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Step 4Wire the Circuit
Preparation
Use a work surface that is large enough to support the length of the vinyl strip - this makes it easier to keep everything in place as you work. You'll want to first make the circuit with mechanical connections - no solder yet. At each connection, twist the wire or leg coming from the resistor or the LED around each other.
Lay the vinyl strip on your work surface and use it as a guide for placement of all parts. I started wiring at the bottom of the strip for no particular reason, but I think it makes sense to work from one end to the other so you keep one perspective on the positive and negative ends of the LEDs and the wiring. As you work, insert the LEDs into the appropriate holes in the vinyl strip. This helps stabilize the circuit and it ensures correct placement of the resistors and LEDs.
Long Red Wire
I considered the parallel part of the circuit to be the backbone, so I started by cutting one long red wire for the positive side of the parallel circuit. This should be about a foot longer than the vinyl strip so that you can connect it to the battery and have enough slack to drop the battery into the bottom of the pants front pocket.
First LED
I connected the 270 ohm resistor to the bottom of the red wire. It doesn't matter which end of the resistor you connect. I wrapped the bald wire around the leg of the resistor and then wrapped the remaining portion of the resistor leg around the wire. This results in a good mechanical connection which doesn't easily come apart. Use the needle-nose pliers to wrap the wires and legs - it makes it much easier.
I then connected the other end of the resistor to the positive lead of an LED using the same method of twisting the resistor leg around the LED leg and vice versa. Generally, the longer leg on an LED is the positive lead. You can check this by looking at the LED closely. The smaller plate is the positive plate. You have to get this right for the circuit to work.
Series Circuit
Next, I connected the first of the six series circuits of my complete circuit. Since each of the series circuits used two LEDs, I skipped one LED hole and prepared the long red wire for the next connection.
I needed to remove the insulation from a short section of the red wire (about 1/2 inch long). Placing the red wire close to the holes in the vinyl strip, I used the wire stripper to pierce the insulation at the top and bottom of that 1/2 inch section. I recommend you try this first on a scrap piece of wire so you know which portion of the wire stripper cuts through the insulation without also cutting the wire. Once I had pierced the top and bottom of the section to be stripped, I used the single-edged razor blade to slice through the insulation lengthwise. This was easier than I expected it to be - the razor blade slides between the individual wires of the stranded wire if you push too hard, so you don't have to be as careful as you do with the wire stripper. Pick at the insulation with you fingernail and pull it away. It may take a minute or two to get it all off, but I found that preferable to accidentally cutting the wire. (Note, if you inadvertently cut the wire when removing the insulation, just cut the wire, strip the insulation off the ends you just cut, and connect by twisting around each other. You can see one of these connections in the eight photo.
For the series circuit, I needed an 82 ohm resistor. I wrapped that leg around the bare wire I just exposed. Then, I connected the other leg of the resistor to the positive leg of an LED, just as before. I then connected the negative leg of this LED to the positive leg of the second LED in this series circuit.
I connected the remaining positive sections of the series circuits. This constitutes more than half of the work in mechanically connecting the circuit. Yay!
Long Black Wire
For the negative portion of the circuit, cut a piece of black wire the same length as the long red wire. Similarly to the red wire, place it next to the LEDs that are now sitting happily in their holes in the vinyl strip. Determine the right location to strip the insulation off the black wire so you can wrap the negative ends of the LEDs around the bare wire to complete the negative part of the circuit. Wrap the negative LED legs around the bare wire.
Note for my complex circuit with combined parallel and series portions, only every other LED connects to the black wire. The remaining LEDs connect to the red wire. If you are smart and choose an even number of LEDs, you'll have a straightforward parallel circuit that looks like a ladder and every negative LED leg will connect to the black wire.
Battery Connector
Last, connect the red and black wires to the 9 volt battery snap connector. Strip the insulation off the ends of the snap connector wires and the red and black wires. Note that the wires on the snap connector may be a different gauge, so you may need to use a different portion of the wire stripper to avoid cutting through the wire.
Test the circuit
You should now have a complete circuit connected mechanically! Turn the vinyl strip over and check the LEDs to make sure you've got the positive end correctly positioned. Trust me, even though I thought I was being careful, I still got two connected backwards. Since you haven't soldered the circuit it, it's easy to fix any errors. Now it's time to try it out and hope it works. Strip the insulation off the ends of the tops of the red and black wires. Touch the red wire to the positive end of the battery and the black wire to the other end. Your lights should come on. If not, check your connections to make sure they are good and check the polarity of the LEDs again.
Success
Whew! I can't tell you how happy I was when I finally got my circuit to work. As I mentioned, I'd never wired a circuit before, so it took about 5 attempts before I got it right. I'm hoping this Instructable will help you avoid that frustration.
