On Air Sign

Controlled by Zoom, Microsoft Teams, & Alexa

With all the virtual work meetings I do at home now, I needed a way to let the family know to put on some pants before walking into the room. I built this sign out of Walnut, Curly Maple, and RGB LEDs that will automatically turn on when I join a virtual meeting. I can also control it via Amazon Alexa.

I made the case out of Walnut. I cut the sign front out of Curly Maple on my CNC. I then placed white acrylic behind it to defuse the RGB LEDs

I control the RGB LEDs via an ESP32 and three N-Channel MOSFETs. The ESP32 is running code to emulate a Philips Hue Bridge with an Extended Color Light. This allows Amazon Echo to discover and control the sign as if it was a Philips Extended Color Light with full support for colors and brightness. It also supports color temperature, but instead of having the sign show different shades of white, I chose to have the color temperature implement animation patterns. For example 'warm white' will cause the On Air Sign to play a rainbow pattern by cycling through all the colors.

What really makes this project awesome is how it automatically turns on when I join a virtual meeting. This magic happens because of the companion software I wrote in C# that runs on my PC to detect a Zoom, WebEx, Discord, and MicrosoftTeams Meeting by monitoring UDP traffic. This application automatically turns on the sign when I join a virtual meeting and turns the sign off when I leave the meeting.

This sign provides a nice visual clue to my family that I am in a meeting WITH MY VIDEO CAMERA ON, so don't embarrass yourself.

Below are all the videos that I have created to explain each part of this project in greater detail. Here is a playlist of all the videos: My On Air Sign Project Playlist

In this video, I walk through the windows application I wrote to detech Zoom, WebEx, and Microsoft Teams meetings and automatically turn on the sign.

Coding Alexa Support for ESP32 (Arduino)

In this video, I walk through the woodworking that it took to build the case out of walnut and maple.

Alexa Voice Control for ESP32 (Arduino) by Emulating Philips Hue Light

How to Build an RGB LED On Air Sign Controlled by Alexa out of Walnut/Curly Maple

Parts List for the Electronics

ESP32 Microcontroller

N-Channel Power Mosfet TO-220

RGB 5050 LED strip


Circuit Diagram

Source Code

Source code for this project can be found on my git hub

Here is the Arduino code that runs on the ESP32

Here is the desktop application that detect when I am in a Zoom, WebEx or Microsoft Teams meeting and automatically turn on or off the my sign.

Reference Info

RGB LD Strips info on Adafruit - link

LED Strip SMD 5050 info on Arduino forum - link

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