soldered. This is the same magnification as the solder paste that we saw earlier. And the nice thing about that is that you learn to be bold about being able to fix your mistakes. So this looks great, looks beautiful. I didn't solder it. But the problem is that the pads are in the order GGS and the feet are in the order of GSD. So that's not so great, but that's no problem.  And so, well, what about if you forget a component? Why, you know, you're designing, so you forget to put something on. Well, that's not a problem either. You can just do some green wire fixes and those through-hole components make for great green wire fixes. What if you accidentally put a tray somewhere where it doesn't belong? Well, you can fix that too. You get out your exacto knife and cut through it. You can even, if you have both problems, you can even lift up one of these little feet and hook a green wire onto the little foot, but sometimes you're gonna break off your little foot when you do that. And if that happens, you can just dremel into the chip and stick on a green wire. So you don't really have to worry about that either. If you make, you'll make mistakes, you will, but you can fix them. But it's also good to anticipate errors and that's what Kendrick's gonna talk to you about. So much like testing, a little time spent thinking about safety can save you and others a lot of pain in the future. So we're gonna talk a little bit about that. So the first step when you're thinking about safety is basically just take a moment to think about what could possibly go wrong. And if you have any real imagination, you'll come up with a very long list of things that could go wrong. From there, next ask yourself for each of them, how serious are they? A lot of them might be pretty minor. Some of them might be life-threading, especially if you're building medical electronics. Then finally ask yourself, or sorry, next ask yourself how likely it is. And again, this can vary dramatically. You don't have to solve every problem that's out there if it's unlikely to happen.  You might not need to spend a lot of time worrying about it. So then once you have that amount of harm and likelihood of harm, then from there you can calculate out a risk or approximate a risk. There are formal design methodologies you can go through this, but the main idea is you just combine the two and come up with in your mind, is this an acceptable level of risk? And what's acceptable can vary quite a bit. Somebody going out there, free climbing is taking on a lot of risk and they know they're taking on a lot of risk and they're doing it because it's fun. You can do the same thing in your hardware design as long as you're aware of what the risk is and you've chosen to assume it. And same thing with in a medical environment, for example, a defibrillator is a device designed to stop someone's heart at the press of a button. This is an inherently dangerous device because if you do that at the wrong time, it can be life-threatening, but it's worth the risk because if you do it at the right time, it can save someone's life. If the risk isn't acceptable, then you start thinking about mitigations and basically you can reduce the likelihood of the event or reduce the severity of the event. So for example, if you have a pacemaker that you worried about someone hacking into, you could always remove the internet connectivity from the pacemaker if you don't really need it and make it a lot safer. Take away functionality in the process or you can decrease the severity. So for example, if you have a life-saving device and it can fail in a catastrophic way, making it fail loudly rather than quietly is something that's more likely to attract attention and bring people in to fix it. So for a lot of our devices and typically for medical devices, one of the common things we worry about is electrical shock. You may think, oh, you're dealing with five volts, no big deal, we touch five volts circuits all the time, don't feel anything. Important thing there is that's with dry skin. Here we're attaching electrodes and it turns out that it's current that matters more than voltage for the risk of these things. So for example, pacemaker typically runs at about one to two volts for triggering heart beats. So these aren't very high voltages and they're relatively low current where it's kind of tens of milliamps to the skin, tends to low hundreds and literally tens of microamps to the heart. And if you have an IV in or things like that, then you can end up with very low currents, sorry, very low resistances. These can show up in the obvious way as far as flowing in one electrode in your device through the heart and back out through the other electrode, but it can also be something a little less obvious, like maybe through an electrode in your device, through your heart, to something like a water faucet that you're touching, or even less obvious than that, maybe you're hooked up to another device that's malfunctioning and if your device will connect through you to ground, your device can lead to, and your device can contribute to a shock. And although your next of kin might blame that malfunctioning device, you'd rather be around to blame the device yourself. There are a lot of things you can do to mitigate this, so you can simply, and you'll notice those last two cases, you're connected through the ground, which means both devices were plugged into the wall, you can unplug from the wall, run your device off of battery, or use isolators. Nowadays, you can cheaply buy isolation that will, power isolators and data isolators as far as optocouplers. If you do that, you wanna make sure there's gaps, which we talk about as clearance between the isolated parts and gaps across the surface of the surface board, and off the surfaces, because surfaces can get moist or dirty, and so that distance is usually larger. There are a lot of standards, but eight millimeters is usually a pretty good rule of thumb, and it's on the safer side. We'll skim over this because we're running out of time, but the important thing is, there are standards for how much current your device can run through a person. They are very low numbers, and you have to think about not only what can it run through when it's working properly, but what happens when things start breaking, which is another area to think about. So if your amplifier, the chip that you have is your amplifier shorts out, and that high impedance connection to the patient, now somebody connects the patient to voltage and ground, what do you have protecting the patient? And for an example like that, typically you can just put in some resistors in the leads leading off to the patient to make sure that total current flowing through in that failure case will be less than the safe amount of current. So with that, just wanted to close. Basically spend a little time thinking about safety. It's not hard and can go a long way. You have a lot of great tools for getting into electronics and open source hardware. Don't be intimidated. Just get your feet wet, jump in, and you'll get better as you go. And happy hacking. And then we have a number of references up here for you. I'd say that so far this is the best presentation I've seen in the program. We're glad you enjoyed it. Thank you. I reacted so frankly when I saw the first test during the things on the scratch on the SMD. I really have to congratulate you for your creativity. And at the same time, I don't understand all the things about that because some projects needs to be done or to have a very early test. And this day can be probably a Sunday. So you can get a new SMD or a vector of stuff. We typically work on Saturdays. Not a great day. Sure, yeah. So the question is, where do you get a dissecting scope? And the answer is, of course, the internet. So this is not really a special dissecting scope. This is actually just the cheapest one that had an arm because a lot of the scopes have a platform where you're supposed to set your specimen and you will burn that platform. So don't get that one. Get the one with an arm that comes out and then you can set your board on something that's heat-resistant. How much did you pay for that? It was about 300 euros, I think, to 250, 300, so. Yeah, so Kendrick actually uses one of those. I prefer the analog version. So that's actually the... Speaking and I can repeat the question. So he's showing us a version of our board, which is great to see. And the fact, I believe you're pointing to the two DC to DC converters on the bottom for our galvanic... Yes, that is an excellent question. This gets down to the idea that, especially if you're doing an ECG, someone may attach a distributor to the patient and put 5,000 volts or more through the patient. You don't want that getting to the person at the computer or other operators. So you want to have good isolation between the patient side and the side that the computers are on. So that gap there is making sure that we have that eight millimeters of distance between any metal part on the board on the isolated and non-isolated side. And there's two of them which reinforces. Yes, so we want to make sure that any component can fail. The data isolation, we have a single one because it's rated for reinforced isolation. So it's rated to be as reliable as two pieces of equipment normally. Then we have two, on the other side, we have two power isolators, such that if one of them fails, the other one is still providing that 5,000 volts of isolation. Okay. A follow-up question? Yes. Are you pacing nowadays? We are not pacing at the moment. We may add that to our list. We've talked about it. Yeah, lots of more follow-up questions offline. Okay, great. There's another question. You've survived the opalation? Yes. The question was, did the dremel chip survive the operation? And yes, the dremel chip did survive the operation. And just to be clear, this is where the wire would go into the plastic case before it goes down to where it's wire bonded to the chip. So it's not soldering directly to the chip, but it's soldering to the lead going inside the plastic case. Well, no. Thanks. Thank you so much. Thank you.