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# college

My name is Adam Hughes and I’m studying Electronics
Engineering Technology, with a focus in Robotics and Automation. Before I chose BFIT, I didn’t like where I was going. The chair of the [BFIT] Electronics division was saying, why don’t we take a look
at Robotics and see if you like it. It’s kind of like Legos. The blocks are simple, but you can do so much with it. My biggest accomplishment here is not what I’ve done, but it’s what I can do. You get to say, “What can I build today? What can I fix today? What can I improve
today?” If I wanted to be an entrepreneur, I can build something. I know how and I had
fun doing it.

Peter Wheeler: Okay, hi. Hello again. Today I’d like to talk with you about transformers. These are not those toy robots that turn into
monster machines, these are devices used in electronics and electrical circuits in order
to transform, change, voltages, currents, and we’ll discuss it today, impedances. There’s an interesting physical situation
that occurs when you take a conductor. Let’s take a conductor and let’s put a plus
and a minus here. When you move charge, so we talk about current,
it moves for example in this direction, from positive to negative. Some people talk about electrical movements,
and that’s fine, we can even do that as well. Let me do this for a second, let’s clean this
up a little. Okay. Electrical, electrons move from minus to plus,
charge, current moves from plus to minus. Now if you’ve got current moving, for example
let’s look at the end of this conductor, if we look at that and here it’s coming at you. We use our right hand and we put the right
hand, so it’s coming at me, we put the right hand thumb in the direction of the current. What you’ll notice is your fingers will curl
in the direction of a magnetic field. You’re saying, “Okay, but is that the same
for electrical, electron flow?” Electron flow does the same things except
what you do is you use your left hand. If we look at the flow, because it’s leaving
us, I’m going to show it like this. I use my left hand, my thumb pointing to you,
guess what? My fingers also curl in the same direction
of the magnetic field. The magnetic field whether it’s formed in
your mind by current flow or electron flow, the magnetic field will still be in the same
direction. Now the interesting thing is we’re just moving
charge here. The other aspect of magnetic fields and current
or electron flow is that if a magnetic field cuts this conductor, if we have a magnetic
field cut this conductor, we will actually cause charge to flow in that conductor, or
electrons to flow in the other direction, what have you. There’s an interesting relationship between
charge moving and a magnetic field being formed, and then vice verse, a magnetic field cutting
a conductor and the charge being required to move as a result of that magnetic field. It’s a very tight interaction between these
two physical phenomena. The property that we describe in being able
to create a magnetic field by moving charge is, the property of the conductor is called
inductance. Inductance is signified by the letter, the
symbol, L. The units for inductance are Henrys. We measure inductance in Henrys, and the symbol
for Henrys is H. We notice that there’s a situation that arises
here, okay, what can we do with this? What can we do with this? We’ve got a long length of wire, we push a
charge through it. We can create a magnetic field. We know that if we have a magnetic field moving
and we have say a long length of wire, we should be able to move a lot of charge as
well. Why don’t we create a device? Why don’t we build a device here? What I’m going to do is I’m going to take
a lot of wire and I’m going to coil it up. Why? Because I want to stay tight with my device,
so if I coil it up I can make it occupy a very small space. I’m going to push, in a second I’m going to
push a changing current through this coil of wire. Here, this is a direct current, it’s just
going in one direction. What I want to do is put a changing current
through this device. As well I don’t want the magnetic field just
to be out where it wants to be, I’d like to concentrate it. What I’m going to do is I’m going to wrap
these wires around an iron core, a type of [toroid 00:04:41], bobbin let’s say. On the other side then I’ll wrap a smaller
set of wires, in this case here fewer turns, on this device. I’ve got more turns, fewer turns. Now, what I need to do is, it’s one thing
to setup the field and it stays there, but I need to cut the other side of these turns
here with my magnetic field. Which means what I’m required to put in here
is an alternating signal, AC signal. It’s like we’re going to take our charge and
we’re going to move it, and then we’re going to slow down and are going to reverse direction
and then we’re going to slow down, and I’m going to move it again, and one more time
I’m going to do this. I’m going to put a lot more charge in, there
it is, it’s bubbling out, and then I slow down and then here I’m going to put more charge
in, let’s bubble out and then slow down, and back and forth. I represented this as a voltage changing in
time, in amplitude and a time scale here. What’s going to happen? We’re going to, right hand rule if you want
to do plus and minus, or left hand rule if you want to do minus to plus, you’re going
to create a magnetic field that is going to cut the secondary turn. This side of this device, which is a transformer,
we call these primary. This is our primary side, PRI-mary, primary,
and this, secondary. We have our primary turns and we have our
