"ON AIR" work-from-home meeting light
Working from home during the pandemic (and after) means a lot of meetings, some of them at odd hours. This had been especially true while working in private equity, with daily 5 AM meetings and regular work until past 9 PM. Visiting friends and family had no way of knowing if they could knock on the door or enter my office.
This is not a problem unique to me. House guests, children, and significant others everywhere face the uncertainty of not knowing if they are interrupting a meeting. But this issue is not a new one, and neither is the solution. Radio and Hollywood have used "ON AIR" signs for decades to indicate the need for silence, so I concocted a plan to emulate their solution: an automated "On Air" sign just above the door to my office that glows when I am in a meeting.
Finding a sign was easy, although for some reason most designs were battery-powered with a manual button to turn them on and off. I refuse to buy any equipment that is reliant on batteries and therefore requires regular maintenance to replace them, but I was able to find one model that also supported USB power. However, instead of automatically turning on when receiving power, a microcontroller in the sign required the user to press a button to activate the light. This is completely unacceptable to me, since it means the light cannot be automated as-is, and therefore requires some hardware hacking.
Time to bring out my handy dandy iFixit kit! Disassembling the light was difficult without damaging the plastic frame, but I eventually managed to unlatch some of the heavy clips holding it together.
The button was simple, just closing a circuit between two wires, so by splicing the two lead wires together, I achieved the same effect as holding the button down continuously (which would also turn on the light).
Now that the lighting element is working, I just need to automate it. In this case, connecting to a smart plug allows me to turn it on and off remotely, and all that is necessary is finding a method of detecting if I am in a meeting. I had a spare open/close button from my IKEA blinds, and this was a great way to put them to use. The buttons use Zigbee to communicate, and so by connecting it to my HomeAssistant Zigbee radio directly, I am able to detect button presses. I simply labeled one side of the up/down button "Meeting" and the other "Over" and used those button presses to remotely trigger the smart plug (and thus the "on air" light) on and off.
This is a great manual solution, but what if I forget to turn it on and off when I start or finish meetings? Like everything else in my smart home, shouldn't it anticipate my needs and just "know" that I am in a meeting? I had originally hoped to pull meeting status from Zoom, but the plethora of different meeting apps (Zoom, Teams, Hangouts, Webex, phone calls, and proprietary meeting apps) make this technically challenging and extremely complicated. Instead, my long-term solution is to pull meeting data from my calendar. If the meeting has attendees other than myself, I will trigger the light automatically at the beginning and end of the calendar event.
Now I no longer have to worry about embarrassing interruptions during meetings and have a new functional and whimsical decoration in my home.