hpr3123 :: Arduino controlled Christmas lights - Free Audiobook

Summary: Controlling Christmas LED lights with an Arduino

Series: Arduino and related devices

Source: [http://hackerpublicradio.org/eps.php?id=3123](http://hackerpublicradio.org/eps.php?id=3123)

1. Inspired by an Instructable project

[https://www.instructables.com/id/LED-VU-Meter-With-Arduino-UNO](https://www.instructables.com/id/LED-VU-Meter-With-Arduino-UNO)

2. Started the project with Arduino Uno.

• Found that power it with the barrel plug made audio input stable

• Tested this theory by using USB power

• Suspect this was due to grounding not being as good with the USB

• This caused LED's to light even without an audio input

• Ended up using an generic Arduino Nano to control the project

3. Modified an audio mic preamplifier from Amazon to condition the output from the laptop music source

4. Ran the output from this to A0 on the Arduino

5. Split the signal out to an external speaker

6. Used digital outputs listed in the sketch to power the LED indicators

• For reference, a sketch is the program that the Arduino runs through a loop.

7. Used pins 10 to 12 as AnalogWrite pin to provide the power to the solid state relays.

8. Used a dremel to separate the power to the hot side of the two power outlets

• Used three of the outlets to power three strings of Christmas tree LED lights.

• Used the other outlet to power the Arduino

9. Bonus

• Using these particular solid state relays, there is still a 10Vac output in off state. It actually worked for good, as the lights are at a nice brightness without a music input.

• Kindly leave a note in the comments if this is common to Solid State relays.

Links:

GY-MAX4466 Electret Microphone Amplifier

[https://www.amazon.com/gp/product/B07C3HXPJ9/ref=ppx\_yo\_dt\_b\_search\_asin\_title?ie=UTF8&psc=1](https://www.amazon.com/gp/product/B07C3HXPJ9/ref=ppx\_yo\_dt\_b\_search\_asin\_title?ie=UTF8&psc=1)

Solid State relay on Ebay

[https://www.ebay.com/itm/25A-40A-SSR-25DA-SSR-40DA-250V-Solid-State-Relay-Module-Alloy-Heat-Sink/401478280169?hash=item5d79f863e9:g:dkwAAOSwiqFaX3f8](https://www.ebay.com/itm/25A-40A-SSR-25DA-SSR-40DA-250V-Solid-State-Relay-Module-Alloy-Heat-Sink/401478280169?hash=item5d79f863e9:g:dkwAAOSwiqFaX3f8)

ELEGOO for Arduino Nano V3.0

[https://www.amazon.com/gp/product/B0713XK923/ref=ppx\_yo\_dt\_b\_search\_asin\_title?ie=UTF8&psc=1](https://www.amazon.com/gp/product/B0713XK923/ref=ppx\_yo\_dt\_b\_search\_asin\_title?ie=UTF8&psc=1)

AnalogWrite

[https://www.arduino.cc/en/pmwiki.php?n=Reference/AnalogWrite](https://www.arduino.cc/en/pmwiki.php?n=Reference/AnalogWrite)

[https://www.arduino.cc/en/Tutorial/AnalogInOutSerial](https://www.arduino.cc/en/Tutorial/AnalogInOutSerial)

My video

Sound Reactive Christmas lights on Archive.org

Edit:

Here is the song I meant to add, to see if it matches my video of the lights.

It is the Trans Siberian Orchestra, Carol of the Bells.

[https://m.youtube.com/watch?v=sCabI3MdV9g](https://m.youtube.com/watch?v=sCabI3MdV9g)