secondary turns. There is a relationship between this signal
that I’m putting in and this signal that I’m going to put out, take out. In fact if I look with the oscilloscope and
this is my signal here, what I’m going to see on this side is something like this. Now you see this is smaller than this, from
a voltage perspective the amplitude here is smaller. That is because I have fewer turns in my secondary
to my primary. I could flip this around, I could make this
my primary, this my secondary, and then I’d have a small signal going in and a big signal
coming out. The thing about in and out on these devices
is that the energy in this world is finite, we cannot create anything or destroy anything,
we can only change its format, maybe light into heat and such. If we look on this side here, then our power
on our primary side is equal to our V-primary times the I-primary, power is V times I. Therefor,
this also has to equal power in the secondary, which is V-secondary, I-secondary. Now here’s an interesting, if I use this configuration
here, my voltage will go down. If my voltage goes down and this side power
has to equal this side power, primary equals secondary, what’s going to happen is my current
will go up to compensate. Power in the secondary, power in the primary
have to be the same, which is an interesting now, because if we look at the voltage in
the secondary and we divide that by the voltage in the primary, it’s the same as saying that
you had the secondary turns ratio divided by the primary. In this case here, this is a, let’s say a
two to one step down transformer, you can calculate how much you’ll step down by measuring
the voltage in the secondary, dividing by the voltage in the primary, and it’s the same
as the turns ratio. Not always present to you in a datasheet,
and we’ll show you a datasheet in a minute, is the actual turns ratio that way. There’s another way of determining turns ratio. If we go back to our inductance side here,
the fact that I’m trying to create a magnetic field, this inductance causes a small problem
in how fast the charge can move. I can put the voltage there but the charge
can’t move right away because it’s somewhat pushing to create this magnetic field. That concept is called reactance. Reactance is the pushback of the current with
respect to the voltage that’s applied. If we actually showed on a scope the different
between the two, or in a phasor diagram, we see that the voltage is leading the current. The current will catch up but the voltages
will be in front of it as we continue to change it back and forth, back and forth. Now that is reactance, but there’s another
concept because this winding, this winding too, as will this one, have a small, very
small, but will have a small resistance in it. By the way, just to clarify something, these
two are separate. There is no electrical connection between
the primary side and the secondary side, putting an Ohm meter across here will show you an
infinite or open circuit. We’re coupling our signal as a result of changing
an electrical field to a magnetic field, back to an electrical field. Let’s get back here, because like I said not
all datasheets will give you turns ratios. Reactance is the pushback to the current flow
when the voltage is applied. In this case here we have resistance, this
is pure play resistance, secondary resistance, primary resistance. The entire circuit pushing back on what we’re
trying to apply, that is called impedance. We denote that with the letter Z, impedance. If we actually then look at a datasheet, more
often than not they will give you the impedance at some fixed frequency of this primary circuit
and the impedance of the secondary circuit at that same fixed frequency. If we do this, if we take the impedance of
the primary and divide it by the impedance of the secondary, we will also get then our
turns ratio, our primary to secondary turns ratio. That’s another way of calculating. Notice this is slightly different, this is
secondary, secondary, primary, that’s this way. This is reversed as far as the impedance,
as far as what’s in the numerator and the denominator. That’s it. Reactance plus resistance is impedance, although
measured in Ohms in both cases here. Because the voltage is leading the current
in the inductor this is known as an inductor, but in the resistor the voltage and the current
are in the same phase for the resistance, then in order to calculate the two, and we
won’t spend much time on it here, what we do is we say the impedance is equal to the
square root of the sum of the squares of the resistance and the reactance. Again, I’m not really trying to cover that
today, what I’m trying to explain to is this connection from one side of a magnetic circuit,
electromagnetic circuit, to the other side. One last point before I leave this, normally
the manufacturer will put what is called a phasing dot on there, which means that if
it’s going up here, the signal on the primary, it will go up on the secondary. If you reverse your leads, what you’ll find
is the signal will be 180 degrees out of phase. This is showing in phase, this is showing
out of phase. I think we’ve got it.

I do a lot of college shows, which, it’s fun,
but you have to spend a lot of time with college kids, and you forget what they’re like
because we keep them quarantined during that portion
of their life. But they’re, oh… There’s no consequences
for college kids. You can just walk in front
of oncoming traffic like a complacent Clark Kent. They’re just adorable,
with their MacBook Pros and their wrong opinions
on things. You know what I mean?