Use a work surface that is large enough to support the length of the vinyl strip - this makes it easier to keep everything in place as you work. You'll want to first make the circuit with mechanical connections - no solder yet. At each connection, twist the wire or leg coming from the resistor or the LED around each other.
Lay the vinyl strip on your work surface and use it as a guide for placement of all parts. I started wiring at the bottom of the strip for no particular reason, but I think it makes sense to work from one end to the other so you keep one perspective on the positive and negative ends of the LEDs and the wiring. As you work, insert the LEDs into the appropriate holes in the vinyl strip. This helps stabilize the circuit and it ensures correct placement of the resistors and LEDs.
Long Red Wire
I considered the parallel part of the circuit to be the backbone, so I started by cutting one long red wire for the positive side of the parallel circuit. This should be about a foot longer than the vinyl strip so that you can connect it to the battery and have enough slack to drop the battery into the bottom of the pants front pocket.
First LED
I connected the 270 ohm resistor to the bottom of the red wire. It doesn't matter which end of the resistor you connect. I wrapped the bald wire around the leg of the resistor and then wrapped the remaining portion of the resistor leg around the wire. This results in a good mechanical connection which doesn't easily come apart. Use the needle-nose pliers to wrap the wires and legs - it makes it much easier.
I then connected the other end of the resistor to the positive lead of an LED using the same method of twisting the resistor leg around the LED leg and vice versa. Generally, the longer leg on an LED is the positive lead. You can check this by looking at the LED closely. The smaller plate is the positive plate. You have to get this right for the circuit to work.
Series Circuit
Next, I connected the first of the six series circuits of my complete circuit. Since each of the series circuits used two LEDs, I skipped one LED hole and prepared the long red wire for the next connection.
I needed to remove the insulation from a short section of the red wire (about 1/2 inch long). Placing the red wire close to the holes in the vinyl strip, I used the wire stripper to pierce the insulation at the top and bottom of that 1/2 inch section. I recommend you try this first on a scrap piece of wire so you know which portion of the wire stripper cuts through the insulation without also cutting the wire. Once I had pierced the top and bottom of the section to be stripped, I used the single-edged razor blade to slice through the insulation lengthwise. This was easier than I expected it to be - the razor blade slides between the individual wires of the stranded wire if you push too hard, so you don't have to be as careful as you do with the wire stripper. Pick at the insulation with you fingernail and pull it away. It may take a minute or two to get it all off, but I found that preferable to accidentally cutting the wire. (Note, if you inadvertently cut the wire when removing the insulation, just cut the wire, strip the insulation off the ends you just cut, and connect by twisting around each other. You can see one of these connections in the eight photo.
For the series circuit, I needed an 82 ohm resistor. I wrapped that leg around the bare wire I just exposed. Then, I connected the other leg of the resistor to the positive leg of an LED, just as before. I then connected the negative leg of this LED to the positive leg of the second LED in this series circuit.
I connected the remaining positive sections of the series circuits. This constitutes more than half of the work in mechanically connecting the circuit. Yay!
Long Black Wire
For the negative portion of the circuit, cut a piece of black wire the same length as the long red wire. Similarly to the red wire, place it next to the LEDs that are now sitting happily in their holes in the vinyl strip. Determine the right location to strip the insulation off the black wire so you can wrap the negative ends of the LEDs around the bare wire to complete the negative part of the circuit. Wrap the negative LED legs around the bare wire.
Note for my complex circuit with combined parallel and series portions, only every other LED connects to the black wire. The remaining LEDs connect to the red wire. If you are smart and choose an even number of LEDs, you'll have a straightforward parallel circuit that looks like a ladder and every negative LED leg will connect to the black wire.
Battery Connector
Last, connect the red and black wires to the 9 volt battery snap connector. Strip the insulation off the ends of the snap connector wires and the red and black wires. Note that the wires on the snap connector may be a different gauge, so you may need to use a different portion of the wire stripper to avoid cutting through the wire.
Test the circuit
You should now have a complete circuit connected mechanically! Turn the vinyl strip over and check the LEDs to make sure you've got the positive end correctly positioned. Trust me, even though I thought I was being careful, I still got two connected backwards. Since you haven't soldered the circuit it, it's easy to fix any errors. Now it's time to try it out and hope it works. Strip the insulation off the ends of the tops of the red and black wires. Touch the red wire to the positive end of the battery and the black wire to the other end. Your lights should come on. If not, check your connections to make sure they are good and check the polarity of the LEDs again.
Success
Whew! I can't tell you how happy I was when I finally got my circuit to work. As I mentioned, I'd never wired a circuit before, so it took about 5 attempts before I got it right. I'm hoping this Instructable will help you avoid that frustration.
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