Introduction: DIY Christmas Light Show

About: I love all things programming from making a Led blink on a arduino, to controlling a whole Christmas light show from my phone with raspberry pi and other hardware. If you'd like to see the light show, check ou…

You have probably seen Christmas lights before. You plug them in and they turn on right? BORINING!!! Have you ever wanted to build a Christmas light show? If you don't know what these are, well, the way they work are you drive to a persons house with these lights shows. They have lights that can turn on and off making patterns. More advanced light can turn each led on and off with any color to make very neat patterns. Lots of people also have music that go with there lights. Well in this project, I'm going to show you how to make a small but cool Christmas light show. Now, I do have a video of how mine turned out. It was actually pretty cool. It did have music with it. Now this project cost around ~$50. Now if your reading this when it was published it's not Christmas time! But you can still build it. The video of the lights is above or here if the video doesnt work.



Arduino Uno, Nano, or mega (If you want more then 14 stands of lights, use a Mega, or multiple Mega)

8 channel relay (if you have more than 8 strands of lights, get a 16 channel relay or multiple relays)

small, cut able extension cords. (1 per strand of lights)

~50 feet of wire(Figure 6 feet per strand of lights)

some tools from your toolbox

Step 1: Plan Your Show

How many stands of lights do you want? Do you want to connect multiple together? How far away from your Arduino will the lights be? Do you want music? These plans should be made to see how much stuff you need to buy. You can connect stands of lights together, but they will all have to be on or off together. So for every strand of lights you want to control, that will be 1 Arduino pin, and 1 relay channel. Also one extension cord you will need to cut. Figure $6 - $10 dollars per stand you want to control. The Arduino uno can control 14 stands of lights. The Arduino mega can control 54 strands. If you want even more strands of lights, you could use tx and rx pins on the mega uno.

Step 2: Cut the Extension Cords


It's recommended to use 3 wire extension cords that include a GND wire. So I have a 6, 1 foot extension cords I will share here so I didn't waste good long extension cords. I cut a line from 1 end to the other and cut the white wire (common wire) in the middle. Then I took these orange connectors from home depot, and stuck the wire in it, and then 3 feet of extension wire to the other side. I did this for the other wire too. See picture above. You can use the black wire, but DO NOT use the green wire. If you do not live in the US, the colors will be different. You will have to repeat this step for every strand of lights you want to control. Put the 2 wires in the nc and center plugin of a relay.

Step 3: Plug in Relay and Code!

To plug the relay in, plug 5V into 5V, GND to GND, and the other pins to any digital pin on the Arduino. Then to code the relay, all you have to do is use the code digitalWrite(pin, HIGH); and digitalWrite(pin, LOW); My code is super long because I had the music go to a 3 1/2 minute long song. You could also use s4a to code, but that only works with arduino uno. You could use a program called mblock and add arduino, but I don't know if that works with arduino mega. Once your done coding, just upload and watch your lights! You could also add a real time clock chip to arduino to start the lights at a certain time. It is recommended to put your electronics in your box, so it doesn't short out.

Step 4: Adding Music

In my show, I added music to make the lights go with the music. If you just want to make show for you and not share it with the public, then you might want to use mblock coding because it is easier. Just play your code and here the music from your computer. But if you want to share your show with the public, you should probably do something else. There is ways to hook a sd card to a arduino and a speaker and play your music with that. Or you can hook a sd card to your arduino and the a audio cord to a FM transmitter (see picture above). What is a FM transmitter? It's basically the things radio companies use to send the music to your car. You could buy a smaller one and be able to send your music strait to the people in a car! Now there are many rules to doing this. You have to buy a low power transmitter. That means the signal will only go about a 1/4 of a mile. You can only broadcast on a non used FM station in your area. If you break some of these rules, you could get in trouble. I recommend just using speakers in your front yard.

Step 5: Finish...

I hope you got some lights working and doing what you want them to do. If you have any questions, don't be afraid to ask. I do not go on Instructables much, but I will answer your question as soon as I see it. Hope you enjoyed this project. If you do not see the video of my show, I hope to have it on here soon. Also, I'm not sure if youtube is going to mute the music because it may be copyright.

Oh, one more thing. I am entering this in the Arduino contest that ends 6/22/20. I hope to win so I can get a amazon gift card. If I do win, I'm going to use the money to buy more light equipment so I can have a bigger show to share with you. The show will include lights called RGB pixels (see picture above). I will go over these in a future instructable. If you don't mind, I hope you will vote for me. Thank you so much!

Arduino Contest 2020

Participated in the
Arduino Contest 2020