It’s just, like… People always give teenagers
a tough time, but, like, at least teenagers
know they’re children. Whereas college kids
will just walk up, like, “What’s up? My name’s Devin,
or something stupid. “Let’s talk about the economy, even though I’ve never paid
an electricity bill.” It’s like, no. Slow down, Atlas Shrugged,
I don’t need your… I don’t know, it’s… I’m not trying
to sound judgmental. I remember,
when I was in college, I was just a terrible person. One of the worst things
I did in college was, I was prescribed to a drug
called Adderall, which you guys… You guys party, right? Yeah. (applause) I didn’t like the effect
Adderall had on me, so I decided to stop taking it, but I kept filling
the prescriptions, because apparently
there’s, like, a huge market among college kids. So I sold it,
so I was a drug dealer, but in, like, the least gangster
way possible, right? Just, like, hanging out
in the quad between classes, like, “Hey, youngblood, hey. You want to get high? Grades?” I was the only person on campus
selling it, too, which was… I met a lot of interesting
people. There was one girl who was
trying to sleep with me to get free Adderall. Attention whore. (groaning and laughter) It’s more for me than for you,
that’s fine. That’s okay, that’s okay. The thing about college is, when you’re in college,
it makes sense, but when you go back
and visit college as a grown-up, it’s crazy. Like, I realize, at this point, I don’t even know how to explain
how college works without it sounding like
I’m pitching a sadistic concept for a reality show. It’s like, “All right,
here’s what we do. “We take human beings
during the four years “we’re the most physically
attractive and sexually able, “and then we put them
in an all-expenses-paid resort “with no supervision
and limitless booze, and then see if they can learn,
huh?” To… When you’re
a no-name comedian, to get booked to do
college shows, you have to do these things
called NACA conventions. They’re these giant weekend-long
conferences where you go and you showcase
for student bookers from, like, hundreds of schools. But because college kids
are so progressive, a lot of the other acts are people who talk about how
they’ve overcome persecution for their ethnicity,
for their sexual orientation, for disabilities, and then me. And here’s the thing about me, my appearance evokes
many feelings. Sympathy is not one of them,
you know what I mean? No one wants to hear
about the plight of a guy with resting rich face. It’s just not very,
not very compelling. There’s no one in the audience,
like, “I want to hear more
about his Kampf,” or whatever it’s called,
and, uh… (laughter) Well-read crowd, all right. The thing is, for me, the contrast makes it
very challenging, because I’ll be sitting
backstage and I’ll hear the performer
in front of me come out. And he’s like,
“Hey, what’s up, y’all? “Let me tell you what it’s like being a sassy transgender
Muslim,” right? And the crowd just explodes. Like, “Yeah, you’re my spirit
mammal,” right? And then she just crushes
for 15 minutes, talking about overcoming
and then… I’m next, and I walk onstage, and even though they’ve never
seen me before, I’m how they already pictured the bad guy from her stories,
right? The crowd, not on my side,
sea of contempt, just the death glare from a thousand
gender studies majors. They’re just like,
“All right, okay. “So what’s your struggle, huh? Talk about your hardships.” It’s like, “Uh… “People incorrectly assume
I’m good at lacrosse? Like, I don’t…” You know what I mean? That’s why I’m not edgy
as a comedian. I feel like I’m just
too privileged-looking to have an opinion,
you know what I mean? Like, I can’t walk onstage
and be like, “Black people…” It’s like,
“Whoa, there, boat shoes. “No, no, no, no, no,
uh-uh. “You don’t get to have
a bold stance on race “and the keys to your parents’
lake house. That’s not how this life works.” I don’t know, I feel like,
as a white person, that whenever I bring up race, it just sounds a little bit
racist, you know what I mean? Like, I used to do
recruiting work, and they’d send me around
the country, and this one time, I ended up at a career fair
at Dartmouth College. And while I was there, I saw
this girl walking around who was African-American,
very attractive, and she looked exactly like
this girl I went to school with. And I really wanted
to tell her that, but then a voice in my head was,
like, “Yeah, don’t. Don’t say that,” right? Because, best-case scenario,
all she is going to hear is, “Oh, cute, Zack Morris thinks
all black people look the same.” Right? So it’s like… So I ended up talking to her
anyway, and we chatted
for a little while, and I mentioned
where I went to school. And she goes,
“Oh, Rice, um, long shot, but did you have a class
with my identical twin sister?” And I was like,
“Wow, that’s crazy. “I was going to say something, but I thought I’d sound racist
because you’re black.” And she was like,
“No, but now you do.”

