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Current time:0:00Total duration:8:56

Video transcript

okay so in this video we're going to connect our LED lights the LED lights are going to be used to test various parts of the circuit and they're also used as eyes now LEDs are polarized which means it does matter which direction the power flows through the leds leds usually have one short leg and one long leg the long leg is usually positive and so we want to make sure that we match up our two long legs together if we connect a short leg and a long leg together it will have problems they won't work the way they're supposed to so we're going to look for our two long legs once we've got those two long legs figured out we're going to bend them out so that we can connect them together and so we're going to display those two legs there on the LEDs and now that we know that there are two positives together we're going to twist them together just twist them around wanting one another and we want to make sure that the twists are very tight so that we have a really good solid connection so just keep twisting those LEDs until those legs until that's there they've been twisted around each other probably about between five and ten times so then we have the negative legs of the LEDs on the outside and the positive is TWiT the positive legs are twisted together on the inside so now what we need to do is we need to connect the LEDs to the switches and the way we're going to connect the LEDs to the switches is we're first we're going to take some of the red wire that we had in our kit and we're going to strip off about a half of an inch of that red wire and we're going to feed that red wire through the top connections there's little tiny holes on each of those connectors on the back of our switches so we're going to try and run this wire through those holes and it's this is probably the trickiest wiring part in the entire bot because it requires a you have to kind of bend the wiring out in a sort of a large loop or a hook shape to get to go through both of the holes in in each connection so that's why we've got our trusty needlenose pliers there and it does take a little bit of doing but you can get it you can get it to go through both of those holes in it it does help to make sure that the connection will be a be a good one so there we go we got the wire to feed through both both holes there so then I just bent the wire up at a 90 degree angle to the connector that it's going inside of they'll zoom in here just a bit to sort of make sure you can see what's going on and in order for this particular spout bot build to work we have to make sure that those wires are crimped or bent very tightly against the contacts if there's a lot of space in between the wire and the contact the bot may not function the way we want it to so we're taking our needle nose pliers and getting it in to those tight spaces between the wire and the contacts and bending those wires tightly against the connections and we're going to use our LEDs to make sure that that connection is actually a good one and that power is flowing so the next thing that we need to do is we need to trim our wire down just a bit so we're going to cut about two inches off of our wire it should the wire that's remaining should be about an inch and a half long and we're going to take off about a half a half an inch of insulation from that wire so just that's again it's a 22 gauge wire so it's really narrow so we use the smallest hole on our wire stripper and these are really low cost wire strippers so you have to twist them a little bit to get the insulation to come off okay so now we have our red wire there we also have the red wire coming from our battery so what we need to do now is we need to connect our red wire from our battery to the red wire we just connected to our single-pole double-throw switches so we're going to make this wire have we're going to take a little bit more insulation off of this wire so we also made it a little longer so it's about two inches long and we're going to take about 3/4 of an inch of insulation off of this wire with our wire strippers and you've got to be careful because this is a stranded wire it's not solid so it's easy to break the strands when you're stripping it so you want to take take your time to pull the insulation off carefully so that you have all those electrically conductive strands still connected so then we're going to take those strands I'm going to take that wire and we're going to wrap it around the solid core wire which is the one we just connected to the switches and with the the better the best connections are really tightly wound so we want to make sure that all of those strands are very tightly wound around that solid core copper wire there and so that's going to make it easier for us to connect the positive side of our battery to our LEDs and to other components as well so now we're going to take our LEDs and we're going to connect the resistors to the LEDs the resistors prevent the LEDs from taking too much current and burning out so again we're going to put the resistor leg at about 90 degrees opposed to the LED leg and then we're going to just wind it around the LED leg and we want to wind it around at least four or five times if not more to just make sure we've got a really solid contact connection with that LED leg and again that's the negative leg and the resistors can go on either the negative or positive lake but in this in this video we're doing we chose the negative legs which are the outside ones so again just twist it all the way around until it's nicely nice and firmly connected it's important that those loops that we make with that a resistor leg are very tight and firmly attached to the LED leg okay so now that we have our LEDs set up we can begin to connect them to the red wires which we just wound around but before we do that we're going to just test to make sure everything works let's move it here so you can see it okay there we go yeah so we're getting power through the wires and we'll try the other side this just makes sure that we've wired our LEDs correctly okay so we have and this is a low enough voltage circuit and low enough current circuit that we can we can just use our hands to connect these these things okay so now let's connect our LEDs now that we know that power can flow through there we're going to wind our try and wrap the wires from our red wires around LED positive legs which are the center legs there so we're going to try and twist everything together and this may be a little difficult so if it is you can always take your needlenose pliers and just crimp it on there and and make sure that the wires are connected tightly now the better this connection is the more likely it's going to be reliable so it's really important to make sure that that connection is is solid okay once we've got those wires twisted together and our LEDs are there we can take a piece of aluminum foil and wrap it around just to help ensure that the wires are going to stay solidly connected and they conduct power now you don't necessarily have to use the aluminum foil it's just an added precaution but we basically it allows to make sure if there's any loose wire connections there that we still get electrical conductivity but again you don't necessarily have to have that okay so now we're going to take some insulating material which will be dr. I should say electrical tape and we're going to wrap it around our aluminum foil and the twisted together wires and that should help to hold everything in place so that we have a reliable connection and it's just a little bit out of the screen there we go moving in back into the screen and you want to wrap that electrical tape as tightly as possible around that connection to help hold everything snugly in place so now what we're going to do is we're going to connect our resistor leg and our black negative wire from our batteries to the to open terminals on our switches and depending on which terminal you connect it to you'll the switch will turn it on or turn it off and so one thing you want to be careful of is you don't want to leave it on there too long because you can uh when it's turned off you can actually short the circuit and that will cause the wires to heat up but it does allow us to test the LEDs and to make sure that all of our connections are good and they are so we're going to hot glue the red wires which are the positive terminal wires and that will keep them from moving around and hold them against our double single pole double throw switches they're at