here I have a red and green 5 millimeter LED I got this an assortment of 20 LEDs
different shades different sizes from RadioShack some time ago and we're gonna
show you the characteristics of these two colors right here and how they
differ so let's get started with it right now I'm Tom Kvichak and this is
Toms Trains and Things this channel was created to help other modelers who are in
need of guidance in pursuing their dream of building a model railroad now we've
discussed Ohm's law we took a look at resistors and found out what they were
all about we figured out how to use a multimeter and now we're gonna talk
about the LEDs I got these two LEDs right here a red and a green one I'm
gonna show you a series of four different ones with four different
resistors on it and we're gonna see the difference in the lighting in it we're
gonna take check the amperage on each one of them and show you the difference
on it and give you a practical application of Ohm's law where when you
increase the resistance the amperage decreases and vice versa so let's get
started with that right now I'm gonna take these bag of assorted LEDs that I
got from RadioShack some time ago and use these in a demonstration now these
are two different sizes they're a three millimeter and the five millimeter
okay I started my breadboard right here and I put some jumpers from the the
power bus over to one two three four different lines so we could test four
different sets of LEDs at one time so we'll just
we'll just dump these out right here
okay here we go
we got two of each color yellow green and red in the three millimeter and we
got four greens for Red's for yellows and two clear in the five millimeter so
let's see what we're gonna do here we're gonna do a little experiment with the
colors and resistors what I'm doing in here is I'm gonna make a four rows I
already have three of them in there but I'm going to show you the diode or LED
itself and the the long pin is the anode the positive side and this short one is
the cathode the the negative side and what I'm doing is I'm reversing things
so the green I'm putting on the positive side and then the red I'm turning it
around because I'm gonna show you how to use the reversing switch on here and I'm
doing it just the opposite so I'm on the green I'm putting the long one the anode
on the left and on the red I'm putting the anode on the right turn
to breadboard around so you could see it a little bit better now this is the ten
twenty two forty seven and sixty eight now you're not gonna see too much of a
difference in it right now but you're gonna see a difference in the intensity
of the green and the red and because and the reason for that is every color has a
different quality to it they have a different starting voltage for the red
the forward voltage is one point eight two two and on the green the forward
voltage is two to two point three so you see what it looks like on the green
and I'll take my reversing switch right here and switch it over to the red and
you could see the difference right there and let me turn the lights out all right
there's the red and then there's the green so you can't see that much of a
difference in the green but you can in the red on the 10
ohm now these set of resistors the one most on the left is 100 ohms then
we have 220 ohms 460 ohms and 1k ohm and let's see what that looks like here
now you'll see on the green the first two you could barely tell the difference
but once you get up to 460 you could see how it's getting dim and then up to 1k
it's really dim now let's switch it over onto the red and you can see the red is
more drastic on the 1k and you could barely see any difference on this one
here it is a little bit dimmer but not much but you could see as the resistance
increases your light on your led decreases on both the red and the green
now the red another green is less vibrant than the red I think in a video
coming up shortly I'm going to show you how to use this 10k linear potentiometer
and a few resistors so you could determine the optimum brightness of your
LED for your control panel or in a building or wherever else you
want to have them so keep looking for it it'll be out pretty shortly okay I
switch them both or I switch them around so we can have both of them lighting up
at the same time so you could see the difference in intensity on here
okay now this one is with the 220 ohm resistor and you can see how much
brighter the red one is then the green and let me switch them
around on all of them so they all come at the same time now that I have all of
them turn the same way so when I flip this switch over it's going to light
them all up now you can see the difference in intensity the red is more
intense than the green but when you have both of them lit on the same circuit you
could see how much difference it makes on the circuit now this one over here is
the 1k now let me pull the red one out and show you what happens to the green
100 220 470 and 1k with the green so you can see what the resistance does with
that now let's talk about the amperage on there and let me set this up so I
could show you the amperage right now I have the circuit set up where I could
test the amperage on this green LED with the 220 ohm resistor now let me turn
this thing on right here
so it's like 0.044 okay now let me move this over to the other
one so now with the hundred ohm resistor it's 0.085 so as the resistance
decreases the amperage increases that's your practical application of Ohm's law
right there so with a 100 ohm resistor and whatever value the LED is you have
0.086 amps with the 220 ohm resistor you have 0.044 amps now I have the meter
hooked up to the 470 ohm resistor and the LED so let's see what we have right
now we have 0.023 amps you have it on the 1k ohm and now it is point zero
zero eight but anyway you could see the difference between the 100 ohm resistor
and the 1k ohm resistor now with the LED in the circuit it's point zero point
eight eight now let me take the green LED out and do it with a red LED now
with the red LED is point one zero one
so you can see the difference in the values between the green LED and the red
LED there's the green one so that's point O eight seven now let's put the
both of them together
they'll dim and is 0.101 together 0.102 we decreased the resistance because we have
the two in parallel now let me switch this over and put them in series and
we'll show you what happens now I have the two LEDs in series let me switch
these around here and I have 0.068 so we increased the resistance
by putting it in series and effectively decreased the amperage because we have
the same voltage here and what I did was when I headed off cameras up I put it on
12 volts so let me just take this and put this back over on five volts now we
have this in series and I'll just touch it on the terminal and they're a little
bit dimmer and we have point zero zero eight amps on it and you can see on
there that it is dimmer because we have less voltage the same resistance but
different amperage different voltage and now let's put it back on the twelve and
see the difference on there now I'm going to show you what happens when you
hook up an LED without a resistor in the circuit no here's to 12 volts and boom
it just goes right out that led is no longer any good I hope you enjoyed my
demonstration there and me blowing up that little LED if you would like to see
more videos like this go ahead and hit that subscribe button and while you're
at it ding that Bell I mean there you go it worked that time
but leave a comment down below and I have some more videos coming out now
this let me just see if I can get it up here
this switch right here we saw that in the last video I'm going to show you
later on this week how I soldered that together with all
those wires on there so we'll have another soldering demonstration here I
still had the power on on that and I have more videos coming on electronic
principles I'll show you the one where I soldered this and we'll discuss some
other LEDs we got some clear ones right here and we have some square ones with
four posts that are ultra bright LEDs and I just picked up the package of Pico
cheap LEDs these things are so small the wire is heavier than the LED I don't
know if you can see it there but the LED is right there where my fingertip is
that's the little LED and it gets bright so we're going to talk about a little
little bit of that and later on I am about to order five meter strip of LEDs
where you could cut them off at three together and we're gonna do some
projects with that also so keep watching and we got a lot of videos coming up on
how to hook up your LEDs and then don't forget I'm gonna show you how to hook
them up on your toward a switch machine and cobalt switch machine and as soon as
I figure out what number 3 is about because I've been playing around with it
and it just gives you a half the voltage of what you put in so I'm not sure what
their intention of was with using that as an indicator because that's what they
said it is but anyway it just indicates all the time that you have voltage on it
whenever you have a voltage applied to your motor on there so I'm gonna be
doing some more experimenting with it and fine
not what they mean by what they say about pin number three on the cobalt
classic Omega there we go right there so and until then we'll see you later on
this week with some more project so we'll see ya
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