I want you to just focus on the spinning
pocket watch right here it accounts backwards some three to one what I reach
number one I want you to just close your eyes and as soon as you close your eyes
I want you to imagine yourself still you can hear the sound of children
playing you can hear the sound of the ocean caresses against this close you can see you can see this respected with each number accounts so was it hard to find parking in
Cambridge no actually when to fry something so what kind of
mushroom have you tried from mythology how does that taste like chicken
no no just let it out let it go right now open accounts for one two three when
I count to three you couldn’t open your eyes you look into my eyes you’ll find
that all the energy or you’re nervous damaging are leaving their body through
your eyes and just feel my eyes drawing and training all the negativity training
all the anxiousness training all the anxiety you’ve ever experienced draining
out of your body through your eyes into my eyes I want to see all your enemy
train and the more energy draining out of your body and your mind and the more
exciting cocoa tree know your body and if you sleep here a sleep here yes sleep
here and when all those entering all those negativity go train out of your
eyes if you’re so sleepy that you close your eyes you go back 10 times deeper
into hypnosis one two three eyes open just look into my eyes
I just find energy inside your negativity yes find yourself just assume so things so good the anxious and I want to try this one more time but
right here three two one I want you to feel all your anxiousness and all
negativity that you maybe I wouldn’t know to scream out of your brain through
my finger I know three two opening up your mind whatever negative
emotions then you may be holding them then you may or may not know how to
describe it that’s fine it’s training hours of your mind and of your brain all
over this thing now right here you can still see my touch
right like a forehead right you

This is the Biomedical Electronics
Technology program, called BET, where we’re training students to get
employment at hospitals, and they’ll be doing equipment installation, maintenance,
and repair, and it’s a good career. Right now, there’s a shortage of BET
technicians in the St. Louis area. I get calls from different hospitals, even the
Scott Air Force base, they’re looking for biomedical technicians, and our program
here just seems to fill that need. Everybody that’s gone through the
program, that’s gotten their BET associates degree and/or certificate, has
gotten employment, and it’s all been local. It’s been at Barnes Hospital, Mercy,
the Veterans Administration, and even some of the pharmaceutical places, so the
track record is real good because the demand here is high. Someone’s looking
for a career that has a very good outlook for it in the future and don’t
have to spend a whole lot of time doing it, this would be great. One of the things I really
types of test equipment we have here. That’s the world’s best test equipment. I
came from an engineering lab that used the exact same equipment, and you don’t
see that in institutions, not even in four-year colleges, so students are
learning on equipment that they’ll actually be using on the job. See what
frequency gives us exactly seven-oh- seven [inaudible]. Oh, ok! I’ll change that. Yea, yea. Part of the training here is doing
projects, major projects, and they have to design, build, test, and troubleshoot all
these different projects that they work on, so it gets them a lot of good hands-on
experience. We solder sometimes, we build electrical circuits. We build different
stuff that we would be doing in the industry. In addition to a great staff
here of people that actually work in the field, our biomedical instructor is
actually the manager of the equipment repairing at Barnes, and the hospitals
work with us like what do we need to teach, and what do they want our
graduates to know. Coming to STLCC is one of the best decisions, I think. We have
some of the best equipment in the labs here, and also the teachers here are just
amazing. Now you want to check the input, and you’re still, you’re a little bit…there you go. I think it offers them a lifetime career opportunity that is a good career, a
solid career, and reliable, dependable. You’re doing a community a lot of good
because you’re helping people. You’re not dealing with the actual patients, but
you’re dealing with the equipment that takes care of them.

Robotics might sound futuristic, but the
technology is being used right now in advanced manufacturing. The DMACC Ankeny
Campus is training students in state-of-the-art automated systems and
engineering technology, plus it looks pretty cool. When folks here robotics
they often think of robotic arms, but in reality for us robotics for us ties
directly in with automation. That could be biomedical systems in a hospital. That
could be security systems in office and retail environments, as well as
residential. That could also be vision systems for us and office automation
systems, as well as communications. Whether they be in TV, radio, or other
avionics type environments. The reason I really like electronics is that I enjoy
troubleshooting. I enjoy finding problems and then figuring out why they’re broken
and how I can fix it. I enjoy the challenge of being able to look at a
machine that can tell you nothing and figure out everything. The other program
for us is a robotics and control system. Where we encourage the learning of
robotics, PLCs or programmable logic controllers, and applying electronics,
maintenance, technical skills, calibration, repair, and installation for the
industrial market. Both of those programs take place over approximately five terms.
We do have a summer term what we call our term three. However, I also would be
remiss if I didn’t talk about some of our other shorter term projects as well.
Students who complete approximately the first three terms can qualify and earn a
diploma of Electronics Fundamentals. Which, would qualify them for some of the
entry-level electronics positions including installation of electronic
devices. We also, rolling out in 2016 have a Biomed Technician Program specifically
to prepare students so that they could go work in hospitals, clinics, and other
biotech environments; repairing maintaining installing calibrating
electronic devices. Reason I’m interested in the biomedical field is, because there
is always going to be demand in a need for electronics technicians to maintain
the equipment that the doctors and nurses utilize on a
day to day basis. We’re indirectly saving people’s lives. Folks who enter this
career are going to have the opportunity to continuously learn. They’re also, going
to have the opportunity to continuously apply what they’re learning to new and
different solutions ideas and things that we don’t even know are out there
yet.